Merge pull request #1740 from ludovic111/refactor/port-pack-legacy-structure-mods

🤖 Agent: merged after verify passed and the integration run on the desktop.
refactor(port-pack): move YUNG, Lithostitched and CTOV conversion into legacy_structure_mods
2026-11-07 17:21:49 -10:00 · 2026-10-25 05:41:33 +01:00 · 2026-10-25 05:35:36 +01:00 · 2026-10-25 05:07:12 +01:00 · 2026-10-25 03:45:53 +01:00 · 2026-10-25 03:30:13 +01:00
688 changed files with 18955 additions and 27658 deletions
@@ -3,3 +3,4 @@
 docs/launcher-commands.md text eol=lf
 docs/horizon-ctl-commands.md text eol=lf
 website/src/tokens.css text eol=lf
+docs/api/*-reference.md text eol=lf
@@ -61,7 +61,8 @@ jobs:
        if: steps.rust.outputs.required != 'false'
        run: |
          cargo +stable fmt --all -- --check
-          cargo +stable clippy --workspace --all-targets -- -D warnings
+          # With the game's code mods (on in every release build, off by default).
+          cargo +stable clippy --workspace --all-targets --features horizon-client/mods -- -D warnings
          # The server build (released as horizon-engine): the game without sound or controllers.
          cargo +stable clippy -p horizon-client --all-targets --no-default-features -- -D warnings
      # Libraries, binaries and integration tests, then doc tests: not the ~275 examples, which clippy above already
@@ -69,8 +70,8 @@ jobs:
      - name: Test Rust core and voxel kernel correctness
        if: steps.rust.outputs.required != 'false'
        run: |
-          cargo +stable test --workspace --lib --bins --tests
-          cargo +stable test --workspace --doc
+          cargo +stable test --workspace --lib --bins --tests --features horizon-client/mods,horizon-mods/pack
+          cargo +stable test --workspace --doc --features horizon-client/mods,horizon-mods/pack
  parity:
    if: github.event_name == 'pull_request' && github.event.pull_request.head.repo.full_name == github.repository
    uses: ./.github/workflows/parity.yml
@@ -429,7 +430,7 @@ jobs:
        env:
          RUSTUP_TOOLCHAIN: stable
        run: python tools/test_float_log_parity.py
-  portable-mod:
+  jfr-analysis:
    if: github.event_name == 'workflow_dispatch'
    runs-on: [self-hosted, linux, horizon-game]
    steps:
@@ -441,101 +442,7 @@ jobs:
        with:
          distribution: temurin
          java-version: '25'
-      - name: Compile original mod and test metrics
-        run: python tools/build_mod.py
      - name: Verify streaming JFR analysis against the JDK exporter
        run: python tools/test_jfr.py
      - name: Verify ZGC pause and allocation event interpretation
        run: python tools/test_jfr.py --gc zgc
-      - name: Build pinned portable packs
-        run: python tools/build_pack.py
-      - name: Measure isolated worker pacing on this platform
-        run: python -c "from tools.build_mod import benchmark_workers; benchmark_workers()"
-      - name: Measure isolated debounce queue polling
-        run: python -c "from tools.build_mod import benchmark_debounce; benchmark_debounce()"
-      - name: Measure wakeable idle queue latency
-        run: python -c "from tools.build_mod import benchmark_idle; benchmark_idle()"
-      - name: Measure object allocations with compact headers off and on
-        run: python -c "from tools.build_mod import benchmark_headers; benchmark_headers()"
-      - name: Test pack integrity and comparisons
-        run: python -m unittest discover -s tests -v
-      - name: Start recommended OpenGL macOS clients and verify framebuffer readback
-        if: runner.os == 'macOS'
-        run: |
-          python tools/test_client_graphics.py --native-display
-          cp dist/client-graphics-smoke.json dist/client-graphics-macos-title.json
-          python tools/test_client_graphics.py --native-display --world
-          cp dist/client-graphics-smoke.json dist/client-graphics-macos-world.json
-      - name: Compile the private dispatch fixture
-        run: python -c "from tools.build_mod import build_dispatch_fixture; build_dispatch_fixture()"
-      - name: Compile the private integrated-server graphics fixture
-        run: python -c "from tools.build_mod import build_integration_fixture; build_integration_fixture('server-graphics', 'dev.horizonlab.metrics.ServerGraphicsIntegration', fixture_dependencies={})"
-      - name: Compile the private tick-manager state fixture
-        run: python -c "from tools.build_mod import build_integration_fixture; build_integration_fixture('tick-state', 'dev.horizonlab.metrics.TickStateIntegration')"
-      - name: Compile the private terrain tick membership fixture
-        run: python -c "from tools.build_mod import build_tick_dedup_fixture; build_tick_dedup_fixture()"
-      - name: Compile the private culling whitelist fixture
-        run: python -c "from tools.build_mod import build_culling_empty_fixture; build_culling_empty_fixture()"
-      - name: Compile the private culling ray geometry fixture
-        run: python -c "from tools.build_mod import build_integration_fixture; build_integration_fixture('culling-rays', 'dev.horizonlab.dispatch.CullingRayIntegration', ['entityculling'], ['CullingRayAccess'])"
-      - name: Compile the private terrain position lookup fixture
-        run: python -c "from tools.build_mod import build_integration_fixture; build_integration_fixture('terrain-position', 'dev.horizonlab.dispatch.PositionIntegration')"
-      - name: Compile the private terrain quad reuse fixture
-        run: python -c "from tools.build_mod import build_integration_fixture; build_integration_fixture('quad-reuse', 'dev.horizonlab.dispatch.QuadReuseIntegration')"
-      - name: Compile the private object-size agent and terrain quad fixture
-        run: python -c "from tools.test_quad_sizes import build_agent; from tools.build_mod import build_integration_fixture; build_agent(); build_integration_fixture('quad-size', 'dev.horizonlab.dispatch.QuadSizeIntegration')"
-      - name: Compile the private terrain read shutdown fixture
-        run: python -c "from tools.build_mod import build_integration_fixture; build_integration_fixture('terrain-read', 'dev.horizonlab.dispatch.TerrainReadIntegration')"
-      - name: Install headless graphics libraries for applied-hook checks
-        if: runner.os == 'Linux'
-        run: sudo apt-get update && sudo apt-get install -y xvfb libgl1 libegl1 libvulkan1 mesa-vulkan-drivers libasound2t64 libxkbcommon0
-      - name: Verify integrated-server graphics report against the actual device
-        run: python tools/test_server_graphics.py ${{ runner.os == 'macOS' && '--native-display' || '' }}
-      - name: Exercise the applied dispatcher hooks and upstream rejection path
-        if: runner.os == 'Linux'
-        run: python tools/test_dispatch.py
-      - name: Verify applied tick membership transitions and allocation
-        if: runner.os == 'Linux'
-        run: python tools/test_tick_dedup.py
-      - name: Verify live culling whitelist registration and empty iteration
-        if: runner.os == 'Linux'
-        run: python tools/test_culling_empty.py
-      - name: Compare applied culling ray geometry and provider queries
-        if: runner.os == 'Linux'
-        run: python tools/test_culling_rays.py
-      - name: Verify actual full-data position lookup equivalence
-        if: runner.os == 'Linux'
-        run: python tools/test_terrain_position.py
-      - name: Verify actual terrain quad geometry and allocation
-        if: runner.os == 'Linux'
-        run: python tools/test_quad_reuse.py
-      - name: Measure actual builder and quad shallow sizes in both header modes
-        if: runner.os == 'Linux'
-        run: python tools/test_quad_sizes.py
-      - name: Verify interrupted DH reads and preserved shared futures
-        if: runner.os == 'Linux'
-        run: python tools/test_terrain_read.py
-      - name: Upload original mod and pack manifests only
-        uses: actions/upload-artifact@v4
-        with:
-          name: horizon-linux
-          path: |
-            dist/*.mrpack
-            dist/horizon-*.jar
-            dist/worker-pacing-benchmark.txt
-            dist/debounce-queue-benchmark.txt
-            dist/idle-queue-benchmark.txt
-            dist/object-header-benchmark.txt
-            dist/dispatch-integration.json
-            dist/tick-dedup-integration.json
-            dist/culling-empty-integration.json
-            dist/terrain-read-integration.json
-            dist/culling-rays-integration.json
-            dist/terrain-position-integration.json
-            dist/quad-reuse-integration.json
-            dist/quad-size-integration.json
-            dist/server-graphics-smoke.json
-            dist/client-graphics-smoke.json
-            dist/client-graphics-macos-title.json
-            dist/client-graphics-macos-world.json
-          retention-days: 3
@@ -1,8 +1,8 @@
 name: release
 # Automatic game releases (docs/release-flow.md). After every green `checks` run on main, every 10 minutes (so a
 # release waiting for merges to settle goes out without another merge) and by hand, tools/release_train.py decides:
-# a release when pull requests merged since the last one changed what players run and the newest merged 5 minutes
-# ago (the oldest 20 minutes ago, if merges never pause), or at once for a pull request labelled release-now.
+# a release when 5 pull requests merged since the last one changed what players run and the newest merged 5 minutes
+# ago, or when the oldest has waited 6 hours, or at once for a pull request labelled release-now.
 # RELEASES_PAUSED=1 (repository variable) stops them; so does an open issue labelled release-blocker, forced runs too.
 # Builds Linux (an older Ubuntu, so the binary runs on any recent distribution and on NixOS through nix-ld) and
 # Windows on GitHub, macOS on the Mac mini's runner (MAC_RUNNER=macos-latest sends it to GitHub), then
@@ -133,7 +133,8 @@ jobs:
        if: runner.os == 'Linux'
        run: sudo apt-get update && sudo apt-get install -y --no-install-recommends libasound2-dev libudev-dev
      - name: Build the client, horizon-ctl, horizon-prepare and horizon-server
-        run: cargo build --release --locked -p horizon-client --bin horizon-client --bin horizon-ctl -p horizon-prepare --bin horizon-prepare -p horizon-server --bin horizon-server
+        # `horizon-client/mods`: every released game runs code mods (the feature is off in dev builds).
+        run: cargo build --release --locked --features horizon-client/mods -p horizon-client --bin horizon-client --bin horizon-ctl -p horizon-prepare --bin horizon-prepare -p horizon-server --bin horizon-server
      - name: Every program the release folder takes was built
        run: |
          for binary in horizon-client horizon-ctl horizon-prepare horizon-server; do
@@ -255,8 +256,9 @@ jobs:
        run: |
          set -euo pipefail
          # After the client is packaged: target/release/horizon-client is rebuilt without the audio and
-          # controllers features, so it needs neither libasound nor libudev (minimal server images lack them).
-          cargo build --release --locked -p horizon-client --no-default-features --bin horizon-client
+          # controllers features, so it needs neither libasound nor libudev (minimal server images lack them),
+          # and with code mods like the client.
+          cargo build --release --locked -p horizon-client --no-default-features --features mods --bin horizon-client
          cargo run --locked -p xtask -- package-server target/release/horizon-client "dist/${{ matrix.server_dir }}"
          folder="dist/${{ matrix.server_dir }}"
          python3 tools/check_imports.py --server "$folder/horizon-engine" "$folder/horizon-server" "$folder/horizon-prepare"
@@ -365,10 +367,15 @@ jobs:
          TAG: ${{ needs.decide.outputs.tag }}
        run: |
          signature=(); [[ -f dist/SHA256SUMS.sig ]] && signature=(dist/SHA256SUMS.sig)
-          # The release and the latest at once: there is one channel (docs/release-flow.md).
+          # The release and the latest at once: there is one channel (docs/release-flow.md). Each archive gets a
+          # label (file#label), which GitHub's page shows instead of the file name, so nobody takes the game's
+          # files for the download (#1647). Launchers, servers and install.sh match the name, which stays.
          gh release create "$TAG" --target "${{ needs.decide.outputs.head }}" --title "$(cat notes/title.txt)" \
-            --notes-file notes/body.md --latest dist/horizon-linux-x86_64.tar.gz \
-            dist/horizon-windows-x64.zip dist/horizon-macos-arm64.zip dist/horizon-server-linux-x86_64.tar.gz \
+            --notes-file notes/body.md --latest \
+            "dist/horizon-linux-x86_64.tar.gz#Game files the launcher installs: Linux (horizon-linux-x86_64.tar.gz)" \
+            "dist/horizon-windows-x64.zip#Game files the launcher installs: Windows (horizon-windows-x64.zip)" \
+            "dist/horizon-macos-arm64.zip#Game files the launcher installs: macOS (horizon-macos-arm64.zip)" \
+            "dist/horizon-server-linux-x86_64.tar.gz#Dedicated server for Linux (horizon-server-linux-x86_64.tar.gz)" \
            dist/SHA256SUMS "${signature[@]}" dist/smoke-test.json
      - name: Dry run, the release that would be published
        if: needs.decide.outputs.dry_run == 'true'
@@ -12,17 +12,20 @@ Feature → files → harness for the most-changed areas: [docs/architecture.md]
  folders in `HORIZON_HOME` (the game's data), `HORIZON_LAUNCHER_HOME`, `XDG_DATA_HOME` and
  `XDG_CONFIG_HOME`, plus `HORIZON_LAUNCHER_NO_SELF_UPDATE=1` and `HORIZON_NO_AUDIO=1`. Never write to
  `~/.local/share/{applications,horizon,horizon-launcher}` or `~/.local/bin`.
- **Mark what an agent posts.** A PR body starts with
-  `> 🤖 Opened by Ludovic's AI agent (Claude), not by Ludovic himself.` (issues: "Filed by", reviews:
-  "Review by"); every comment starts with `🤖 Agent:`. Never write as Ludovic.
- **Attribution.** Commits end with `Co-Authored-By: Claude <model> <[email protected]>`; PR bodies end
-  with `🤖 Generated with [Claude Code](https://claude.com/claude-code)`.
+- **Mark what an agent posts.** A PR body starts with a line naming whose agent opened it and with what.
+  Ludovic's agents write `> 🤖 Opened by Ludovic's AI agent (Claude), not by Ludovic himself.`, and a
+  contributor's agent names its own person and tool (issues: "Filed by", reviews: "Review by"). Every
+  comment starts with `🤖 Agent:`. Never write as Ludovic or as anyone else.
+- **Attribution.** Commits end with a `Co-Authored-By:` line for the agent that wrote them, and PR bodies
+  with that agent's own "Generated with" line. Ludovic's agents use
+  `Co-Authored-By: Claude <model> <[email protected]>` and
+  `🤖 Generated with [Claude Code](https://claude.com/claude-code)`.
 - Everything players run is Rust. Python/Java only for dev tools and harness drivers in `tools/`.
 - Horizon-only features follow [docs/design-system.md](docs/design-system.md) and are off by default where
  they would change the vanilla look.
 - Small PRs (< ~500 lines). Labels: `feature` (players get something new), `skip-release` (they see no
-  change), none for a fix. Agents never add `release-now`: the maintainer decides it. Every merge to main ships
-  ([docs/release-flow.md](docs/release-flow.md)).
+  change), none for a fix. Agents never add `release-now`: the maintainer decides it. Merges ship in batches of 5, or after
+  6 hours ([docs/release-flow.md](docs/release-flow.md)).
 - Contributors first: `gh pr list --state open --search <area>` before you start; never duplicate theirs.

 ## Crates
@@ -40,12 +43,12 @@ Game workspace (root `Cargo.toml`); `launcher/` and `crates/horizon-telemetry-se
 | `horizon-server` | `horizon-server`: `server.toml`, CLI, supervisor of the headless game ([docs/hosting.md](docs/hosting.md)) |
 | `horizon-server-files` | `server.properties`, eula, ops/whitelist/bans, usercache |
 | `horizon-friends`, `horizon-relay` | Play with Friends: invite codes, encrypted tunnel, the relay ([docs/play-with-friends.md](docs/play-with-friends.md)) |
-| `horizon-shaderpack` | OptiFine/Iris packs: preprocessor, GLSL → WGSL ([docs/shader-packs.md](docs/shader-packs.md)) |
 | `horizon-mods`, `horizon-mod-sdk`, `cargo-horizon-mod` | Sandboxed WebAssembly mods: runtime, SDK + WIT, `cargo horizon-mod` ([docs/mods.md](docs/mods.md)) |
 | `horizon-port-pack` | Porting Java modpacks ([docs/modpacks.md](docs/modpacks.md)) |
+| `horizon-shaders` | Shader packs (the `shaders/` folder format), rebuilt clean-room from a written spec of the format; no wgpu |
 | `horizon-theme` | Design tokens and fonts for the launcher, the game's own menus and the website |
 | `horizon-telemetry`, `horizon-telemetry-server`, `horizon-bench` | Opt-in data collection, its ingest server, the benchmark report format |
-| `horizon-dualsense`, `horizon-threads`, `horizon-release-sign`, `horizon-bots`, `voxel-kernels`, `xtask` | DualSense output, thread priorities, signed release checksums, load-test bots, occupancy kernels, repo tasks |
+| `horizon-dualsense`, `horizon-threads`, `horizon-release-sign`, `horizon-bots`, `xtask` | DualSense output, thread priorities, signed release checksums, load-test bots, repo tasks |
 | `launcher/` | GPUI launcher: `main.rs` (UI), `backend.rs` (installs, updates), `cli.rs`, `mcp.rs`, `*_page.rs` |

 Other top-level folders: `tools/` (harnesses and dev scripts), `tests/` (Python unit tests: `python3 -m
@@ -123,7 +126,6 @@ python3 tools/agent_control_e2e.py         # horizon-ctl / MCP end to end
 | Input | game.rs `fn window_event`, `fn key_pressed`, `fn play_mouse`; L: `keybinds.rs`, `keymapping.rs`, `key_names.rs`, `mouse.rs`, `input.rs`, `interaction_input.rs`, `gamepad.rs`, `osk.rs`, `clipboard.rs`; G: `pad.rs`, `pad_menu.rs` |
 | Audio | L: `audio.rs` (mixer), `sound_engine.rs`, `sound_events.rs`, `music.rs`, `ambience.rs`; G: `music.rs`, `subtitle_hud.rs` |
 | Resource packs | L: `packs.rs` + `packs/`, `pack_screen.rs`, `atlas_sources.rs`, `sprites.rs`, `mipmap.rs`, `model_library.rs`, `font.rs`, `lang.rs`; crate `horizon-assets`; G: `packs.rs` |
-| Shader packs | L: `shader_pack.rs` (Horizon WGSL packs), `java_pack.rs` + crate `horizon-shaderpack` (Iris/OptiFine), `gfx/pack_stages.rs`, `gfx/java_stages.rs`; G: `shader_packs.rs` |
 | Agent control | L: `control.rs` (socket), `bin/horizon-ctl/`; G: `control.rs`, `agent.rs`, `events.rs`, `ui_control.rs` ([docs/agent-control.md](docs/agent-control.md)) |
 | Mods | crate `horizon-mods`; G: `mods.rs`; L: `mod_content.rs`, `mod_list.rs` |
 | Horizon extras, settings | L: `extras.rs`, `graphics.rs`, `settings.rs`, `minimap.rs`; G: `extras.rs`, `tweaks.rs`, `options.rs` |
@@ -148,19 +150,19 @@ python3 tools/agent_control_e2e.py         # horizon-ctl / MCP end to end

 ## The two single-player paths

-1. **In-frame (default since #1428):** the window's `Game` ticks the world itself, one level that follows
-   the player (`fn enter_dimension`). This is what Stable players run and what harnesses test.
-2. **Server thread (`--server-thread` or `HORIZON_SERVER_THREAD=1`):** `game/integrated.rs` runs a second
-   `Game` (`serving`) on a "Server thread" with one level per dimension; the window joins it as a client
-   through memory (`remote`), exactly as a LAN guest or a dedicated server's player does. Not at parity yet:
-   open `[server-thread]` issues list the gaps.
+1. **Server thread (default since #1514):** `game/integrated.rs` runs a second `Game` (`serving`) on a
+   "Server thread" with one level per dimension; the window joins it as a client through memory (`remote`),
+   exactly as a LAN guest or a dedicated server's player does. This is what players run. Open
+   `[server-thread]` issues list the gaps left.
+2. **In-frame (`--in-frame`, `--no-server-thread` or `HORIZON_SERVER_THREAD=0`):** the window's `Game` ticks
+   the world itself, one level that follows the player (`fn enter_dimension`). Most harnesses test this path.

 LAN guests and dedicated servers always use the server code, so a fix there serves both. Test both paths
 when you touch player-facing gameplay:

 ```sh
-cargo run --profile fast -p horizon-client -- --resources .local/horizon-client/26.3 --world T                   # in-frame
-cargo run --profile fast -p horizon-client -- --resources .local/horizon-client/26.3 --world T --server-thread   # server thread
+cargo run --profile fast -p horizon-client -- --resources .local/horizon-client/26.3 --world T               # server thread
+cargo run --profile fast -p horizon-client -- --resources .local/horizon-client/26.3 --world T --in-frame    # in-frame
 python3 tools/lan_e2e.py --check <name>                  # host in-frame, guest is a server client
 python3 tools/lan_e2e.py --server-thread --check <name>  # host on its server thread (portals, levels, distance, lava need it)
 python3 tools/parity.py dedicated_server server_entities server_player_damage
@@ -40,6 +40,15 @@ probe against Horizon, and compares their outputs. There are about 290 of them.
 Never commit game files, decompiled source or prepared resources (`.local/`): `tools/check_public_tree.py` rejects
 them (`git config core.hooksPath .githooks` runs it before every commit).

+## Only original code
+
+Horizon's code is written from Minecraft 26.3 itself and from public documentation, never from another mod, loader
+or renderer. Don't read, copy, translate or paraphrase the source of Iris, OptiFine, Sodium or any other project,
+and don't send code an AI tool wrote from it. Their user documentation and file formats are fine to read, and their
+packs and mods are fine to run and observe. Shader packs were removed on 24 October 2026 (#1561) because their code
+had been written from another project's source; they come back only as a clean-room rewrite from a written
+description of the pack format.
+
 ## Before asking for review

 Run the self-check and paste the block it prints into your pull request:
@@ -155,7 +155,7 @@ dependencies = [
 "objc2-foundation 0.3.2",
 "parking_lot",
 "percent-encoding",
- "windows-sys 0.59.0",
+ "windows-sys 0.60.2",
 "wl-clipboard-rs",
 "x11rb",
 ]
@@ -178,15 +178,6 @@ version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "175571dd1d178ced59193a6fc02dde1b972eb0bc56c892cde9beeceac5bf0f6b"

-[[package]]
-name = "ascii-canvas"
-version = "4.0.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ef1e3e699d84ab1b0911a1010c5c106aa34ae89aeac103be5ce0c3859db1e891"
-dependencies = [
- "term",
-]
-
 [[package]]
 name = "ash"
 version = "0.38.0+1.3.281"
@@ -214,30 +205,15 @@ version = "0.22.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "72b3254f16251a8381aa12e40e3c4d2f0199f8c6508fbecb9d91f575e0fbb8c6"

-[[package]]
-name = "bit-set"
-version = "0.8.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "08807e080ed7f9d5433fa9b275196cfc35414f66a0c79d864dc51a0d825231a3"
-dependencies = [
- "bit-vec 0.8.0",
-]
-
 [[package]]
 name = "bit-set"
 version = "0.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "09ec2f926cc3060f09db9ebc5b52823d85268d24bb917e472c0c4bea35780a7d"
 dependencies = [
- "bit-vec 0.9.1",
+ "bit-vec",
 ]

-[[package]]
-name = "bit-vec"
-version = "0.8.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5e764a1d40d510daf35e07be9eb06e75770908c27d411ee6c92109c9840eaaf7"
-
 [[package]]
 name = "bit-vec"
 version = "0.9.1"
@@ -283,16 +259,6 @@ dependencies = [
 "objc2 0.6.5",
 ]

-[[package]]
-name = "borsh"
-version = "1.8.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "553c5d846a6ba5150c65e3b1b8ec073bcf1abc20f9b7220de384a4443ea4e20a"
-dependencies = [
- "bytes",
- "cfg_aliases",
-]
-
 [[package]]
 name = "bumpalo"
 version = "3.20.3"
@@ -484,15 +450,6 @@ dependencies = [
 "crossbeam-utils",
 ]

-[[package]]
-name = "convert_case"
-version = "0.10.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "633458d4ef8c78b72454de2d54fd6ab2e60f9e02be22f3c6104cdc8a4e0fceb9"
-dependencies = [
- "unicode-segmentation",
-]
-
 [[package]]
 name = "coords-hud"
 version = "0.1.0"
@@ -797,41 +754,6 @@ dependencies = [
 "syn 2.0.119",
 ]

-[[package]]
-name = "darling"
-version = "0.20.11"
-source = "registry+https://github.com/rust-lang/crates.io-index"
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@@ -1441,9 +1278,9 @@ dependencies = [
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@@ -1478,7 +1315,7 @@ dependencies = [
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@@ -1493,10 +1330,11 @@ dependencies = [
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 dependencies = [
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@@ -1542,6 +1380,7 @@ dependencies = [
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+ "ipconfig",
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@@ -1596,12 +1435,9 @@ dependencies = [
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+
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 dependencies = [
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@@ -2197,7 +1973,6 @@ dependencies = [
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 [[package]]
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@@ -3483,6 +3167,16 @@ dependencies = [
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+[[package]]
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+dependencies = [
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+ "windows-sys 0.61.2",
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+
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-
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@@ -3687,12 +3341,6 @@ dependencies = [
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-
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@@ -3853,7 +3501,7 @@ checksum = "b8765b90061cba6c22b5831f675da109ae5561588290f9fa2317adab2714d5a6"
 dependencies = [
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- "petgraph 0.8.3",
+ "petgraph",
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 [[package]]
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@@ -4574,8 +4218,8 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
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 dependencies = [
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- "bit-vec 0.9.1",
+ "bit-set",
+ "bit-vec",
 "bitflags 2.13.2",
 "bytemuck",
 "cfg_aliases",
@@ -4625,7 +4269,7 @@ dependencies = [
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 "arrayvec",
 "ash",
- "bit-set 0.10.0",
+ "bit-set",
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 "bytemuck",
@@ -4689,6 +4333,12 @@ dependencies = [
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+[[package]]
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+
 [[package]]
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@@ -4821,6 +4471,17 @@ dependencies = [
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 ]

+[[package]]
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+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "02752bf7fbdcce7f2a27a742f798510f3e5ad88dbe84871e5168e2120c3d5720"
+dependencies = [
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+ "windows-result 0.4.1",
+ "windows-strings",
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+
 [[package]]
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@@ -5123,7 +4784,7 @@ dependencies = [
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 "sctk-adwaita",
 "smithay-client-toolkit",
- "smol_str 0.2.2",
+ "smol_str",
 "tracing",
 "unicode-segmentation",
 "wasm-bindgen",
@@ -1,6 +1,6 @@
 [workspace]
 exclude = ["launcher", "crates/horizon-telemetry-server", "third_party/wgpu-hal"]
-members = ["crates/horizon-core", "crates/horizon-dualsense", "crates/horizon-threads", "crates/horizon-world", "crates/voxel-kernels", "crates/horizon-client", "crates/horizon-server-files", "crates/horizon-server", "crates/horizon-bots", "crates/horizon-assets", "crates/horizon-protocol", "crates/horizon-theme", "crates/horizon-shaderpack", "crates/horizon-prepare", "crates/horizon-telemetry", "crates/horizon-bench", "crates/horizon-friends", "crates/horizon-relay", "crates/horizon-mod-sdk", "crates/horizon-mods", "crates/horizon-mods/tests/guest", "crates/cargo-horizon-mod", "crates/horizon-port-pack", "crates/horizon-release-sign", "crates/horizon-mod-sdk/examples/coords-hud", "xtask"]
+members = ["crates/horizon-core", "crates/horizon-dualsense", "crates/horizon-threads", "crates/horizon-world", "crates/horizon-client", "crates/horizon-server-files", "crates/horizon-server", "crates/horizon-bots", "crates/horizon-assets", "crates/horizon-protocol", "crates/horizon-theme", "crates/horizon-prepare", "crates/horizon-telemetry", "crates/horizon-bench", "crates/horizon-friends", "crates/horizon-relay", "crates/horizon-mod-sdk", "crates/horizon-mods", "crates/horizon-mods/tests/guest", "crates/cargo-horizon-mod", "crates/horizon-port-pack", "crates/horizon-shaders", "crates/horizon-release-sign", "crates/horizon-mod-sdk/examples/coords-hud", "xtask"]
 resolver = "2"

 [workspace.package]
@@ -45,7 +45,7 @@ The [documentation](https://playhorizon.dev/docs/) covers each of these.

 - **The game:** singleplayer with vanilla's world generation, mobs, villagers, raids, redstone, every command, the HUD and the recipe book, on saves in vanilla's format. Worlds from 1.8 to 26.2 are upgraded as vanilla does. [Status table](#project-status).
 - **Horizon's own extras:** new menus (vanilla's are one setting away), graphics presets, distant terrain up to 1024 chunks, controller support, optional zoom, minimap and more, all off by default where they would change the vanilla look. See [Settings](https://playhorizon.dev/docs/settings).
- **Resource packs, shader packs and data packs:** resource packs work, Java shader packs run their full-screen effects (experimental), and data packs load functions, predicates and item modifiers.
+- **Resource packs and data packs:** resource packs work, and data packs load functions, predicates and item modifiers.
 - **Playing with others:** invite friends from the pause menu's Friends button with a code, Open to LAN, and joining offline-mode servers. Horizon cannot sign in to a Microsoft account yet, so it cannot join servers that check accounts. See [Multiplayer](https://playhorizon.dev/docs/multiplayer).
 - **Mods:** Horizon has its own mod system (Rust compiled to WebAssembly). Java mod jars do not run. See [Mods and data packs](https://playhorizon.dev/docs/mods).

@@ -57,7 +57,7 @@ Screenshots, captured in the Rust client itself with vanilla assets and no mods
  </tr>
  <tr>
    <td width="50%"><img src="docs/media/survival.webp" alt="Survival at dusk: a zombie walks up, with the hotbar, health, hunger and experience"></td>
-    <td width="50%"><img src="docs/media/settings.webp" alt="Vanilla's Video Settings screen with Horizon's own buttons at the top: Horizon Graphics, Advanced Graphics and Shader Packs"></td>
+    <td width="50%"><img src="docs/media/settings.webp" alt="Vanilla's Video Settings screen with Horizon's own buttons at the top: Horizon Graphics and Advanced Graphics"></td>
  </tr>
  <tr>
    <td width="50%"><img src="docs/media/village.webp" alt="A plains village among savanna hills, with farms, villagers and an iron golem"></td>
@@ -1,35 +1,5 @@
 # Third-party notices

-## CullLeaves
-
-The optional leaf and mangrove-root face-culling behavior is adapted from
-[CullLeaves](https://github.com/TeamMidnightDust/CullLeaves) by MidnightDust.
-Its MIT license is reproduced below.
-
-```text
-MIT License
-
-Copyright (c) 2020 MidnightDust
-
-Permission is hereby granted, free of charge, to any person obtaining a copy
-of this software and associated documentation files (the "Software"), to deal
-in the Software without restriction, including without limitation the rights
-to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-copies of the Software, and to permit persons to whom the Software is
-furnished to do so, subject to the following conditions:
-
-The above copyright notice and this permission notice shall be included in all
-copies or substantial portions of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-SOFTWARE.
-```
-
 ## wgpu-hal

 `third_party/wgpu-hal` is [wgpu-hal](https://github.com/gfx-rs/wgpu) 30.0.1 by the gfx-rs
@@ -131,8 +131,8 @@ average) and reached the ThinkPad over the tailnet.
  It ran with Paper's defaults except `connection-throttle: -1` in `bukkit.yml`. Every bot connects from one
  address, and the default throttle (4 s) refused all but the first. Paperclip patched the pinned server jar
  from its cache. Same Java and heap.
- Fabric + Lithium: the pinned server jar on Fabric loader 0.19.5 (`packs/fabric.lock.json`) with Lithium
-  `mc26.3-0.26.2-fabric` (`packs/mods.lock.json`, checked against its SHA-512). Lithium needs no Fabric API.
+- Fabric + Lithium: the pinned server jar on Fabric loader 0.19.5 (`tools/benchmark-deps/fabric.lock.json`) with Lithium
+  `mc26.3-0.26.2-fabric` (`tools/benchmark-deps/mods.lock.json`, checked against its SHA-512). Lithium needs no Fabric API.
  Same Java and heap.

 The Paper and Fabric jars are dev-only downloads into `.local/server-bench/jars` and are never committed or
@@ -1,8 +1,7 @@
 //! The machine a report was measured on. CPU, RAM and OS are detected here; the GPU and the display
 //! come from the program that rendered (the game knows its adapter, the launcher its window).

-use std::process::Command;
-
+use horizon_telemetry::system::command_output as output;
 use serde::{Deserialize, Serialize};

 #[derive(Clone, Debug, Default, PartialEq, Serialize, Deserialize)]
@@ -173,12 +172,6 @@ pub fn cpu_seconds(pid: u32) -> Option<f64> {
    Some(ticks / 100.0)
 }

-fn output(program: &str, args: &[&str]) -> Option<String> {
-    let out = Command::new(program).args(args).output().ok()?;
-    let text = String::from_utf8(out.stdout).ok()?.trim().to_owned();
-    (out.status.success() && !text.is_empty()).then_some(text)
-}
-
 #[cfg(target_os = "macos")]
 fn os_version() -> Option<String> {
    output("sw_vers", &["-productVersion"])
@@ -245,13 +245,19 @@ pub struct Report {
 impl Report {
    /// An empty report for this machine, created now.
    pub fn new(kind: Kind, app: App) -> Report {
+        Self::with_hardware(kind, app, Hardware::detect())
+    }
+
+    /// Starts a report using supplied hardware, without running system probes.
+    /// Interactive apps can collect the remaining machine details after their first frame.
+    pub fn with_hardware(kind: Kind, app: App, hardware: Hardware) -> Report {
        Report {
            format: FORMAT.to_owned(),
            version: VERSION,
            kind,
            created: utc_now(),
            app,
-            hardware: Hardware::detect(),
+            hardware,
            conditions: Conditions::default(),
            metrics: BTreeMap::new(),
            frames: Vec::new(),
@@ -18,7 +18,8 @@ horizon-protocol = { path = "../horizon-protocol" }
 horizon-server-files = { path = "../horizon-server-files" }
 horizon-friends = { path = "../horizon-friends" }
 # Horizon mods: sandboxed WebAssembly components, off unless installed and turned on (docs/mods.md).
-horizon-mods = { path = "../horizon-mods" }
+# Their runtime is the `mods` feature.
+horizon-mods = { path = "../horizon-mods", default-features = false }
 wgpu = { version = "30.0.1", default-features = false, features = ["std", "parking_lot", "vulkan", "metal", "wgsl"] }
 winit = "0.30.13"
 pollster = "0.4"
@@ -26,15 +27,13 @@ bytemuck = { version = "1.24", features = ["derive"] }
 glam = "0.30"
 png = "0.18"
 sha2 = "0.10.9"
+# Server resource packs are checked and cached by their SHA-1, as vanilla does.
+sha1 = "0.10"
 serde = { version = "1", features = ["derive"] }
 serde_json = { version = "1.0.151", features = ["raw_value"] }
-# Shader packs: pack.toml, and WGSL checked before it reaches wgpu.
-toml = "1.1"
 # hlsl-out: the gfx.rs tests translate every shader as wgpu's DirectX 12 backend does. A normal feature,
 # not a dev-dependency's, so builds, tests and examples share one build of naga, wgpu and this crate.
 naga = { version = "30.0.1", features = ["wgsl-in", "hlsl-out"] }
-# Java (OptiFine/Iris) shader packs, translated to WGSL.
-horizon-shaderpack = { path = "../horizon-shaderpack" }
 # Sound (ALSA on Linux); the `audio` feature.
 cpal = { version = "0.16", optional = true }
 symphonia = { version = "0.5", default-features = false, features = ["ogg", "vorbis"] }
@@ -78,8 +77,20 @@ default = ["audio", "controllers"]
 audio = ["dep:cpal"]
 # Controllers: gilrs, and the DualSense's own output. Without it only `horizon-ctl pad`'s virtual pad.
 controllers = ["dep:gilrs", "dep:horizon-dualsense"]
+# Runs code mods (wasmtime and cranelift: a quarter of a clean build). On in every release build
+# (release.yml); the tests and probes don't need it. Content mods load without it.
+mods = ["horizon-mods/runtime"]
 # Records the call sites of mob random draws (`mob_ai_probe` traces).
 rng-trace = ["horizon-core/rng-trace"]

+# Its own name, not `probe`: Cargo copies every crate's examples into one target/<profile>/examples.
+[[example]]
+name = "client_probe"
+path = "examples/probe/main.rs"
+
 [lints]
 workspace = true
+
+[dev-dependencies]
+# Every WGSL shader translated as wgpu's DirectX 12 backend does (gfx.rs tests).
+naga = { version = "30.0.1", features = ["wgsl-in", "hlsl-out", "msl-out", "spv-out"] }
@@ -41,7 +41,7 @@ pub fn main(names: &[&str], run: fn(&str) -> Option<ExitCode>) -> ExitCode {
    let name = std::env::args().nth(1).unwrap_or_default();
    run(&name).unwrap_or_else(|| {
        eprintln!(
-            "usage: probe <name> [arguments...]\nprobes: {}",
+            "usage: client_probe <name> [arguments...]\nprobes: {}",
            names.join(" ")
        );
        ExitCode::from(2)
@@ -293,6 +293,47 @@ fn spawn_seed(index: usize) -> i64 {
    1000 + 7919 * index as i64
 }

+/// `Villager.spawnGolemIfNeeded` for villager `a`, the game's way: the golem
+/// draws from the level's random and joins the scenario's mobs next tick,
+/// seeded as the oracle seeds what a tick spawned.
+fn summon_golem(
+    mobs: &mut [Mob],
+    a: usize,
+    needed: usize,
+    w: &MobWorld,
+    types: &MobTypes,
+    born: &mut Vec<Mob>,
+    level_random: &mut LegacyRandom,
+) {
+    use horizon_client::mobs::{villager, villager_brain};
+    let Some(near) = villager::golem_summoners(mobs, a, w.game_time, needed) else {
+        return;
+    };
+    let kind = Arc::new(
+        types
+            .types
+            .get("minecraft:iron_golem")
+            .expect("iron golem")
+            .clone(),
+    );
+    let index = mobs.len() + born.len();
+    let p = mobs[a].position;
+    let start = [p.x.floor() as i32, p.y.floor() as i32, p.z.floor() as i32];
+    let golem = villager::summon_golem(w, start, level_random, |random, at, yaw| {
+        let mut m = Mob::new(100_000 + index as u32, kind.clone(), at, yaw);
+        villager::finalize_summoned_golem(&mut m, random);
+        m
+    });
+    let Some(mut golem) = golem else {
+        return;
+    };
+    golem.random = LegacyRandom::new(spawn_seed(index));
+    born.push(golem);
+    for j in near {
+        villager_brain::golem_detected(&mut mobs[j], w.game_time);
+    }
+}
+
 /// Villager events that act at once in vanilla (`TradeWithVillager` and
 /// `VillagerMakeLove` write the other villager directly).
 fn villager_events(
@@ -304,6 +345,7 @@ fn villager_events(
    items: &Items,
    born: &mut Vec<Mob>,
    day_time: i64,
+    level_random: &mut LegacyRandom,
 ) {
    use horizon_client::mobs::villager;
    let index = |mobs: &[Mob], id: u32| {
@@ -314,6 +356,7 @@ fn villager_events(
    while i < events.len() {
        match events[i] {
            MobEvent::VillagerMeet { mob, other } => {
+                events.remove(i);
                if let (Some(a), Some(b)) = (index(mobs, mob), index(mobs, other)) {
                    let meeting = villager::meet(mobs, a, b, w.game_time, |item| {
                        items.get(item).map_or(64, |i| i.max_stack)
@@ -322,8 +365,16 @@ fn villager_events(
                        meeting.thrown.is_empty(),
                        "villagers toss items: not modelled here"
                    );
+                    if meeting.gossiped {
+                        summon_golem(mobs, a, 5, w, types, born, level_random);
+                    }
                }
+            }
+            MobEvent::GolemCheck { mob, needed } => {
                events.remove(i);
+                if let Some(a) = index(mobs, mob) {
+                    summon_golem(mobs, a, needed, w, types, born, level_random);
+                }
            }
            MobEvent::VillagerBirth {
                parent,
@@ -1167,6 +1218,7 @@ pub fn main() -> horizon_client::Result<()> {
                    &items,
                    &mut born,
                    s.time,
+                    &mut scratch,
                );
                horizon_client::mobs::warden::hear_mob_events(&mut mobs, &events, from, &w);
                // Melee hits on other mobs land during the attacker's tick
@@ -1323,6 +1375,31 @@ pub fn main() -> horizon_client::Result<()> {
                    world.set(at[0], at[1], at[2], registry.resolve(&st)?)?;
                }
            }
+            // Doors villagers opened or closed (DoorBlock.setOpen), both halves.
+            let doors: Vec<([i32; 3], bool)> = events
+                .iter()
+                .filter_map(|e| match e {
+                    MobEvent::SetDoorOpen { pos, open } => Some((*pos, *open)),
+                    _ => None,
+                })
+                .collect();
+            for (at, open) in doors {
+                let Some(half) = registry
+                    .state(world.block(at[0], at[1], at[2]))
+                    .and_then(|s| s.properties.get("half").cloned())
+                else {
+                    continue;
+                };
+                let other = if half == "lower" { 1 } else { -1 };
+                for y in [at[1], at[1] + other] {
+                    if let Some(mut st) = registry.state(world.block(at[0], y, at[2])).cloned()
+                        && st.properties.contains_key("open")
+                    {
+                        st.properties.insert("open".to_owned(), open.to_string());
+                        world.set(at[0], y, at[2], registry.resolve(&st)?)?;
+                    }
+                }
+            }
            mobs.append(&mut born);
            mobs.append(&mut added);
            for e in &heart_events {
@@ -5,7 +5,7 @@
 //!
 //! usage: pack_screen_fixture RESOURCES CASES OUTPUT
 use horizon_client::{
-    hud::HudAtlas,
+    hud::{HudAtlas, PACK_ICON_SIZE},
    lang,
    pack_screen::{Compat, PackInfo, PackScreen, Source},
    packs::{self, Position},
@@ -13,7 +13,7 @@ use horizon_client::{
    text::Text,
 };
 use serde_json::{Value, json};
-use std::{fmt::Write as _, fs, path::PathBuf};
+use std::{fmt::Write as _, fs, path::PathBuf, sync::Arc};

 /// Styled runs: [text, rgb or null, bold, italic, underlined, strikethrough, obfuscated].
 pub fn runs(t: &Text) -> Value {
@@ -105,7 +105,9 @@ pub fn main() -> horizon_client::Result<()> {
                        Some("unknown") => Compat::Unknown,
                        _ => Compat::Compatible,
                    },
-                    icon: p["icon"].as_bool().unwrap_or(false),
+                    icon: p["icon"].as_bool().unwrap_or(false).then(|| {
+                        Arc::from(vec![0; (PACK_ICON_SIZE * PACK_ICON_SIZE * 4) as usize])
+                    }),
                    required: p["required"].as_bool().unwrap_or(false),
                    position: if p["position"] == "top" {
                        Position::Top
@@ -136,7 +136,6 @@ fn scene(
        blend_radius,
        smooth_lighting,
        cutout_leaves,
-        cull_leaves: false,
    };
    let section_y = int(&row["section_y"])?;
    let started = Instant::now();
@@ -147,7 +147,6 @@ const PAGES: Ty = Ty::Enum(&[
    "graphics-advanced",
    "extras",
    "horizon",
-    "shader-packs",
    "agent",
 ]);

@@ -133,6 +133,30 @@ impl<W: EntityMovementWorld<Error = io::Error>> EntityMovementWorld for EntityCo
        border.collision_shape().map(Some).map_err(io::Error::other)
    }
 }
+impl EntityCollisions<'_, SceneCollisions<'_, '_>> {
+    /// `SceneCollisions::resolve` that also stops at the entity boxes.
+    pub fn resolve(
+        &mut self,
+        bounds: Aabb,
+        movement: Vec3,
+        max_step: f32,
+        on_ground: bool,
+    ) -> Result<Vec3> {
+        let context = self.blocks.context(bounds);
+        Ok(resolve_world_movement(
+            self,
+            MovementRequest {
+                entity: EntityIdentity(0),
+                context,
+                bounds,
+                movement,
+                max_step,
+                on_ground,
+                candidate_budget: 1_000_000,
+            },
+        )?)
+    }
+}
 impl SceneCollisions<'_, '_> {
    /// Position contexts permit geometric movement probes without inventing a
    /// player, inventory, effects or fluid-standing behavior; a lava walker
@@ -0,0 +1,75 @@
+//! `ConfirmScreen`: a title, a message wrapped to `width - 50` (15 lines at
+//! most) and two 150-wide buttons 4 apart and 16 below it, the whole column
+//! centred; Escape answers no.
+use crate::{
+    font::Font,
+    hud::{HudAtlas, HudBatch},
+    text::Text,
+    ui,
+};
+
+pub struct Confirm {
+    /// Each line and where it is drawn.
+    pub lines: Vec<(Text, f32, f32)>,
+    /// The yes and no buttons' corners.
+    pub buttons: [(f32, f32); 2],
+}
+impl Confirm {
+    pub fn new(font: &Font, (w, h): (f32, f32), title: &Text, message: &Text) -> Self {
+        let message: Vec<Text> = font
+            .split_lines(message, w - 50.0)
+            .into_iter()
+            .map(|(line, _)| line)
+            .take(15)
+            .collect();
+        let tw = font.width_text(title);
+        let mw = message
+            .iter()
+            .map(|l| font.width_text(l))
+            .fold(0.0, f32::max);
+        let mh = 9.0 * message.len() as f32;
+        let col = tw.max(mw).max(304.0);
+        let total = 9.0 + 8.0 + mh + 8.0 + 36.0;
+        let (lx, ly) = (((w - col) / 2.0).trunc(), ((h - total) / 2.0).trunc());
+        let cell = |cw: f32| lx + ((col - cw) / 2.0).trunc();
+        let mid = cell(mw) + (mw / 2.0).trunc();
+        let mut lines = vec![(title.clone(), cell(tw), ly)];
+        for (i, line) in message.into_iter().enumerate() {
+            let x = mid - (font.width_text(&line) / 2.0).trunc();
+            lines.push((line, x, ly + 17.0 + 9.0 * i as f32));
+        }
+        let (bx, by) = (cell(304.0), ly + 9.0 + 8.0 + mh + 8.0 + 16.0);
+        Self {
+            lines,
+            buttons: [(bx, by), (bx + 154.0, by)],
+        }
+    }
+    /// The answer a click at `cursor` gives: true for yes, false for no.
+    pub fn answer_at(&self, cursor: (f32, f32)) -> Option<bool> {
+        let [yes, no] = self.buttons;
+        let on = |(x, y): (f32, f32)| ui::hovered(cursor, x, y, 150.0, 20.0);
+        if on(yes) {
+            Some(true)
+        } else if on(no) {
+            Some(false)
+        } else {
+            None
+        }
+    }
+    /// The lines and the buttons (yes first), over whatever is behind.
+    pub fn draw(
+        &self,
+        batch: &mut HudBatch,
+        atlas: &HudAtlas,
+        cursor: (f32, f32),
+        labels: [&Text; 2],
+    ) {
+        for (line, x, y) in &self.lines {
+            batch.text_styled(atlas, line, *x, *y, u32::MAX, true);
+        }
+        for ((bx, by), label) in self.buttons.into_iter().zip(labels) {
+            let hover = ui::hovered(cursor, bx, by, 150.0, 20.0);
+            ui::button(batch, atlas, bx, by, 150.0, 20.0, label, true, hover);
+        }
+    }
+}
@@ -382,7 +382,7 @@ impl Providers {
        );
        Self { ints, floats }
    }
-    fn eval(&self, v: &Value, fast: bool, table: &HashMap<String, Value>, depth: u32) -> f64 {
+    fn eval(v: &Value, fast: bool, table: &HashMap<String, Value>, depth: u32) -> f64 {
        if depth > 16 {
            return 0.0;
        }
@@ -390,10 +390,10 @@ impl Providers {
            Value::Number(n) => n.as_f64().unwrap_or(0.0),
            Value::String(name) => table
                .get(name)
-                .map_or(0.0, |v| self.eval(v, fast, table, depth + 1)),
+                .map_or(0.0, |v| Self::eval(v, fast, table, depth + 1)),
            Value::Object(o) => {
                let f =
-                    |k: &str| self.eval(o.get(k).unwrap_or(&Value::Null), fast, table, depth + 1);
+                    |k: &str| Self::eval(o.get(k).unwrap_or(&Value::Null), fast, table, depth + 1);
                match o.get("type").and_then(Value::as_str).unwrap_or("") {
                    "minecraft:div" => {
                        let r = f("right");
@@ -425,14 +425,14 @@ impl Providers {
    }
    /// A plain `context_int_provider` value or reference (no context conditions).
    pub fn int_value(&self, v: &Value) -> i32 {
-        self.eval(v, false, &self.ints, 0) as i32
+        Self::eval(v, false, &self.ints, 0) as i32
    }
    /// A plain `context_float_provider` value or reference; `default` when absent.
    pub fn float_value(&self, v: &Value, default: f32) -> f32 {
        if v.is_null() {
            default
        } else {
-            self.eval(v, false, &self.floats, 0) as f32
+            Self::eval(v, false, &self.floats, 0) as f32
        }
    }
    #[cfg(test)]
@@ -446,14 +446,14 @@ impl Providers {
        items
            .get(&stack.item)
            .and_then(|i| i.fuel.as_ref())
-            .map_or(0, |(time, _)| self.eval(time, fast, &self.ints, 0) as i32)
+            .map_or(0, |(time, _)| Self::eval(time, fast, &self.ints, 0) as i32)
    }
    pub fn speed(&self, items: &Items, stack: &ItemStack, fast: bool) -> f32 {
        items
            .get(&stack.item)
            .and_then(|i| i.fuel.as_ref())
            .map_or(1.0, |(_, speed)| {
-                self.eval(speed, fast, &self.floats, 0) as f32
+                Self::eval(speed, fast, &self.floats, 0) as f32
            })
    }
 }
@@ -425,6 +425,29 @@ fn split_id(id: &str) -> (String, String) {
        None => ("minecraft".to_owned(), id.to_owned()),
    }
 }
+/// The slot under the cursor, for the search tab's keys.
+#[derive(Clone, Copy, PartialEq, Eq, Debug)]
+pub enum Hover {
+    Nothing,
+    /// A display slot (`isCreativeSlot`), showing an item or past the end.
+    Display {
+        filled: bool,
+    },
+    /// Any other slot: the hotbar row, or the inventory tab's slots.
+    Slot,
+}
+
+/// `CreativeModeInventoryScreen.keyPressed` on the search tab: whether a
+/// key is a hotbar swap on the hovered slot instead of text for the search
+/// box. `numeric` is `getNumericKeyValue().isPresent()` (the digit and keypad
+/// keys); `hotbar_key` is a `keyHotbarSlots` key. Over an empty display slot
+/// the key types (`doQuickSwap` is false), and `checkHotbarKeyPressed` needs
+/// a hovered slot and an empty cursor.
+pub fn search_key_swaps(numeric: bool, hotbar_key: bool, hover: Hover, carrying: bool) -> bool {
+    let quick_swap = hover != Hover::Display { filled: false };
+    quick_swap && numeric && hotbar_key && !carrying && hover != Hover::Nothing
+}
+
 /// What a click on an item tab's display slot does besides changing the
 /// carried stack.
 #[derive(Clone, PartialEq, Debug)]
@@ -529,6 +552,22 @@ mod tests {
        (carried, effect)
    }

+    #[test]
+    fn search_tab_number_keys_swap_over_a_slot_before_typing() {
+        let filled = Hover::Display { filled: true };
+        let empty = Hover::Display { filled: false };
+        // Over an item, the hotbar row or another slot: the hotbar swap.
+        assert!(search_key_swaps(true, true, filled, false));
+        assert!(search_key_swaps(true, true, Hover::Slot, false));
+        // Over an empty display slot, nothing or with a carried stack: text.
+        assert!(!search_key_swaps(true, true, empty, false));
+        assert!(!search_key_swaps(true, true, Hover::Nothing, false));
+        assert!(!search_key_swaps(true, true, filled, true));
+        // Letters always type; so do the digits no hotbar key is bound to.
+        assert!(!search_key_swaps(false, false, filled, false));
+        assert!(!search_key_swaps(true, false, filled, false));
+    }
+
    #[test]
    fn display_slot_clicks_follow_slot_clicked() {
        use crate::menu::Input::*;
@@ -137,6 +137,48 @@ pub fn item_pose(left: bool, inverse_height: f32, attack: f32, pose: ItemPose) -
    m
 }

+/// How `submitArmWithItem` holds a stack with a `minecraft:map_id`: in both
+/// hands when it is the main hand's and the off hand is empty
+/// (`renderTwoHandedMap`), else in its own hand (`renderOneHandedMap`).
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum MapHold {
+    TwoHanded,
+    OneHanded,
+}
+impl MapHold {
+    pub fn of(hand: Hand, off_hand_empty: bool) -> Self {
+        if hand == Hand::Main && off_hand_empty {
+            Self::TwoHanded
+        } else {
+            Self::OneHanded
+        }
+    }
+}
+
+/// `renderOneHandedMap` up to `renderMap`: the pose of a map in the hand on
+/// the `left` or right arm (the arm under it is not drawn).
+pub fn one_handed_map_pose(left: bool, inverse_height: f32, attack: f32) -> glam::Mat4 {
+    use glam::{Mat4, Vec3};
+    use horizon_core::geometry::trig::Mth;
+    let invert = if left { -1.0 } else { 1.0 };
+    let pi = std::f32::consts::PI;
+    let root = attack.sqrt();
+    let x_swing = (root * pi).msin();
+    Mat4::from_translation(Vec3::new(invert * 0.125, -0.125, 0.0))
+        * Mat4::from_translation(Vec3::new(
+            invert * 0.51,
+            -0.08 + inverse_height * -1.2,
+            -0.75,
+        ))
+        * Mat4::from_translation(Vec3::new(
+            invert * -0.5 * x_swing,
+            0.4 * (root * std::f32::consts::TAU).msin() - 0.3 * x_swing,
+            -0.3 * (attack * pi).msin(),
+        ))
+        * Mat4::from_rotation_x((x_swing * -45.0).to_radians())
+        * Mat4::from_rotation_y((invert * x_swing * -30.0).to_radians())
+}
+
 /// `FirstPersonHandsAndItems.evaluateWhichHandsToRender`: whether the main
 /// and the off hand show, from what each holds (item and whether it is a
 /// charged crossbow) and the item in use with its hand. A bow or crossbow
@@ -819,6 +861,84 @@ mod tests {
 mod item_pose_tests {
    use super::*;
    #[test]
+    fn a_map_is_two_handed_only_in_the_main_hand_with_an_empty_off_hand() {
+        assert_eq!(MapHold::of(Hand::Main, true), MapHold::TwoHanded);
+        assert_eq!(MapHold::of(Hand::Main, false), MapHold::OneHanded);
+        assert_eq!(MapHold::of(Hand::Off, true), MapHold::OneHanded);
+        assert_eq!(MapHold::of(Hand::Off, false), MapHold::OneHanded);
+    }
+    #[test]
+    fn one_handed_maps_follow_render_one_handed_map() {
+        // PoseStack.last().pose() from vanilla's renderOneHandedMap
+        // transforms (column-major), for (left, inverse height, attack).
+        let cases: [(bool, f32, f32, [f32; 16]); 3] = [
+            (
+                false,
+                0.0,
+                0.0,
+                [
+                    1.0, 0.0, 0.0, 0.0, 0.0, 1.0, -0.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.635, -0.205,
+                    -0.75, 1.0,
+                ],
+            ),
+            (
+                true,
+                0.25,
+                0.3,
+                [
+                    0.86894435,
+                    -0.34686038,
+                    -0.35302067,
+                    0.0,
+                    0.0,
+                    0.713303,
+                    -0.70085573,
+                    0.0,
+                    0.4949098,
+                    0.6090046,
+                    0.61982065,
+                    0.0,
+                    -0.1406033,
+                    -0.9197687,
+                    -0.9926984,
+                    1.0,
+                ],
+            ),
+            (
+                false,
+                0.6,
+                0.85,
+                [
+                    0.9919303,
+                    0.024030307,
+                    0.12448644,
+                    0.0,
+                    0.0,
+                    0.9818737,
+                    -0.18953651,
+                    0.0,
+                    -0.12678458,
+                    0.18800701,
+                    0.97395027,
+                    0.0,
+                    0.5136029,
+                    -1.1862278,
+                    -0.88621765,
+                    1.0,
+                ],
+            ),
+        ];
+        for (left, inverse_height, attack, want) in cases {
+            let got = one_handed_map_pose(left, inverse_height, attack).to_cols_array();
+            for (g, w) in got.iter().zip(want) {
+                assert!(
+                    (g - w).abs() < 1e-5,
+                    "{left} {inverse_height} {attack}: {got:?}"
+                );
+            }
+        }
+    }
+    #[test]
    fn ranged_draw_uses_native_charge_curves_and_caps() {
        for (ticks, stretch) in [
            (0.0, 1.0),
@@ -102,7 +102,8 @@ enum Provider {
 /// One font (`FontSet`): its providers and the glyphs resolved so far.
 struct FontSet {
    providers: Vec<Provider>,
-    glyphs: HashMap<char, Glyph>,
+    /// Every char drawn looks up here, so the hasher is Fx, not SipHash.
+    glyphs: crate::fast_hash::FxHashMap<char, Glyph>,
    /// `glyphsByWidth` for obfuscated text (built on first use).
    by_width: Option<HashMap<u32, Vec<char>>>,
 }
@@ -647,7 +648,7 @@ impl Font {
            .collect();
        FontSet {
            providers,
-            glyphs: HashMap::new(),
+            glyphs: Default::default(),
            by_width: None,
        }
    }
@@ -13,6 +13,7 @@ mod block_entity_anims;
 mod block_entity_ticks;
 mod block_items;
 mod blockctl;
+mod boat_passengers;
 mod boats;
 mod books;
 mod bossbars;
@@ -137,8 +138,8 @@ mod scoreboard;
 mod screens;
 mod sculk;
 mod sculk_fixture;
+mod server_packs;
 mod server_travel;
-mod shader_packs;
 mod shield;
 mod sign_edit;
 mod sniffers;
@@ -285,11 +286,9 @@ struct Options {
    benchmark: Option<String>,
    /// `--dev-mod PATH` (repeatable): mods always on and reloaded when rebuilt.
    dev_mods: Vec<PathBuf>,
-    /// `--server-thread` or `HORIZON_SERVER_THREAD=1`: single player runs on an
-    /// integrated server thread (game/integrated.rs), as vanilla's does. Off by
-    /// default again until a server's players reach parity with the in-frame
-    /// world (signs, books, totems, keep_inventory...); `--no-server-thread`
-    /// keeps it off.
+    /// Single player runs on an integrated server thread (game/integrated.rs),
+    /// as vanilla's does: the default. `--in-frame` (or `--no-server-thread`,
+    /// or `HORIZON_SERVER_THREAD=0`) runs the world in the frame instead.
    server_thread: bool,
    /// Set on the integrated server's own options: it draws nothing, so it skips meshing.
    integrated: bool,
@@ -347,7 +346,7 @@ impl Options {
            dev_mods: Vec::new(),
            // The command harness (HORIZON_COMMAND_SCRIPT) drives the world
            // itself, without the event loop: it stays in the frame.
-            server_thread: std::env::var("HORIZON_SERVER_THREAD").is_ok_and(|v| v == "1")
+            server_thread: std::env::var("HORIZON_SERVER_THREAD").map_or(true, |v| v != "0")
                && std::env::var_os("HORIZON_COMMAND_SCRIPT").is_none(),
            integrated: false,
        };
@@ -357,7 +356,7 @@ impl Options {
            match arg.as_str() {
                "--help" | "-h" => {
                    println!(
-                        "Horizon — Minecraft Java Edition {} in Rust\n\n  --resources PATH        Prepared resources (horizon-prepare)\n  --render-distance N     Chunks, 2..64 (default 12)\n  --world NAME            World folder under saves/ (default \"New World\")\n  --seed N                World seed for new worlds (default 0)\n  --width N, --height N   Window size (default 1280 x 720)\n  --creative              Creative mode (default survival)\n  --test-terrain          Simple test terrain instead of vanilla generation\n  --frames N              Exit after N frames (testing)\n  --world-frames N        Exit after N frames drawn in the world (testing)\n  --smoke-report PATH     Write a JSON report on exit\n  --benchmark SCENARIO    Run a benchmark (standard, village, forest, ocean, mountain), write its report to benchmarks/ and quit\n  --control               Accept horizon-ctl commands on a local socket\n  --control-socket PATH   Control socket path (default $XDG_RUNTIME_DIR/horizon-control.sock)\n  --server HOST[:PORT]    Join a multiplayer server (offline mode) at start\n  --name NAME             Player name for multiplayer (default: generated once, kept in horizon-player.txt)\n  --session-file PATH     Signed-in account from the launcher (read once, then deleted)\n  --dev-mod PATH          A Horizon mod (.hmod or folder) to develop: always on, reloaded when rebuilt\n  --server-thread         Run single player's world on its server thread (not at parity yet)\n\nControls: mouse look, WASD move, Space jump, Left Shift sneak, Left Ctrl sprint,\nleft click break, right click place/use, 1-9/scroll hotbar, E inventory,\nQ drop, F3 debug, Esc pause.",
+                        "Horizon — Minecraft Java Edition {} in Rust\n\n  --resources PATH        Prepared resources (horizon-prepare)\n  --render-distance N     Chunks, 2..64 (default 12)\n  --world NAME            World folder under saves/ (default \"New World\")\n  --seed N                World seed for new worlds (default 0)\n  --width N, --height N   Window size (default 1280 x 720)\n  --creative              Creative mode (default survival)\n  --test-terrain          Simple test terrain instead of vanilla generation\n  --frames N              Exit after N frames (testing)\n  --world-frames N        Exit after N frames drawn in the world (testing)\n  --smoke-report PATH     Write a JSON report on exit\n  --benchmark SCENARIO    Run a benchmark (standard, village, forest, ocean, mountain), write its report to benchmarks/ and quit\n  --control               Accept horizon-ctl commands on a local socket\n  --control-socket PATH   Control socket path (default $XDG_RUNTIME_DIR/horizon-control.sock)\n  --server HOST[:PORT]    Join a multiplayer server (offline mode) at start\n  --name NAME             Player name for multiplayer (default: generated once, kept in horizon-player.txt)\n  --session-file PATH     Signed-in account from the launcher (read once, then deleted)\n  --dev-mod PATH          A Horizon mod (.hmod or folder) to develop: always on, reloaded when rebuilt\n  --in-frame              Run single player's world in the frame, not on its server thread\n\nControls: mouse look, WASD move, Space jump, Left Shift sneak, Left Ctrl sprint,\nleft click break, right click place/use, 1-9/scroll hotbar, E inventory,\nQ drop, F3 debug, Esc pause.",
                        horizon_core::VANILLA_VERSION
                    );
                    return Ok(None);
@@ -372,7 +371,7 @@ impl Options {
                "--offscreen" => o.offscreen = true,
                "--control" => o.control = Some(horizon_client::control::default_path()),
                "--server-thread" => o.server_thread = true,
-                "--no-server-thread" => o.server_thread = false,
+                "--in-frame" | "--no-server-thread" => o.server_thread = false,
                _ => {
                    let value = args
                        .next()
@@ -1129,6 +1128,8 @@ struct Game<'a> {
    pending_entry: Option<PendingWorldEntry>,
    world_loader: Option<world_loading::WorldLoader>,
    pending_pack_reload: bool,
+    /// A server's resource packs (game/server_packs.rs).
+    server_packs: server_packs::ServerPackState,
    world_renderer_ready: bool,
    collision: &'a BlockCollisionRegistry<'a>,
    motion: &'a MotionResources,
@@ -1201,8 +1202,6 @@ struct Game<'a> {
    modifiers: winit::keyboard::ModifiersState,
    /// The window's fullscreen request and reported state.
    fullscreen: horizon_client::window::FullscreenState,
-    /// The selected Horizon shader pack (`game/shader_packs.rs`).
-    shader_packs: shader_packs::ShaderPacks,
    /// MouseHandler's accumulated look and wheel state.
    mouse: MouseLook,
    /// An agent moved the mouse (`mouse-move`) since the pointer was last
@@ -1446,6 +1445,8 @@ struct Game<'a> {
    mount_menu: mount_menu::MountMenu,
    /// The player's fishing hook.
    hook: Option<fishing::Hook>,
+    /// The other players' hooks a server tracks to this client.
+    remote_hooks: Vec<fishing::RemoteHook>,
    tridents: Vec<trident::ThrownTrident>,
    rockets: Vec<fireworks::Rocket>,
    /// Ominous trial spawners' item spawners.
@@ -1741,10 +1742,10 @@ impl Game<'_> {
            let state = self.world.block(pos[0], pos[1], pos[2]);
            let f = self.res.facts().get(state);
            if !self.res.facts().is_air(state)
-                && !(f.fluid != Fluid::None
-                    && !f.waterlogged
-                    && &*f.name != "minecraft:kelp"
-                    && f.render_shape != horizon_client::blocks::RenderShape::Model)
+                && (f.fluid == Fluid::None
+                    || f.waterlogged
+                    || &*f.name == "minecraft:kelp"
+                    || f.render_shape == horizon_client::blocks::RenderShape::Model)
                && !matches!(
                    &*f.name,
                    "minecraft:water" | "minecraft:lava" | "minecraft:bubble_column"
@@ -1817,6 +1818,65 @@ impl Game<'_> {
        self.stack_in_mut(self.held_slot())
    }
    /// The slot of the hand that acts: the selected one, or `OFFHAND_SLOT`.
+    /// `LivingEntity.canGlideUsing`: a glider in the chest slot that will
+    /// not break with its next point of wear.
+    fn glider_worn(&self) -> bool {
+        self.armor[1].as_ref().is_some_and(|s| {
+            self.res
+                .items()
+                .get(&s.item)
+                .is_some_and(|i| i.glider && (i.max_damage == 0 || s.damage + 1 < i.max_damage))
+        })
+    }
+    /// What the window decides for its player's body every tick, in frame and
+    /// on a server alike: the look (Player.travel steers sprint-swimming by
+    /// the pitch), Auto Jump (LocalPlayer.sendPosition), the slowdown of an
+    /// item in use (LocalPlayer.modifyInput), the helmet's Respiration
+    /// (decreaseAirSupply), the wings, leather boots on powder snow
+    /// (PowderSnowBlock.canEntityWalkOnPowderSnow), freeze-immune wear
+    /// (LivingEntity.canFreeze) and the dimension's FAST_LAVA.
+    pub(crate) fn sync_player_body(&mut self) {
+        let glider = self.glider_worn();
+        let item_use_speed = self
+            .using
+            .and_then(|(slot, _)| {
+                if slot == shield::OFFHAND_SLOT {
+                    self.offhand.as_ref()
+                } else {
+                    self.inventory.get(slot)?.as_ref()
+                }
+            })
+            .and_then(|s| self.res.items().get(&s.item))
+            .map(|i| i.use_speed);
+        let respiration = self.armor[0]
+            .as_ref()
+            .map_or(0, |s| s.enchantment_level("minecraft:respiration") as i32);
+        let leather_boots = self.armor[3]
+            .as_ref()
+            .is_some_and(|s| &*s.item == "minecraft:leather_boots");
+        let immune = self
+            .res
+            .items()
+            .item_tags
+            .get("minecraft:freeze_immune_wearables");
+        let freeze_immune = self
+            .armor
+            .iter()
+            .flatten()
+            .any(|s| immune.is_some_and(|t| t.contains(&*s.item)));
+        let Some(player) = self.player.as_mut() else {
+            return;
+        };
+        player.yaw = self.yaw;
+        player.pitch = self.pitch;
+        player.auto_jump_enabled = self.settings.auto_jump;
+        player.item_use_speed = item_use_speed;
+        player.respiration = respiration;
+        player.glider = glider;
+        player.leather_boots = leather_boots;
+        player.freeze_immune = freeze_immune;
+        player.fluids.fast_lava = self.dim == Dim::Nether;
+    }
    fn held_slot(&self) -> usize {
        match self.hand {
            Hand::Main => self.selected,
@@ -1994,6 +2054,28 @@ impl Game<'_> {
        particle.scale(0.6);
        self.particles.push(particle);
    }
+    /// `Player.dropEquipment` for the player who died: unless keep_inventory
+    /// is on, `destroyVanishingCursedItems`, then `Inventory.dropAll` from
+    /// `at` (the eyes less 0.3): slots 0..36, armor feet to head (36..39),
+    /// the off hand (40), each thrown in a random direction.
+    fn drop_inventory(&mut self, at: [f64; 3]) {
+        if self.ui.rules.bool("keep_inventory") {
+            return;
+        }
+        let mut stacks: Vec<ItemStack> =
+            self.inventory.iter_mut().filter_map(Option::take).collect();
+        stacks.extend(self.armor.iter_mut().rev().filter_map(Option::take));
+        stacks.extend(self.offhand.take());
+        stacks.retain(|s| s.enchantment_level("minecraft:vanishing_curse") == 0);
+        self.apply_equipment();
+        for stack in stacks {
+            let r = &mut self.world.random;
+            let strength = f64::from(r.next_float()) * 0.5;
+            let angle = f64::from(r.next_float()) * std::f64::consts::TAU;
+            let v = [-angle.sin() * strength, 0.2, angle.cos() * strength];
+            self.spawn_item(stack, at, v, 40);
+        }
+    }
    fn spawn_item(
        &mut self,
        stack: ItemStack,
@@ -3429,7 +3511,7 @@ impl Game<'_> {
            return Ok(true);
        }
        // Block foods attempt placement before starting consumption.
-        if !on_block && !(info.block.is_some() && block_hit.is_some()) && self.start_eating(&info) {
+        if !on_block && (info.block.is_none() || block_hit.is_none()) && self.start_eating(&info) {
            return Ok(true);
        }
        // BoatItem.use also performs its own fluid/block raycast.
@@ -3649,16 +3731,8 @@ impl Game<'_> {
        // Switching hotbar slots only ends a main-hand use.
        let hand_changed = slot != self.selected && slot != shield::OFFHAND_SLOT;
        if !self.right || hand_changed || self.screen != Screen::Playing {
-            if &*stack.item == "minecraft:bow" && !hand_changed {
-                self.release_bow(ticks);
-            }
-            if &*stack.item == "minecraft:spyglass" {
-                self.stop_spyglass();
-            }
-            if &*stack.item == "minecraft:trident" && !hand_changed {
-                self.release_trident(ticks);
-            }
            self.using = None;
+            self.release_used_item(&stack, ticks, hand_changed);
            return;
        }
        let Some(info) = self.res.items().get(&stack.item).cloned() else {
@@ -3714,6 +3788,17 @@ impl Game<'_> {
            self.using = Some((slot, ticks));
        }
    }
+    /// `LivingEntity.releaseUsingItem` (`Item.releaseUsing`) for `stack`,
+    /// used for `ticks`, its hand acting: a bow or a trident lets go (not
+    /// when its hand changed), a spyglass stops scoping.
+    pub(super) fn release_used_item(&mut self, stack: &ItemStack, ticks: u32, hand_changed: bool) {
+        match &*stack.item {
+            "minecraft:bow" if !hand_changed => self.release_bow(ticks),
+            "minecraft:trident" if !hand_changed => self.release_trident(ticks),
+            "minecraft:spyglass" => self.stop_spyglass(),
+            _ => {}
+        }
+    }
    fn tick_mining(&mut self) -> Result<()> {
        if self.destroy_delay > 0 {
            self.destroy_delay -= 1;
@@ -3803,7 +3888,12 @@ impl Game<'_> {
        }
        self.crack_particle(crack.0, crack.1, state);
        let m = self.mining.as_mut().ok_or("mining")?;
-        if m.progress >= 1.0 {
+        // ServerPlayerGameMode breaks a player's block at once only when it is instant (START's
+        // insta-mine); otherwise it waits for the client's STOP_DESTROY_BLOCK
+        // (`guest_stop_digging`), never breaking it on its own count. Breaking it here would
+        // take the block from under the player's crack before the player's client predicts the
+        // break, so it gets neither particles nor sound.
+        if m.progress >= 1.0 && (self.lan_acting.is_none() || m.ticks == 1) {
            let pos = m.pos;
            self.mining = None;
            self.break_block(pos)?;
@@ -3937,13 +4027,7 @@ impl Game<'_> {
            .as_ref()
            .map_or(0, |s| s.enchantment_level("minecraft:respiration") as i32);
        player.pitch = self.pitch;
-        // LivingEntity.canGlideUsing: a glider in its slot that will not break next.
-        player.glider = self.armor[1].as_ref().is_some_and(|s| {
-            self.res
-                .items()
-                .get(&s.item)
-                .is_some_and(|i| i.glider && (i.max_damage == 0 || s.damage + 1 < i.max_damage))
-        });
+        player.glider = self.glider_worn();
        // A saved death already dropped inventory/XP and counted the death.
        if player.health.dead_or_dying() {
            self.screen = Screen::Dead;
@@ -4019,8 +4103,9 @@ impl Game<'_> {
            self.tick_riding(keys)?;
        }
        let riding = self.riding.is_some();
-        let ghast_collisions = self.happy_ghast_player_collisions();
+        let entity_collisions = self.player_entity_collisions();
        let spin_targets = self.spin_targets();
+        self.sync_player_body();
        let Some(player) = self.player.as_mut() else {
            // A dedicated server has no local player: the world still runs.
            if self.options.dedicated.is_some() {
@@ -4052,52 +4137,10 @@ impl Game<'_> {
        if !riding {
            self.previous_position = player.position;
        }
-        player.yaw = self.yaw;
        let spectator = self.mode == horizon_client::command::args::GameMode::Spectator;
        player.may_fly = self.creative || spectator;
-        // LocalPlayer.sendPosition: autoJumpEnabled follows the option.
-        player.auto_jump_enabled = self.settings.auto_jump;
        player.invulnerable = self.creative || spectator;
        player.spectator = spectator;
-        player.respiration = self.armor[0]
-            .as_ref()
-            .map_or(0, |s| s.enchantment_level("minecraft:respiration") as i32);
-        player.pitch = self.pitch;
-        // LivingEntity.canGlideUsing: a glider in its slot that will not break next.
-        player.glider = self.armor[1].as_ref().is_some_and(|s| {
-            self.res
-                .items()
-                .get(&s.item)
-                .is_some_and(|i| i.glider && (i.max_damage == 0 || s.damage + 1 < i.max_damage))
-        });
-        // LocalPlayer.modifyInput: walking while using an item.
-        player.item_use_speed = self
-            .using
-            .and_then(|(slot, _)| {
-                if slot == shield::OFFHAND_SLOT {
-                    self.offhand.as_ref()
-                } else {
-                    self.inventory.get(slot)?.as_ref()
-                }
-            })
-            .and_then(|s| self.res.items().get(&s.item))
-            .map(|i| i.use_speed);
-        // PowderSnowBlock.canEntityWalkOnPowderSnow and LivingEntity.canFreeze.
-        player.leather_boots = self.armor[3]
-            .as_ref()
-            .is_some_and(|s| &*s.item == "minecraft:leather_boots");
-        let immune = self
-            .res
-            .items()
-            .item_tags
-            .get("minecraft:freeze_immune_wearables");
-        player.freeze_immune = self
-            .armor
-            .iter()
-            .flatten()
-            .any(|s| immune.is_some_and(|t| t.contains(&*s.item)));
-        // The dimension's FAST_LAVA: the Nether's lava pushes harder.
-        player.fluids.fast_lava = self.dim == Dim::Nether;
        player.spin_targets = spin_targets;
        let grounded = player.ground.on_ground;
        let before = (
@@ -4107,7 +4150,7 @@ impl Game<'_> {
        );
        if !riding {
            MotionWorld {
-                entities: &ghast_collisions,
+                entities: &entity_collisions,
                player,
                scene: &mut self.world,
                assets: &self.pack.assets,
@@ -4306,20 +4349,8 @@ impl Game<'_> {
                .experience
                .death_reward(self.ui.rules.bool("keep_inventory") || self.spectator());
            self.spawn_orbs(feet, reward);
-            if !self.creative && !self.ui.rules.bool("keep_inventory") {
-                // Inventory.dropAll: slots 0..36, armor feet to head (36..39), off hand (40).
-                let mut stacks: Vec<ItemStack> =
-                    self.inventory.iter_mut().filter_map(Option::take).collect();
-                stacks.extend(self.armor.iter_mut().rev().filter_map(Option::take));
-                stacks.extend(self.offhand.take());
-                self.apply_equipment();
-                for stack in stacks {
-                    let r = &mut self.world.random;
-                    let strength = f64::from(r.next_float()) * 0.5;
-                    let angle = f64::from(r.next_float()) * std::f64::consts::TAU;
-                    let v = [-angle.sin() * strength, 0.2, angle.cos() * strength];
-                    self.spawn_item(stack, at, v, 40);
-                }
+            if !self.spectator() {
+                self.drop_inventory(at);
            }
            self.audio
                .play("minecraft:entity.player.death", Some(at), 1.0, 1.0);
@@ -4383,7 +4414,7 @@ impl Game<'_> {
                self.resolve_arrivals();
            });
        }
-        horizon_client::spans::time("tick_lan", || self.tick_lan());
+        horizon_client::spans::time("tick_lan", || self.tick_lan(false));
        self.tick_friends();
        horizon_client::spans::time("tick_hand", || self.tick_hand());
        horizon_client::spans::time("tick_sleep", || self.tick_sleep());
@@ -4744,7 +4775,14 @@ impl Game<'_> {
        hud_layout::paint(batch, &self.gui.atlas, &draws);
    }
    fn hud(&mut self, size: [u32; 2]) -> HudBatch {
-        let mut batch = self.hud_layers(size);
+        // The pack prompt replaces the connecting screen (setScreen), but
+        // in game it opens over the world.
+        let mut batch = if self.server_packs.prompt.is_some() && self.player.is_none() {
+            HudBatch::new(size)
+        } else {
+            self.hud_layers(size)
+        };
+        self.draw_pack_prompt(&mut batch);
        // Gui.extractRenderState: the debug overlay comes after the screen
        // and the toasts, so it is over everything, menus included.
        self.draw_debug_overlay(&mut batch, size);
@@ -5992,6 +6030,37 @@ impl Game<'_> {
        }
        true
    }
+    /// `CreativeModeInventoryScreen.keyPressed` on the search tab: a hotbar
+    /// key over a slot swaps before the search box sees it.
+    fn search_tab_hotbar_key(&mut self, code: KeyCode) -> bool {
+        use horizon_client::creative::{Hover, search_key_swaps};
+        let hotbar_key = HOTBAR_DIGITS.contains(&code);
+        let numeric = hotbar_key || NUMERIC_KEYS.contains(&code);
+        if !numeric {
+            return false;
+        }
+        let Some(size) = self
+            .renderer
+            .as_ref()
+            .map(|r| [r.config.width, r.config.height])
+        else {
+            return false;
+        };
+        let batch = HudBatch::new(size);
+        let hover = match self.slot_at(&batch, self.cursor.0, self.cursor.1) {
+            None => Hover::Nothing,
+            Some(slot) if slot >= Creative::DISPLAY => {
+                let first = self.creative_screen.first_row(&self.pack.names);
+                let shown = self.creative_screen.items(&self.pack.names).len();
+                Hover::Display {
+                    filled: first * 9 + slot - Creative::DISPLAY < shown,
+                }
+            }
+            Some(_) => Hover::Slot,
+        };
+        search_key_swaps(numeric, hotbar_key, hover, self.carried.is_some())
+            && self.inventory_hotkey(code)
+    }
    /// Number keys, F and Q over a slot of the open menu: SWAP with a hotbar
    /// slot or the off hand, THROW one or the whole stack.
    fn inventory_hotkey(&mut self, key: KeyCode) -> bool {
@@ -6007,19 +6076,7 @@ impl Game<'_> {
        let Some(slot) = self.slot_at(&batch, self.cursor.0, self.cursor.1) else {
            return false;
        };
-        let digit = [
-            KeyCode::Digit1,
-            KeyCode::Digit2,
-            KeyCode::Digit3,
-            KeyCode::Digit4,
-            KeyCode::Digit5,
-            KeyCode::Digit6,
-            KeyCode::Digit7,
-            KeyCode::Digit8,
-            KeyCode::Digit9,
-        ]
-        .iter()
-        .position(|k| *k == key);
+        let digit = HOTBAR_DIGITS.iter().position(|k| *k == key);
        let done = match (digit, key) {
            (Some(n), _) => self.menu_click(Some(slot), n as i32, Input::Swap),
            (None, KeyCode::KeyF) => self.menu_click(Some(slot), 40, Input::Swap),
@@ -7385,30 +7442,17 @@ impl Game<'_> {
        self.tick_player_model();
        Ok(())
    }
-    /// What the loaded Java shader pack changes in this dimension's vanilla
-    /// sky (`sunPathRotation`, `clouds`, `sun`, `moon`); `None` without one.
-    fn java_sky(&self) -> Option<(f32, horizon_shaderpack::properties::SkyDirectives)> {
-        self.shader_packs.java_sky(match self.dim {
-            Dim::Overworld => 0,
-            Dim::Nether => -1,
-            Dim::End => 1,
-        })
-    }
    /// SkyRenderer.renderSunMoonAndStars: bodies on a frame rotated Y -90 then X by angle.
-    /// A Java pack's `sunPathRotation` tilts it about Z in between, and its
-    /// `sun = false` / `moon = false` leave those out, as Iris does. Returns
-    /// the sun and moon quads, and the stars' frame and brightness (the
-    /// renderer keeps their geometry, built once).
+    /// Returns the sun and moon quads, and the stars' frame and brightness
+    /// (the renderer keeps their geometry, built once).
    fn celestial_geometry(
        &self,
        sky: &horizon_client::environment::Sky,
    ) -> (Vec<Vertex>, Option<(glam::Mat4, f32)>) {
        let mut out = Vec::new();
        let atlas = &self.gui.atlas;
-        let (tilt, keep) = self.java_sky().unwrap_or_default();
        let frame = |angle: f32| {
            glam::Mat4::from_rotation_y((-90.0f32).to_radians())
-                * glam::Mat4::from_rotation_z(tilt.to_radians())
                * glam::Mat4::from_rotation_x(angle.to_radians())
        };
        let mut body = |name: &str, angle: f32, size: f32, color: u32| {
@@ -7430,14 +7474,12 @@ impl Game<'_> {
                });
            }
        };
-        if keep.sun {
-            body(
-                "environment/celestial/sun",
-                sky.sun_angle,
-                30.0,
-                0xFFFF_FFFF,
-            );
-        }
+        body(
+            "environment/celestial/sun",
+            sky.sun_angle,
+            30.0,
+            0xFFFF_FFFF,
+        );
        let phases = [
            "full_moon",
            "waning_gibbous",
@@ -7449,14 +7491,12 @@ impl Game<'_> {
            "waxing_gibbous",
        ];
        let phase = phases[(self.world.day_time / 24000).rem_euclid(8) as usize];
-        if keep.moon {
-            body(
-                &format!("environment/celestial/moon/{phase}"),
-                sky.moon_angle,
-                20.0,
-                0xFFFF_FFFF,
-            );
-        }
+        body(
+            &format!("environment/celestial/moon/{phase}"),
+            sky.moon_angle,
+            20.0,
+            0xFFFF_FFFF,
+        );
        // SkyRenderer.renderStars: the static star buffer on the same frame.
        let stars =
            (sky.star_brightness > 0.0).then(|| (frame(sky.star_angle), sky.star_brightness));
@@ -8846,20 +8886,15 @@ impl Game<'_> {
        );
        let packed = (u32::from(light >> 4) * 16) | ((u32::from(light & 15) * 16) << 8);
        let deg = |d: f32| d.to_radians();
-        if self.held_map_geometry(to_world, attacks[0], inverse_heights[0], packed, &mut out) {
-            return out;
-        }
        let shown = self.hands_to_render();
        let used_hand = self.used_hand();
        let spinning = self
            .player
            .as_ref()
            .is_some_and(|p| p.auto_spin_attack_ticks > 0);
-        for (i, (hand, item)) in Hand::BOTH
-            .into_iter()
-            .zip(self.visible_hand_items())
-            .enumerate()
-        {
+        let items = self.visible_hand_items();
+        let off_hand_empty = items[1].is_none();
+        for (i, (hand, item)) in Hand::BOTH.into_iter().zip(items).enumerate() {
            if !shown[i] {
                continue;
            }
@@ -8922,6 +8957,26 @@ impl Game<'_> {
                );
                continue;
            };
+            if let Some(id) = maps::map_id(&stack) {
+                use horizon_client::first_person::{MapHold, one_handed_map_pose};
+                match MapHold::of(hand, off_hand_empty) {
+                    MapHold::TwoHanded => self.two_handed_map_geometry(
+                        to_world,
+                        attack,
+                        inverse_height,
+                        id,
+                        packed,
+                        &mut out,
+                    ),
+                    MapHold::OneHanded => self.held_map(
+                        to_world * one_handed_map_pose(left, inverse_height, attack),
+                        id,
+                        packed,
+                        &mut out,
+                    ),
+                }
+                continue;
+            }
            let mut owner = self.player_owner(Some(&stack));
            // The other hand may hold an equal stack: only the used
            // hand's item is in use, only the main hand's selected.
@@ -9036,21 +9091,11 @@ impl Game<'_> {
        // Options.biomeBlendRadius, ambientOcclusion and cutoutLeaves:
        // LevelExtractor.allChanged when they change.
        let (s, st) = (&self.settings, &self.streaming);
-        let remesh = (
-            s.biome_blend,
-            s.smooth_lighting,
-            s.cutout_leaves,
-            s.horizon.cull_leaves,
-        ) != (
-            st.biome_blend,
-            st.smooth_lighting,
-            st.cutout_leaves,
-            st.cull_leaves,
-        );
+        let remesh = (s.biome_blend, s.smooth_lighting, s.cutout_leaves)
+            != (st.biome_blend, st.smooth_lighting, st.cutout_leaves);
        self.streaming.biome_blend = self.settings.biome_blend;
        self.streaming.smooth_lighting = self.settings.smooth_lighting;
        self.streaming.cutout_leaves = self.settings.cutout_leaves;
-        self.streaming.cull_leaves = self.settings.horizon.cull_leaves;
        if remesh {
            self.all_sections_changed();
        }
@@ -9767,7 +9812,6 @@ impl Game<'_> {
            }
            return Ok(false);
        }
-        self.poll_shader_pack();
        let Some(size) = self
            .renderer
            .as_ref()
@@ -9980,18 +10024,6 @@ impl Game<'_> {
            self.dragon_fireball_geometry(camera, alpha, &mut dragon);
            entities.extend(dragon);
        }
-        // A Java pack's `clouds` replaces the cloud option (`renderClouds`:
-        // "false", "fast", "true"), as Iris overrides `getCloudsType`.
-        let clouds_mode = {
-            use horizon_shaderpack::properties::CloudSetting;
-            match self.java_sky().and_then(|(_, sky)| sky.clouds) {
-                Some(CloudSetting::Off) => "false",
-                Some(CloudSetting::Fast) => "fast",
-                Some(CloudSetting::Fancy) => "true",
-                None => self.settings.clouds.as_str(),
-            }
-            .to_owned()
-        };
        let (celestial, stars) = if title {
            (Vec::new(), None)
        } else if self.dim == Dim::Overworld
@@ -10035,7 +10067,6 @@ impl Game<'_> {
        let frame = Frame {
            weather: &weather,
            weather_time: horizon_client::weather::Time::new(self.world.game_time, alpha as f32),
-            shader: self.shader_inputs(camera, alpha as f32),
            nether_lighting: self.dim == Dim::Nether,
            camera,
            yaw,
@@ -10083,7 +10114,7 @@ impl Game<'_> {
            hud: &hud,
            clouds: (!title
                && self.dim == Dim::Overworld
-                && horizon_client::clouds::visible(&clouds_mode, sky.cloud_color[3]))
+                && horizon_client::clouds::visible(&self.settings.clouds, sky.cloud_color[3]))
            .then(|| self.gui.atlas.sprites.get("horizon/white"))
            .flatten()
            .map(|white| horizon_client::clouds::Input {
@@ -10093,7 +10124,7 @@ impl Game<'_> {
                time: self.world.game_time,
                partial_tick: alpha,
                range: self.settings.cloud_range,
-                fast: clouds_mode == "fast",
+                fast: self.settings.clouds == "fast",
                color: sky.cloud_color,
            }),
            entities: &entities,
@@ -10315,6 +10346,11 @@ impl Game<'_> {
                if (self.screen == Screen::Inventory
                    || (self.screen == Screen::Creative && !self.creative_screen.tab().search))
                    && self.inventory_hotkey(key) => {}
+            // The search tab's number keys (scripted presses; the window's
+            // keys reach search_tab_hotbar_key before the search box).
+            _ if self.screen == Screen::Creative
+                && self.creative_screen.tab().search
+                && self.search_tab_hotbar_key(key) => {}
            KeyCode::KeyT if self.screen == Screen::Inventory => self.recipe_focus_search(),
            KeyCode::KeyT if self.screen == Screen::Playing => self.open_chat(""),
            // key.advancements.
@@ -10806,9 +10842,6 @@ impl ApplicationHandler for Game<'_> {
                WindowEvent::CloseRequested => {
                    self.pending_save.as_mut().unwrap().quit = true;
                }
-                WindowEvent::DroppedFile(path) => {
-                    self.drop_shader_pack(&path);
-                }
                WindowEvent::Focused(focused) => {
                    self.focused = focused;
                    if !focused {
@@ -10963,6 +10996,13 @@ impl ApplicationHandler for Game<'_> {
                        self.advancements_scroll(scaled(raw_x) as f32, d);
                    }
                }
+                WindowEvent::MouseInput { state, button, .. }
+                    if self.server_packs.prompt.is_some() =>
+                {
+                    if state == ElementState::Pressed && button == MouseButton::Left {
+                        self.pack_prompt_click()?;
+                    }
+                }
                WindowEvent::MouseInput { .. } if self.screen == Screen::Win => {}
                WindowEvent::MouseInput { state, button, .. } if self.screen == Screen::Options => {
                    if self.options_waiting_for_key() && state == ElementState::Pressed {
@@ -11162,6 +11202,14 @@ impl ApplicationHandler for Game<'_> {
                        _ => {}
                    }
                }
+                // ConfirmScreen.keyPressed: Escape answers no.
+                WindowEvent::KeyboardInput { event, .. } if self.server_packs.prompt.is_some() => {
+                    if event.state == ElementState::Pressed
+                        && event.physical_key == PhysicalKey::Code(KeyCode::Escape)
+                    {
+                        self.answer_pack_prompt(false)?;
+                    }
+                }
                WindowEvent::KeyboardInput { event, .. }
                    if self.screen == Screen::Chat && self.title.is_none() =>
                {
@@ -11186,7 +11234,11 @@ impl ApplicationHandler for Game<'_> {
                        && event.state == ElementState::Pressed
                        && !matches!(event.physical_key, PhysicalKey::Code(KeyCode::Escape)) =>
                {
-                    if let Some(shortcut) = self.edit_shortcut(&event) {
+                    if let PhysicalKey::Code(key) = event.physical_key
+                        && self.search_tab_hotbar_key(key)
+                    {
+                        // The hovered slot took the key (`ignoreTextInput`).
+                    } else if let Some(shortcut) = self.edit_shortcut(&event) {
                        self.creative_search_shortcut(shortcut);
                    } else {
                        let backspace = event.physical_key == PhysicalKey::Code(KeyCode::Backspace);
@@ -11536,6 +11588,7 @@ impl ApplicationHandler for Game<'_> {
            event_loop.exit();
            return;
        }
+        self.tick_server_packs();
        self.poll_control(event_loop);
        if self.pending_save.is_some() {
            return;
@@ -11630,6 +11683,7 @@ impl<'a> Game<'a> {
            pending_entry: None,
            world_loader: None,
            pending_pack_reload: false,
+            server_packs: Default::default(),
            world_renderer_ready: false,
            collision: res.collision(),
            motion: res.motion(),
@@ -11687,7 +11741,6 @@ impl<'a> Game<'a> {
            focused: true,
            modifiers: winit::keyboard::ModifiersState::empty(),
            fullscreen: horizon_client::window::FullscreenState::new(false),
-            shader_packs: Default::default(),
            mouse: MouseLook::default(),
            agent_pointer: false,
            smooth_camera: false,
@@ -11847,6 +11900,7 @@ impl<'a> Game<'a> {
            recipe_ui: Default::default(),
            mount_menu: Default::default(),
            hook: None,
+            remote_hooks: Vec::new(),
            tridents: Vec::new(),
            rockets: Vec::new(),
            ominous_spawners: Vec::new(),
@@ -12124,6 +12178,33 @@ impl Game<'_> {
    }
 }

+/// `key.hotbar.1` to `key.hotbar.9` in a menu.
+const HOTBAR_DIGITS: [KeyCode; 9] = [
+    KeyCode::Digit1,
+    KeyCode::Digit2,
+    KeyCode::Digit3,
+    KeyCode::Digit4,
+    KeyCode::Digit5,
+    KeyCode::Digit6,
+    KeyCode::Digit7,
+    KeyCode::Digit8,
+    KeyCode::Digit9,
+];
+/// The other keys `InputConstants.Key.getNumericKeyValue` gives a digit.
+const NUMERIC_KEYS: [KeyCode; 11] = [
+    KeyCode::Digit0,
+    KeyCode::Numpad0,
+    KeyCode::Numpad1,
+    KeyCode::Numpad2,
+    KeyCode::Numpad3,
+    KeyCode::Numpad4,
+    KeyCode::Numpad5,
+    KeyCode::Numpad6,
+    KeyCode::Numpad7,
+    KeyCode::Numpad8,
+    KeyCode::Numpad9,
+];
+
 const STAGES: u32 = 10;
 const STAGE_LINES: [&str; 10] = [
    "Loading menu",
@@ -12618,7 +12699,6 @@ fn loading_frame(hud: &HudBatch) -> Frame<'_> {
        night_vision: 0.0,
        block_flicker: 0.0,
        menu_blur: None,
-        shader: Default::default(),
    }
 }

@@ -13192,7 +13272,7 @@ pub fn run() -> Result<()> {
        return run_loading(options, early_settings, vanilla_root, None, started);
    }
    let mut pack_error = None;
-    options.resources = packs::startup_root(&vanilla_root, &early_settings.resource_packs)
+    options.resources = packs::startup_root(&vanilla_root, &early_settings.resource_packs, &[])
        .unwrap_or_else(|e| {
            log::warn!("Horizon: resource packs not applied: {e}");
            pack_error = Some(e.to_string());
@@ -9,6 +9,10 @@ use horizon_client::{
    block_entity_anim::Ticker,
    chunk::{MIN_Y, SECTIONS},
    items::ItemStack,
+    mobs::{
+        Species,
+        render::{PROFESSIONS, VILLAGER_TYPES},
+    },
    widgets,
 };
 use horizon_core::geometry::Vec3;
@@ -335,6 +339,12 @@ impl Game<'_> {
            Some(Ticker::Shulker { .. }) => v["lid"] = json!(self.block_anim(pos, 1.0).shulker.0),
            _ => {}
        }
+        // The lines of a sign, as this client has them.
+        if let Some(horizon_client::containers::BlockEntity::Sign(sign)) =
+            self.world.block_entities.get(&(pos[0], pos[1], pos[2]))
+        {
+            v["sign"] = json!({ "front": sign.front.lines, "back": sign.back.lines });
+        }
        v
    }
    pub(super) fn stack_value(&self, s: &ItemStack) -> Value {
@@ -457,10 +467,13 @@ impl Game<'_> {
                "velocity": [p.velocity.x, p.velocity.y, p.velocity.z],
                "on_ground": p.ground.on_ground,
                "flying": p.flying,
+                "fall_flying": p.fall_flying,
                "sneaking": self.keys.contains(&KeyCode::ShiftLeft),
                "sprinting": self.keys.contains(&KeyCode::ControlLeft),
                "health": p.health.health(),
                "absorption": p.health.absorption(),
+                // The hurt animation's ticks left (the camera's hurt tilt).
+                "hurt_time": p.health.hurt_animation_time,
                "air": p.air,
                "food": p.health.food.food,
                "saturation": p.health.food.saturation,
@@ -585,10 +598,20 @@ impl Game<'_> {
            }
        };
        for m in self.mobs.iter().filter(|m| m.alive()) {
+            let mut v = json!({ "id": m.id, "kind": "mob", "health": m.health, "baby": m.is_baby(), "hurt_time": m.hurt_time });
+            // VillagerData as this game knows it: on a client, what the
+            // server's synched data says.
+            if matches!(m.species(), Species::Villager | Species::ZombieVillager) {
+                v["villager"] = json!({
+                    "type": VILLAGER_TYPES[m.extra.variant as usize % VILLAGER_TYPES.len()],
+                    "profession": PROFESSIONS[m.extra.variant2 as usize % PROFESSIONS.len()],
+                    "level": m.extra.variant3,
+                });
+            }
            push(
                [m.position.x, m.position.y, m.position.z],
                m.kind.id.as_ref(),
-                json!({ "id": m.id, "kind": "mob", "health": m.health, "baby": m.is_baby(), "hurt_time": m.hurt_time }),
+                v,
            );
        }
        for item in &self.dropped {
@@ -59,6 +59,30 @@ impl Game<'_> {
    }
    /// Block commands; None when `words[0]` is not one of them.
    pub(super) fn block_command(&mut self, words: &[&str]) -> Result<Option<Value>> {
+        let ours = matches!(
+            words.first(),
+            Some(&("setblock" | "fill" | "getblock" | "container"))
+        );
+        // Single player on its server thread: the world is the server's, so
+        // the command runs there, in the owner's level, and the client hears
+        // of it like any change.
+        if ours && let Some(server) = &self.integrated {
+            let owned: Vec<String> = words.iter().map(|w| (*w).to_owned()).collect();
+            return server
+                .call(move |g| {
+                    let words: Vec<&str> = owned.iter().map(String::as_str).collect();
+                    g.in_owner_level(|g| g.block_command(&words).map_err(|e| e.to_string()))
+                })
+                .ok_or("the integrated server stopped")?
+                .map_err(Into::into);
+        }
+        // Another server's world changes only through its own commands, which
+        // it checks as the player's; `getblock` and `container` read what this
+        // client has of it.
+        if self.remote.is_some() && matches!(words.first(), Some(&("setblock" | "fill"))) {
+            self.send_chat(&format!("/{}", words.join(" ")));
+            return Ok(Some(json!({ "ok": true, "sent": true })));
+        }
        let int = |i: usize| -> Result<i32> {
            Ok(words
                .get(i)
@@ -0,0 +1,453 @@
+//! Boats and the entities around them: what a boat runs into
+//! (`AbstractBoat.canVehicleCollide`), the pushes between a boat and what
+//! touches it (`AbstractBoat.push`, `LivingEntity.pushEntities`), the mobs
+//! it picks up (the end of `AbstractBoat.tick`), where they sit
+//! (`positionRider`, `clampRotation`) and how they get out.
+//! Saving them under the boat's `Passengers` lives in `persist.rs`.
+use super::{Game, boats::Boat, lan_mobs::guest_bounds};
+use horizon_client::{
+    camera::wrap_degrees,
+    mobs::{Mob, Species, Who, drops::is_animal, equine, riders},
+    scoreboard::pushable_by,
+};
+use horizon_core::geometry::{Aabb, Vec3};
+
+/// `Entity.boardingCooldown` once a mob leaves its boat.
+const BOARDING_COOLDOWN: i32 = 60;
+/// `Player.DEFAULT_VEHICLE_ATTACHMENT`: how far below the seat a player's
+/// feet are.
+const PLAYER_RIDING_OFFSET: f64 = 0.6;
+
+/// `Entity.isVehicle`: a player or a mob rides it.
+fn carries(m: &Mob) -> bool {
+    m.rider.is_some() || m.extra.rider.is_some()
+}
+/// `isPushable`, as `pushableBy` and `canVehicleCollide` ask it:
+/// `Mob::pushable` plus the shulkers it leaves out (they take no push, but
+/// count), less a ridden horse (`AbstractHorse.isPushable`).
+fn pushable(m: &Mob) -> bool {
+    !m.removed
+        && (m.pushable() || m.species() == Species::Shulker && m.alive())
+        && !(equine::is_equine(m.species()) && carries(m))
+}
+/// Whether `Entity.push` moves the mob: it is pushable and carries no one.
+fn moved_by_push(m: &Mob) -> bool {
+    !m.removed && m.pushable() && !carries(m)
+}
+/// `Entity.push(Entity)`: the push `other` gets from `this` (which takes the
+/// opposite one), or None when they stand on nearly the same spot.
+pub(super) fn push_impulse(this: Vec3, other: Vec3) -> Option<Vec3> {
+    let (mut xa, mut za) = (other.x - this.x, other.z - this.z);
+    let mut dd = xa.abs().max(za.abs());
+    if dd < f64::from(0.01_f32) {
+        return None;
+    }
+    dd = dd.sqrt();
+    xa /= dd;
+    za /= dd;
+    let pow = (1.0 / dd).min(1.0);
+    let k = f64::from(0.05_f32);
+    Some(Vec3::new(xa * pow * k, 0.0, za * pow * k))
+}
+/// `AbstractBoat.push`: another boat is pushed while it is lower than this
+/// boat's top, anything else while its feet are no higher than the boat's.
+pub(super) fn boat_pushes(boat: Aabb, other: Aabb, other_is_boat: bool) -> bool {
+    if other_is_boat {
+        other.min_position().y < boat.max_position().y
+    } else {
+        other.min_position().y <= boat.min_position().y
+    }
+}
+
+impl Game<'_> {
+    /// The players in boat `id`: the window's player (or the server player
+    /// acting as it) and the server's other players.
+    pub(super) fn boat_players(&self, id: u32) -> usize {
+        let guests = self.lan.as_ref().map_or(0, |h| {
+            h.hub
+                .guests
+                .iter()
+                .filter(|g| Some(g.conn) != self.lan_acting && g.vehicle == Some(id))
+                .count()
+        });
+        usize::from(self.riding == Some(id)) + guests
+    }
+    /// The mobs in boat `id`, in their seat order after the players
+    /// (`Entity.addPassenger` puts a player first).
+    pub(super) fn boat_mobs(&self, id: u32) -> Vec<usize> {
+        (0..self.mobs.len())
+            .filter(|&j| {
+                let m = &self.mobs[j];
+                m.extra.mount == Some(id) && !m.removed && m.alive()
+            })
+            .collect()
+    }
+    /// `getPassengers().size()` of boat `id`.
+    pub(super) fn boat_passengers(&self, id: u32) -> usize {
+        self.boat_players(id) + self.boat_mobs(id).len()
+    }
+    /// `AbstractBoat.canAddPassenger`: a seat is free and the boat is not
+    /// under water.
+    pub(super) fn boat_has_room(&self, i: usize) -> bool {
+        let b = &self.boats[i];
+        self.boat_passengers(b.id) < b.max_passengers() && !b.under_water()
+    }
+    /// Where the player in boat `i` sits: in the middle alone, in front of a
+    /// mob.
+    pub(super) fn player_boat_seat(&self, i: usize) -> Vec3 {
+        let b = &self.boats[i];
+        let count = self.boat_players(b.id).max(1) + self.boat_mobs(b.id).len();
+        b.seat(0, count, false, PLAYER_RIDING_OFFSET, false)
+    }
+    /// `getRootVehicle` of mob `j`: the mob or boat at the bottom of what it
+    /// rides, None when it rides nothing.
+    fn mob_root_vehicle(&self, mut j: usize) -> Option<u32> {
+        let mut root = None;
+        for _ in 0..8 {
+            let Some(v) = self.mobs[j].extra.mount else {
+                break;
+            };
+            root = Some(v);
+            match self.mobs.iter().position(|m| m.id == v) {
+                Some(k) => j = k,
+                None => break,
+            }
+        }
+        root
+    }
+    /// The players outside boat `id` that push and block it (living, not
+    /// spectators), with the window player's team.
+    fn players_outside(&self, id: u32) -> Vec<(Aabb, bool)> {
+        let mut out = Vec::new();
+        if let Some(p) = self.player.as_ref()
+            && self.riding != Some(id)
+            && !self.spectator()
+            && !p.health.dead_or_dying()
+        {
+            out.push((p.bounds(), true));
+        }
+        if let Some(host) = self.lan.as_ref() {
+            for g in host.hub.guests.iter().filter(|g| {
+                Some(g.conn) != self.lan_acting
+                    && host.hub.here(g)
+                    && g.loaded
+                    && !g.dead
+                    && !g.spectator()
+                    && g.vehicle != Some(id)
+            }) {
+                out.push((guest_bounds(g), false));
+            }
+        }
+        out
+    }
+    /// `getEntityCollisions` of boat `id` within `area`, with
+    /// `AbstractBoat.canVehicleCollide`: the other boats, minecarts,
+    /// shulkers and pushable mobs and players, but not its own passengers.
+    pub(super) fn boat_obstacles(&self, id: u32, area: Aabb) -> Vec<Aabb> {
+        let mut out: Vec<Aabb> = (0..self.mobs.len())
+            .filter(|&j| {
+                let m = &self.mobs[j];
+                pushable(m)
+                    && m.bounds().intersects(area)
+                    && (m.extra.mount.is_none() || self.mob_root_vehicle(j) != Some(id))
+            })
+            .map(|j| self.mobs[j].bounds())
+            .collect();
+        out.extend(
+            self.boats
+                .iter()
+                .filter(|b| b.id != id)
+                .map(Boat::bounds)
+                .chain(self.carts.iter().map(|c| c.bounds()))
+                .chain(self.players_outside(id).into_iter().map(|(bb, _)| bb))
+                .filter(|bb| bb.intersects(area)),
+        );
+        out
+    }
+    /// What boat `b` may run into this tick.
+    pub(super) fn boat_move_obstacles(&self, b: &Boat) -> Vec<Aabb> {
+        let reach = b.velocity.length() + 1.0;
+        self.boat_obstacles(b.id, b.bounds().inflate(Vec3::new(reach, reach, reach)))
+    }
+    /// `noEntityCollision(boat, box)` for a new boat (`BoatItem.use`).
+    pub(super) fn boat_entity_collision(&self, bb: Aabb) -> bool {
+        // EntityGetter.getEntityCollisions: the box grown by 1e-7.
+        let area = bb.inflate(Vec3::new(1.0e-7, 1.0e-7, 1.0e-7));
+        !self.boat_obstacles(u32::MAX, area).is_empty()
+    }
+
+    /// The end of `AbstractBoat.tick` on the server for boat `i`: each
+    /// entity it touches gets in (a mob, while no player steers) or is
+    /// pushed apart from it, and `LivingEntity.pushEntities` of each mob and
+    /// player touching it pushes the two apart once more. Only the window's
+    /// own player is moved here: a server's players are pushed by their
+    /// clients, which tick the boats near them (`remote_pushes`).
+    pub(super) fn boat_contacts(&mut self, i: usize) {
+        let (id, bb, max) = {
+            let b = &self.boats[i];
+            (b.id, b.bounds(), b.max_passengers())
+        };
+        let area = bb.inflate(Vec3::new(
+            f64::from(0.2_f32),
+            f64::from(-0.01_f32),
+            f64::from(0.2_f32),
+        ));
+        let mut count = self.boat_passengers(id);
+        // getControllingPassenger is a player: one rides it (players sit first).
+        let pick_up = self.boat_players(id) == 0;
+        // canAddPassenger, which startRiding asks after the checks below.
+        let room = !self.boats[i].under_water();
+        // (mob, touched by the boat's sweep, its own pushEntities reaches the boat)
+        let teams = self.mob_teams();
+        let mobs: Vec<(usize, bool, bool)> = (0..self.mobs.len())
+            .filter_map(|j| {
+                let m = &self.mobs[j];
+                if !pushable(m) || m.extra.mount.is_some() && self.mob_root_vehicle(j) == Some(id) {
+                    return None;
+                }
+                let mb = m.bounds();
+                let team = teams.of(Who::Mob(m.id));
+                let touched = mb.intersects(area) && pushable_by(None, team, true);
+                // Bats push nothing (Bat.pushEntities).
+                let pushes = m.species() != Species::Bat
+                    && mb.intersects(bb)
+                    && pushable_by(team, None, true);
+                (touched || pushes).then_some((j, touched, pushes))
+            })
+            .collect();
+        let player_team = teams.of(Who::Player);
+        let players: Vec<(Aabb, bool, bool, bool)> = self
+            .players_outside(id)
+            .into_iter()
+            .map(|(pb, own)| {
+                let team = if own { player_team } else { None };
+                (
+                    pb,
+                    own,
+                    pb.intersects(area) && pushable_by(None, team, true),
+                    pb.intersects(bb) && pushable_by(team, None, true),
+                )
+            })
+            .collect();
+        drop(teams);
+        for (j, touched, pushes) in mobs {
+            if touched {
+                let m = &self.mobs[j];
+                let boards = pick_up
+                    && count < max
+                    && m.extra.mount.is_none()
+                    && m.width() < super::boats::WIDTH as f32
+                    && !self
+                        .res
+                        .mob_data()
+                        .entity_has("minecraft:cannot_be_pushed_onto_boats", &m.kind.id);
+                if boards {
+                    // startRiding fails quietly (no push) while the mob's
+                    // boarding cooldown runs (Entity.canRide) or the boat
+                    // is under water.
+                    if room && m.extra.boarding_cooldown <= 0 {
+                        let m = &mut self.mobs[j];
+                        m.extra.mount = Some(id);
+                        m.extra.passenger = true;
+                        m.ai.nav.stop();
+                        let mob = m.id;
+                        count += 1;
+                        // Mob.startRiding drops its lead.
+                        self.break_leash(mob, true, false);
+                    }
+                    continue;
+                }
+                self.boat_push_mob(i, j, count);
+            }
+            if pushes {
+                self.boat_push_mob(i, j, count);
+            }
+        }
+        for (pb, own, touched, pushes) in players {
+            let Some(v) = push_impulse(self.boats[i].position, pb.center())
+                .filter(|_| boat_pushes(bb, pb, false))
+            else {
+                continue;
+            };
+            for _ in 0..usize::from(touched) + usize::from(pushes) {
+                if count == 0 {
+                    let b = &mut self.boats[i];
+                    b.velocity = b.velocity.subtract(v);
+                }
+                if own && let Some(p) = self.player.as_mut() {
+                    p.velocity = p.velocity.add_vector(v);
+                }
+            }
+        }
+        for k in 0..self.boats.len() {
+            let ob = self.boats[k].bounds();
+            if k == i || !ob.intersects(area) || !boat_pushes(bb, ob, true) {
+                continue;
+            }
+            let Some(v) = push_impulse(self.boats[i].position, self.boats[k].position) else {
+                continue;
+            };
+            if count == 0 {
+                self.boats[i].velocity = self.boats[i].velocity.subtract(v);
+            }
+            if self.boat_passengers(self.boats[k].id) == 0 {
+                self.boats[k].velocity = self.boats[k].velocity.add_vector(v);
+            }
+        }
+        let guest_carts = self.guest_vehicles();
+        for c in 0..self.carts.len() {
+            let cb = self.carts[c].bounds();
+            if !cb.intersects(area) || !boat_pushes(bb, cb, false) {
+                continue;
+            }
+            let Some(v) = push_impulse(self.boats[i].position, self.carts[c].position) else {
+                continue;
+            };
+            if count == 0 {
+                self.boats[i].velocity = self.boats[i].velocity.subtract(v);
+            }
+            let cid = self.carts[c].id;
+            let ridden = self.riding == Some(cid)
+                || guest_carts.contains(&cid)
+                || self.mobs.iter().any(|m| m.extra.mount == Some(cid));
+            if !ridden {
+                self.carts[c].velocity = self.carts[c].velocity.add_vector(v);
+            }
+        }
+    }
+    /// `AbstractBoat.push(mob)` from boat `i`, which has `count` passengers.
+    fn boat_push_mob(&mut self, i: usize, j: usize, count: usize) {
+        let (b, m) = (&self.boats[i], &self.mobs[j]);
+        if !boat_pushes(b.bounds(), m.bounds(), false) {
+            return;
+        }
+        let Some(v) = push_impulse(b.position, m.position) else {
+            return;
+        };
+        if count == 0 {
+            let b = &mut self.boats[i];
+            b.velocity = b.velocity.subtract(v);
+        }
+        let m = &mut self.mobs[j];
+        if moved_by_push(m) {
+            m.velocity = m.velocity.add_vector(v);
+            m.needs_sync = true;
+        }
+    }
+
+    /// `positionRider` and `clampRotation` for the mobs in boats: each sits
+    /// in its seat facing the way the boat does, an animal in a full boat
+    /// sideways, its head kept within its reach of its body.
+    pub(super) fn seat_boat_mobs(&mut self) {
+        for i in 0..self.boats.len() {
+            let id = self.boats[i].id;
+            let mobs = self.boat_mobs(id);
+            if mobs.is_empty() {
+                continue;
+            }
+            let players = self.boat_players(id);
+            let count = players + mobs.len();
+            let b = &self.boats[i];
+            let full = count == b.max_passengers();
+            let delta = b.delta_rotation;
+            let seats: Vec<_> = mobs
+                .iter()
+                .enumerate()
+                .map(|(n, &j)| {
+                    let m = &self.mobs[j];
+                    let animal = is_animal(m.species());
+                    // Another player, on a server's client.
+                    let offset = if &*m.kind.id == "minecraft:player" {
+                        PLAYER_RIDING_OFFSET
+                    } else {
+                        riders::vehicle_attachment(m)
+                    };
+                    let index = players + n;
+                    // calculatePassengerBodyYRot.
+                    let turn = match (animal && full, m.id.is_multiple_of(2)) {
+                        (false, _) => 0.0,
+                        (true, true) => 90.0,
+                        (true, false) => 270.0,
+                    };
+                    let turns = !self
+                        .res
+                        .mob_data()
+                        .entity_has("minecraft:can_turn_in_boats", &m.kind.id);
+                    (
+                        j,
+                        b.seat(index, count, animal, offset, false),
+                        b.seat(index, count, animal, offset, true),
+                        turns.then_some((b.yaw + turn, b.previous_yaw + turn)),
+                    )
+                })
+                .collect();
+            for (j, at, previous, facing) in seats {
+                let m = &mut self.mobs[j];
+                m.position = at;
+                m.previous = previous;
+                m.velocity = Vec3::ZERO;
+                m.fall_distance = 0.0;
+                m.on_ground = false;
+                m.extra.passenger = true;
+                m.ai.nav.stop();
+                let Some((body, previous_body)) = facing else {
+                    continue;
+                };
+                m.head_yaw += delta;
+                m.body_yaw = body;
+                m.previous_body_yaw = previous_body;
+                m.yaw = body;
+                m.previous_yaw = previous_body;
+                // Mob.clampHeadRotationToBody.
+                let limit = m.kind.max_head_y_rot;
+                let d = wrap_degrees(body - m.head_yaw);
+                m.head_yaw += d - d.clamp(-limit, limit);
+            }
+        }
+    }
+    /// `ejectPassengers` for the mobs in boat `i`: each gets out where
+    /// `getDismountLocationForPassenger` puts it (beside the boat when it
+    /// broke: `LivingEntity.dismountVehicle`) and can't board for a while.
+    pub(super) fn eject_boat_mobs(&mut self, i: usize, broken: bool) {
+        let b = &self.boats[i];
+        let (id, y) = (b.id, b.position.y);
+        for j in self.boat_mobs(id) {
+            let m = &self.mobs[j];
+            let at = if broken {
+                Vec3::new(m.position.x, m.position.y.max(y), m.position.z)
+            } else {
+                self.boat_dismount_target(i, f64::from(m.width()), m.yaw)
+            };
+            let m = &mut self.mobs[j];
+            m.extra.mount = None;
+            m.extra.passenger = false;
+            m.extra.boarding_cooldown = BOARDING_COOLDOWN;
+            m.position = at;
+            m.previous = at;
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn push_is_capped_and_scaled() {
+        // One block apart on x: the full 0.05 along x.
+        let v = push_impulse(Vec3::ZERO, Vec3::new(1.0, 0.0, 0.0)).unwrap();
+        assert!((v.x - f64::from(0.05_f32)).abs() < 1e-12 && v.z == 0.0);
+        // Almost on the same spot: no push.
+        assert!(push_impulse(Vec3::ZERO, Vec3::new(0.005, 0.0, 0.0)).is_none());
+    }
+
+    #[test]
+    fn boats_push_by_height() {
+        let boat = Aabb::new(Vec3::new(0.0, 64.0, 0.0), Vec3::new(1.0, 64.5625, 1.0));
+        let at = |y: f64| Aabb::new(Vec3::new(0.0, y, 0.0), Vec3::new(1.0, y + 1.0, 1.0));
+        assert!(boat_pushes(boat, at(64.0), false));
+        assert!(!boat_pushes(boat, at(64.1), false));
+        assert!(boat_pushes(boat, at(64.5), true));
+        assert!(!boat_pushes(boat, at(64.5625), true));
+    }
+}
@@ -5,10 +5,10 @@
 use super::{Game, Keys, entity_culling::at, view_vector};
 use horizon_client::{
    blocks::Fluid,
-    collisions::SceneCollisions,
+    collisions::{EntityCollisions, SceneCollisions},
    items::ItemStack,
    mesher::Vertex,
-    mobs::{Part, anim::Poses},
+    mobs::{Part, anim::Poses, riders},
 };
 use horizon_core::{
    geometry::{Aabb, Vec3},
@@ -54,10 +54,8 @@ pub(super) struct Boat {
 }
 /// `ChestBoat.CONTAINER_SIZE`.
 pub(super) const CHEST_SLOTS: usize = 27;
-const WIDTH: f64 = 1.375;
+pub(super) const WIDTH: f64 = 1.375;
 const HEIGHT: f64 = 0.5625;
-/// Player.DEFAULT_VEHICLE_ATTACHMENT minus the boat's passenger attachment.
-pub(super) const SEAT: f64 = 0.1875 - 0.6;
 impl Boat {
    pub fn new(id: u32, wood: Arc<str>, position: Vec3, yaw: f32) -> Self {
        Self {
@@ -98,6 +96,54 @@ impl Boat {
            Vec3::new(p.x + w, p.y + HEIGHT, p.z + w),
        )
    }
+    /// `isUnderWater`; it stands in for `canAddPassenger`'s
+    /// `isEyeInFluid(WATER)` too.
+    pub fn under_water(&self) -> bool {
+        matches!(self.status, Status::UnderWater | Status::UnderFlowingWater)
+    }
+    /// `getMaxPassengers`: two, one beside a chest.
+    pub fn max_passengers(&self) -> usize {
+        if self.chest { 1 } else { 2 }
+    }
+    /// `rideHeight`: a third of a boat's height, 8/9 of a raft's.
+    fn ride_height(&self) -> f64 {
+        let height = HEIGHT as f32;
+        f64::from(if &*self.wood == "bamboo" {
+            height * 0.888_888_9
+        } else {
+            height / 3.0
+        })
+    }
+    /// Where the passenger at `index` of `count` stands, at the boat's current
+    /// (or, with `previous`, last) place: `getPassengerAttachmentPoint`
+    /// turned with the boat, less the passenger's `rider_offset`.
+    pub fn seat(
+        &self,
+        index: usize,
+        count: usize,
+        animal: bool,
+        rider_offset: f64,
+        previous: bool,
+    ) -> Vec3 {
+        let mut z = if self.chest { 0.15f32 } else { 0.0 };
+        if count > 1 {
+            z = if index == 0 { 0.2 } else { -0.6 };
+            if animal {
+                z += 0.2;
+            }
+        }
+        let (at, yaw) = if previous {
+            (self.previous, self.previous_yaw)
+        } else {
+            (self.position, self.yaw)
+        };
+        riders::seat(
+            [0.0, self.ride_height(), f64::from(z)],
+            rider_offset,
+            at,
+            yaw,
+        )
+    }
    /// `getRowingTime`.
    pub fn rowing_time(&self, side: usize, a: f32) -> f32 {
        if self.paddling[side] {
@@ -183,13 +229,18 @@ impl BoatModels {
 }
 impl Game<'_> {
    fn fluid_height(&self, x: i32, y: i32, z: i32) -> Option<(f32, bool)> {
+        self.fluid_height_of(x, y, z, Some(Fluid::Water))
+    }
+    /// `FluidState.getHeight` and whether it is a source, for `fluid` or,
+    /// with `None`, any fluid (`ClipContext.Fluid.ANY`).
+    fn fluid_height_of(&self, x: i32, y: i32, z: i32, fluid: Option<Fluid>) -> Option<(f32, bool)> {
        let f = self.res.facts().get(self.world.block(x, y, z));
-        if f.fluid != Fluid::Water {
+        if f.fluid == Fluid::None || fluid.is_some_and(|want| f.fluid != want) {
            return None;
        }
        let above = self.res.facts().get(self.world.block(x, y + 1, z));
        // FluidState.getHeight: 1 under the same fluid, else amount / 9.
-        let height = if above.fluid == Fluid::Water {
+        let height = if above.fluid == f.fluid {
            1.0
        } else {
            f32::from(f.fluid_level) / 9.0
@@ -315,6 +366,7 @@ impl Game<'_> {
        let mut vspeed = -0.04;
        let mut buoyancy = 0.0;
        let inv_friction: f32;
+        let obstacles = self.boat_move_obstacles(&b);
        let mut scene = SceneCollisions {
            world: &self.world,
            binding: self.collision,
@@ -396,6 +448,11 @@ impl Game<'_> {
            b.paddling = [right && !left || up, left && !right || up];
        }
        // Entity.move: collisions zero the blocked components.
+        let mut scene = EntityCollisions {
+            blocks: scene,
+            entities: &obstacles,
+            border: None,
+        };
        if let Ok(moved) = scene.resolve(b.bounds(), b.velocity, 0.0, b.on_ground) {
            b.position = Vec3::new(
                b.position.x + moved.x,
@@ -461,6 +518,72 @@ impl Game<'_> {
            let b = self.boats[i].clone();
            self.boats[i] = self.tick_boat(b, false);
        }
+        // AbstractBoat.tick's applyEffectsFromBlocks, on the server for every
+        // boat, the client-driven ones too.
+        let mut i = 0;
+        while i < self.boats.len() {
+            let p = self.boats[i].position;
+            let skip = Some(self.boats[i].id) == self.riding
+                || !ticking(p.x.floor() as i32, p.z.floor() as i32);
+            if skip || !self.boat_lava_tick(i) {
+                i += 1;
+            }
+        }
+        // The rest of AbstractBoat.tick on the server, for every boat: the
+        // passengers of one under water too long get out, and it picks up or
+        // pushes what it touches.
+        for i in 0..self.boats.len() {
+            let p = self.boats[i].position;
+            if !ticking(p.x.floor() as i32, p.z.floor() as i32) {
+                continue;
+            }
+            if self.boats[i].out_of_control >= 60.0 {
+                self.eject_boat_mobs(i, false);
+            }
+            self.boat_contacts(i);
+        }
+    }
+    /// `LavaFluid.entityInside` (`lavaHurt`) from the two
+    /// `applyEffectsFromBlocks` calls in `AbstractBoat.tick`: twice 40
+    /// damage, so lava breaks a boat on its first tick inside, and the fire
+    /// `lavaIgnite` lights never gets to burn it. True when the boat broke.
+    fn boat_lava_tick(&mut self, i: usize) -> bool {
+        if !self.in_lava(self.boats[i].bounds()) {
+            return false;
+        }
+        for _ in 0..2 {
+            let p = self.boats[i].position;
+            let broke = self.hurt_boat(i, 4.0, false);
+            self.lava_hurt_sound([p.x, p.y, p.z]);
+            if broke {
+                return true;
+            }
+        }
+        false
+    }
+    /// `Entity.lavaHurt`'s sound once the hurt went through.
+    pub(super) fn lava_hurt_sound(&mut self, at: [f64; 3]) {
+        let pitch = 2.0 + self.world.random.next_float() * 0.4;
+        self.audio
+            .play("minecraft:entity.generic.burn", Some(at), 0.4, pitch);
+    }
+    /// Whether a vehicle's box, deflated by 1e-5, reaches into lava below its
+    /// surface (`Entity.collidedWithFluid`).
+    pub(super) fn in_lava(&self, bb: Aabb) -> bool {
+        let (lo, hi) = (bb.min_position(), bb.max_position());
+        let e = 1.0e-5;
+        for x in (lo.x + e).floor() as i32..=(hi.x - e).floor() as i32 {
+            for y in (lo.y + e).floor() as i32..=(hi.y - e).floor() as i32 {
+                for z in (lo.z + e).floor() as i32..=(hi.z - e).floor() as i32 {
+                    if let Some((height, _)) = self.fluid_height_of(x, y, z, Some(Fluid::Lava))
+                        && lo.y + e < f64::from(y) + f64::from(height)
+                    {
+                        return true;
+                    }
+                }
+            }
+        }
+        false
    }
    /// The player's tick while riding: steer, tick the boat, sit in it.
    pub(super) fn tick_riding(&mut self, keys: Keys) -> horizon_client::Result<()> {
@@ -482,22 +605,35 @@ impl Game<'_> {
        self.yaw += b.delta_rotation;
        let delta = (self.yaw - b.yaw + 180.0).rem_euclid(360.0) - 180.0;
        self.yaw += delta.clamp(-105.0, 105.0) - delta;
+        self.boats[i] = b;
+        let seat = self.player_boat_seat(i);
        if let Some(p) = self.player.as_mut() {
            self.previous_position = p.position;
-            p.position = Vec3::new(b.position.x, b.position.y + SEAT, b.position.z);
+            p.position = seat;
            p.velocity = Vec3::ZERO;
            p.fall_distance = 0.0;
        }
-        self.boats[i] = b;
+        if self.boat_lava_tick(i) {
+            self.riding = None;
+        }
        Ok(())
    }
    /// `getDismountLocationForPassenger`: in front of the player if there is
    /// floor there, else on top of the boat.
    pub(super) fn dismount(&mut self, i: usize) {
        self.riding = None;
+        let target = self.boat_dismount_target(i, 0.6, self.yaw);
+        if let Some(p) = self.player.as_mut() {
+            p.position = target;
+            p.velocity = Vec3::ZERO;
+        }
+    }
+    /// `getDismountLocationForPassenger` for a passenger `width` wide
+    /// facing `yaw`.
+    pub(super) fn boat_dismount_target(&self, i: usize, width: f64, yaw: f32) -> Vec3 {
        let b = &self.boats[i];
-        let r = self.yaw.to_radians();
-        let distance = (WIDTH * std::f64::consts::SQRT_2 + 0.6 + 1.0e-5) / 2.0;
+        let r = yaw.to_radians();
+        let distance = (WIDTH * std::f64::consts::SQRT_2 + width + 1.0e-5) / 2.0;
        let (s, c) = (-(r.sin()) as f64, r.cos() as f64);
        let m = s.abs().max(c.abs());
        let (x, z) = (
@@ -508,17 +644,13 @@ impl Game<'_> {
        let (bx, by, bz) = (x.floor() as i32, top.floor() as i32, z.floor() as i32);
        let below = self.res.facts().get(self.world.block(bx, by - 1, bz));
        let here = self.res.facts().get(self.world.block(bx, by, bz));
-        let target = if below.fluid != Fluid::Water
+        if below.fluid != Fluid::Water
            && !here.full_collision
            && (below.full_collision || below.legacy_solid)
        {
            Vec3::new(x, f64::from(by), z)
        } else {
            Vec3::new(b.position.x, top, b.position.z)
-        };
-        if let Some(p) = self.player.as_mut() {
-            p.position = target;
-            p.velocity = Vec3::ZERO;
        }
    }
    /// `BoatItem.use`: aim at a block or the water surface.
@@ -534,7 +666,8 @@ impl Game<'_> {
        };
        let dir = view_vector(self.yaw, self.pitch);
        let reach = self.reach();
-        // ClipContext.Fluid.ANY: the first water surface or block along the ray.
+        // ClipContext.Fluid.ANY: the first fluid surface (water or lava) or
+        // block along the ray.
        let block = self.pick().map(|h| {
            (
                h.point,
@@ -544,7 +677,7 @@ impl Game<'_> {
                    .sqrt(),
            )
        });
-        let mut water = None;
+        let mut fluid = None;
        let mut t = 0.0;
        while t < reach {
            let p: [f64; 3] = std::array::from_fn(|a| eye[a] + dir[a] * t);
@@ -553,15 +686,15 @@ impl Game<'_> {
                p[1].floor() as i32,
                p[2].floor() as i32,
            );
-            if let Some((h, _)) = self.fluid_height(x, y, z)
+            if let Some((h, _)) = self.fluid_height_of(x, y, z, None)
                && p[1] <= f64::from(y) + f64::from(h)
            {
-                water = Some(([p[0], f64::from(y) + f64::from(h), p[2]], t));
+                fluid = Some(([p[0], f64::from(y) + f64::from(h), p[2]], t));
                break;
            }
            t += 0.05;
        }
-        let hit = match (block, water) {
+        let hit = match (block, fluid) {
            (Some(b), Some(w)) => {
                if w.1 < b.1 {
                    w.0
@@ -594,7 +727,7 @@ impl Game<'_> {
            binding: self.collision,
            subject: None,
        };
-        if !scene.unobstructed(inner).unwrap_or(false) {
+        if !scene.unobstructed(inner).unwrap_or(false) || self.boat_entity_collision(bb) {
            return false;
        }
        self.next_entity += 1;
@@ -649,7 +782,7 @@ impl Game<'_> {
            return false;
        }
        // ChestBoat.interact: sneaking (or a full seat) opens the chest.
-        if self.boats[i].chest && (sneaking || self.riding.is_some()) {
+        if self.boats[i].chest && (sneaking || self.riding.is_some() || !self.boat_has_room(i)) {
            let b = &self.boats[i];
            let key = (i32::MAX - 15, super::minecarts::CART_KEY_Y, b.id as i32);
            self.world.block_entities.insert(
@@ -666,6 +799,7 @@ impl Game<'_> {
            || self.boats[i].out_of_control >= 60.0
            || self.riding.is_some()
            || self.ridden_by_guest(self.boats[i].id)
+            || !self.boat_has_room(i)
        {
            return false;
        }
@@ -682,15 +816,24 @@ impl Game<'_> {
            return false;
        }
        self.vehicle_attack_sounds();
+        self.hurt_boat(i, damage, self.creative);
+        self.swing_arm();
+        true
+    }
+    /// `VehicleEntity.hurtServer`: wobble, add the damage and break past 40
+    /// (`creative`: a creative player's hit removes it without drops).
+    /// True when the boat was removed.
+    pub(super) fn hurt_boat(&mut self, i: usize, damage: f32, creative: bool) -> bool {
        let b = &mut self.boats[i];
        b.hurt_dir = -b.hurt_dir;
        b.hurt_time = 10;
        b.damage += damage * 10.0;
-        let destroyed = self.creative || b.damage > 40.0;
+        let destroyed = creative || b.damage > 40.0;
        if destroyed {
+            self.eject_boat_mobs(i, true);
            let b = self.boats.remove(i);
            let at = [b.position.x, b.position.y, b.position.z];
-            if !self.creative && self.ui.rules.bool("entity_drops") {
+            if !creative && self.ui.rules.bool("entity_drops") {
                // ChestBoat.destroy: chestVehicleDestroyed spills the contents.
                for stack in b.items.iter().flatten() {
                    self.spawn_item(stack.clone(), at, super::dispenser::new_item_motion(), 10);
@@ -709,8 +852,7 @@ impl Game<'_> {
                );
            }
        }
-        self.swing_arm();
-        true
+        destroyed
    }
    /// AbstractBoatRenderer.
    pub(super) fn boat_geometry(&self, camera: glam::DVec3, alpha: f64, out: &mut Vec<Vertex>) {
@@ -3,9 +3,10 @@
 //! pixels, 1024 characters, 100 pages), signing it into a written book,
 //! reading written books, and lecterns (placing a book, turning its pages
 //! with a redstone pulse, the comparator output and taking the book).
-use super::Game;
+use super::{Game, lan::LanHost};
 use horizon_client::{
    containers::{BlockEntity, Lectern},
+    first_person::Hand,
    hud::{HudBatch, rgba},
    item_data::WrittenBook,
    items::ItemStack,
@@ -14,6 +15,7 @@ use horizon_client::{
    ui,
 };
 use horizon_core::position::BlockPos;
+use horizon_protocol::packets::play::{self, Clientbound as C, Serverbound as S};
 use horizon_world::level::flags as level_flags;
 use std::time::Instant;
 use winit::{
@@ -48,9 +50,32 @@ impl Game<'_> {
    fn book_lines(&self, page: &str) -> Vec<Text> {
        self.gui.atlas.font.split(&Text::literal(page), 114.0)
    }
-    /// `WritableBookItem.use` / `WrittenBookItem.use`.
+    /// `WritableBookItem.use` / `WrittenBookItem.use` (`Player.openItemGui`).
+    /// A server's player writes in its own client's editor
+    /// (`LocalPlayer.openItemGui`), and reads on its own client once told to
+    /// (`ServerPlayer.openItemGui`'s ClientboundOpenBookPacket).
    pub(super) fn use_book(&mut self, stack: &ItemStack) -> bool {
-        let screen = match &*stack.item {
+        let written = match &*stack.item {
+            "minecraft:writable_book" => false,
+            "minecraft:written_book" => true,
+            _ => return false,
+        };
+        if self.lan_acting.is_some() {
+            if written {
+                let hand = i32::from(self.hand == Hand::Off);
+                self.guest_packets
+                    .push(C::OpenBook(play::OpenBook { hand }));
+            }
+        } else if let Some(screen) = self.book_screen(stack) {
+            self.open_book(screen);
+        }
+        self.swing_arm();
+        true
+    }
+    /// The screen a book in hand opens: `BookEditScreen` for a book and
+    /// quill, `BookViewScreen` for a written book.
+    fn book_screen(&self, stack: &ItemStack) -> Option<BookScreen> {
+        Some(match &*stack.item {
            "minecraft:writable_book" => {
                let mut pages = stack
                    .data()
@@ -77,12 +102,31 @@ impl Game<'_> {
                page: 0,
                lectern: None,
            },
-            _ => return false,
-        };
-        self.open_book(screen);
-        self.swing_arm();
+            _ => return None,
+        })
+    }
+    /// `MultiPlayerGameMode.useItem`'s own use of a book and quill on a
+    /// server's client: its editor opens here at once.
+    pub(super) fn remote_use_book(&mut self, stack: &ItemStack) -> bool {
+        if &*stack.item != "minecraft:writable_book" {
+            return false;
+        }
+        if let Some(screen) = self.book_screen(stack) {
+            self.open_book(screen);
+        }
        true
    }
+    /// `ClientPacketListener.handleOpenBook`: the written book in that hand.
+    pub(super) fn remote_open_book(&mut self, hand: i32) {
+        let hand = if hand == 1 { Hand::Off } else { Hand::Main };
+        let screen = self.with_hand(hand, |g| {
+            let stack = g.held().filter(|s| &*s.item == "minecraft:written_book")?;
+            g.book_screen(&stack.clone())
+        });
+        if let Some(screen) = screen {
+            self.open_book(screen);
+        }
+    }
    fn open_book(&mut self, screen: BookScreen) {
        self.book = Some(screen);
        self.keys.clear();
@@ -104,7 +148,9 @@ impl Game<'_> {
        self.book = None;
        self.capture(true);
    }
-    /// `BookEditScreen.saveChanges`: trailing empty pages dropped.
+    /// `BookEditScreen.saveChanges` and `BookSignScreen`'s Sign and Close:
+    /// trailing empty pages dropped, the book in hand updated here and, on a
+    /// server's client, sent (ServerboundEditBookPacket).
    fn save_book(&mut self, sign: bool) {
        let Some(BookScreen::Edit {
            slot, pages, title, ..
@@ -116,29 +162,59 @@ impl Game<'_> {
        while pages.len() > 1 && pages.last().is_some_and(String::is_empty) {
            pages.pop();
        }
-        if let Some(stack) = self.stack_in_mut(slot).as_mut()
-            && &*stack.item == "minecraft:writable_book"
-        {
-            if sign {
-                let mut written = ItemStack::new("minecraft:written_book", 1);
-                written.data_mut().written = Some(WrittenBook {
-                    title: title.trim().to_owned(),
-                    author: super::chat::PLAYER_NAME.to_owned(),
-                    generation: 0,
-                    pages,
-                });
-                *stack = written;
-            } else {
-                stack.data_mut().writable_pages = if pages.iter().all(String::is_empty) {
-                    Vec::new()
-                } else {
-                    pages
-                };
-                stack.tidy();
-            }
+        let title = sign.then(|| title.trim().to_owned());
+        if self.remote.is_some() {
+            self.send(S::EditBook(play::EditBook {
+                slot: slot as i32,
+                pages: pages.clone(),
+                title: title.clone(),
+            }));
        }
+        self.write_book(slot, pages, title);
        self.capture(true);
    }
+    /// The book and quill at `slot` takes the pages, or with a title becomes
+    /// the written book its writer signed.
+    fn write_book(&mut self, slot: usize, pages: Vec<String>, title: Option<String>) {
+        let author = self
+            .lan_acting_name
+            .clone()
+            .unwrap_or_else(|| super::chat::PLAYER_NAME.to_owned());
+        let Some(stack) = self
+            .stack_in_mut(slot)
+            .as_mut()
+            .filter(|s| &*s.item == "minecraft:writable_book")
+        else {
+            return;
+        };
+        if let Some(title) = title {
+            let mut written = ItemStack::new("minecraft:written_book", 1);
+            written.data_mut().written = Some(WrittenBook {
+                title,
+                author,
+                generation: 0,
+                pages,
+            });
+            *stack = written;
+        } else {
+            stack.data_mut().writable_pages = if pages.iter().all(String::is_empty) {
+                Vec::new()
+            } else {
+                pages
+            };
+            stack.tidy();
+        }
+    }
+    /// `ServerGamePacketListenerImpl.handleEditBook`: a guest's book in a
+    /// hotbar slot or its off hand (`updateBookContents`, `signBook`).
+    pub(super) fn lan_edit_book(&mut self, host: &mut LanHost, conn: u32, p: play::EditBook) {
+        if !((0..9).contains(&p.slot) || p.slot == super::shield::OFFHAND_SLOT as i32) {
+            return;
+        }
+        self.as_guest(host, conn, |g| {
+            g.write_book(p.slot as usize, p.pages, p.title)
+        });
+    }
    pub(super) fn book_key(&mut self, event: &KeyEvent) {
        if event.state != ElementState::Pressed {
            return;
@@ -519,7 +595,26 @@ impl Game<'_> {
                Some(key) => self.lectern_button(key, 3),
                None => return Err("not a lectern".into()),
            },
-            Some("done") => self.close_book(),
+            // The book and quill's buttons: Sign, then Sign and Close; Done
+            // (which saves), then Cancel.
+            Some("sign") => match self.book.as_mut() {
+                Some(BookScreen::Edit {
+                    signing: true,
+                    title,
+                    ..
+                }) if !title.trim().is_empty() => self.save_book(true),
+                Some(BookScreen::Edit { signing, .. }) => *signing = true,
+                _ => return Err("not a book and quill".into()),
+            },
+            Some("done") => match self.book.as_mut() {
+                Some(BookScreen::Edit { signing: true, .. }) => {
+                    if let Some(BookScreen::Edit { signing, .. }) = self.book.as_mut() {
+                        *signing = false;
+                    }
+                }
+                Some(BookScreen::Edit { .. }) => self.save_book(false),
+                _ => self.close_book(),
+            },
            Some(other) => return Err(format!("unknown book button {other}").into()),
        }
        Ok(match &self.book {
@@ -1,6 +1,6 @@
 //! Chat, the command registries and the per-world state behind commands
 //! (game rules, the world clock, difficulty), bound to the game.
-use super::{Dim, Game, Screen};
+use super::{Game, Screen};
 use horizon_client::{
    chat::{Chat, ChatAction, ChatScreen, Commands, SYSTEM_INDICATOR},
    command::Registries,
@@ -454,7 +454,7 @@ impl Game<'_> {
            return;
        }
        let focused = self.screen == Screen::Chat;
-        let heard = self.mods.mods.is_running().then(|| text.plain());
+        let heard = self.mods.running().then(|| text.plain());
        self.ui.chat.add(
            &self.gui.atlas,
            text,
@@ -583,7 +583,7 @@ impl Game<'_> {
                &[Text::literal(PLAYER_NAME), Text::literal(message)],
            );
            let focused = self.screen == Screen::Chat;
-            let heard = self.mods.mods.is_running().then(|| line.plain());
+            let heard = self.mods.running().then(|| line.plain());
            self.ui
                .chat
                .add(&self.gui.atlas, line, None, self.ticks, focused);
@@ -695,10 +695,7 @@ impl Game<'_> {
    /// Advance the overworld clock (ServerClockManager.tick) when
    /// `advance_time` allows it.
    pub(super) fn advance_clock(&mut self) {
-        if !self.ui.rules.bool("advance_time")
-            || self.ui.clock.paused
-            || self.dim == Dim::Nether && false
-        {
+        if !self.ui.rules.bool("advance_time") || self.ui.clock.paused {
            return;
        }
        let c = &mut self.ui.clock;
@@ -1783,8 +1783,11 @@ impl Game<'_> {
            self.level_set(pos, state)
                .map_err(|e| CommandError::new(Text::literal(e.to_string())))?;
        }
+        // LevelChunk.setBlockState creates it when the block, not the state, is still
+        // there after onPlace: a powered hopper turns itself `enabled=false`.
+        let landed = self.world.block(pos[0], pos[1], pos[2]);
        if old != new
-            && self.world.block(pos[0], pos[1], pos[2]) == state
+            && self.res.facts().get(landed).name == new
            && let Some(entity) = horizon_client::containers::BlockEntity::for_block(&new)
        {
            self.world.block_entities.insert(key, entity);
@@ -128,7 +128,7 @@ impl Game<'_> {
        if self.state_in_tag(avoid, ground) {
            return false;
        }
-        let entities = self.happy_ghast_player_collisions();
+        let entities = self.player_entity_collisions();
        let Some(player) = self.player.as_mut() else {
            return false;
        };
@@ -232,6 +232,13 @@ impl Game<'_> {
            "key" => {
                let key = key_code(arg(1)?).ok_or_else(|| format!("unknown key {}", words[1]))?;
                self.require_world()?;
+                // The sign editor takes raw presses (Enter, arrows, Backspace, Escape).
+                if self.sign_edit.is_some() {
+                    if arg(2)? != "up" {
+                        self.sign_input(Some(key), None);
+                    }
+                    return ok();
+                }
                // A held edit modifier (`key super down`) and A/C/V/X: the
                // open book's Select All, Copy, Paste or Cut.
                if self.book.is_some() && arg(2)? != "up" {
@@ -524,6 +531,10 @@ impl Game<'_> {
                    self.book_type(text);
                    return ok();
                }
+                if self.sign_edit.is_some() {
+                    self.sign_input(None, Some(text));
+                    return ok();
+                }
                match self.screen {
                    Screen::Chat => self.chat_type(text),
                    Screen::CommandBlock => self.command_block_type(text),
@@ -549,7 +560,7 @@ impl Game<'_> {
                    }
                    _ => {
                        return Err(
-                            "type needs the chat screen (key t tap), the language search, the creative search, the anvil or World Options".into(),
+                            "type needs the chat screen (key t tap), a sign or book, the language search, the creative search, the anvil or World Options".into(),
                        );
                    }
                }
@@ -578,7 +589,6 @@ impl Game<'_> {
                    "credits" => Page::Credits,
                    "horizon" => Page::Horizon,
                    "agent" => Page::Agent,
-                    "shader-packs" => Page::ShaderPacks,
                    other => return Err(format!("unknown options page {other}").into()),
                };
                if self.screen == Screen::Playing && self.title.is_none() {
@@ -977,6 +987,7 @@ impl Game<'_> {
            "flashes": self.lightning_seen[1], "flash": self.flash});
        // Primed TNT, falling blocks, projectiles, tridents and end crystals.
        status["projectiles"] = json!(self.projectiles_status());
+        status["maps"] = json!(self.maps_status());
        // The particles made so far, by type.
        status["particles"] = json!(self.particles.made());
        // The world border this side knows of.
@@ -47,6 +47,8 @@ pub(super) struct Creatures {
    pub pearl_cooldown: u32,
    /// The wind charge's use cooldown (ticks).
    pub wind_cooldown: u32,
+    /// Wind bursts from a guest's turn, waiting for it to end (game/wind.rs).
+    pub wind_bursts: Vec<super::wind::Burst>,
    /// Ticks left of the elder guardian's apparition (MobAppearanceParticle).
    pub elder_apparition: i32,
    /// The wandering trader spawner's clock.
@@ -1005,6 +1007,11 @@ impl Game<'_> {
                MobEvent::SetBlock { pos, state } => {
                    self.world.set(pos[0], pos[1], pos[2], state)?
                }
+                MobEvent::SetDoorOpen { pos, open } => {
+                    let pos = BlockPos::new(pos[0], pos[1], pos[2]);
+                    self.with_level(|b, level, ticks| b.set_door_open(level, ticks, pos, open));
+                    self.process_level_events()?;
+                }
                MobEvent::SetBlockName { pos, name, effect } => {
                    if effect {
                        let old = self.world.block(pos[0], pos[1], pos[2]);
@@ -1489,12 +1496,16 @@ impl Game<'_> {
                o.hurt
            }
        {
-            let (xd, zd) = (from[0] - player.position.x, from[2] - player.position.z);
-            self.knock_back_player(f64::from(0.4_f32), xd, zd);
-            if let Some(p) = self.player.as_mut()
-                && let Some(r) = p.hurt_log.last_mut()
-            {
-                r.knockback = Some([p.velocity.x, p.velocity.y, p.velocity.z]);
+            // LivingEntity.hurtServer's dealDefaultKnockback: not inside the
+            // hurt cooldown (a stronger hit there only adds its difference).
+            if o.knockback {
+                let (xd, zd) = (from[0] - player.position.x, from[2] - player.position.z);
+                self.knock_back_player(f64::from(0.4_f32), xd, zd);
+                if let Some(p) = self.player.as_mut()
+                    && let Some(r) = p.hurt_log.last_mut()
+                {
+                    r.knockback = Some([p.velocity.x, p.velocity.y, p.velocity.z]);
+                }
            }
            self.hurt_armor(amount);
            self.thorns(from);
@@ -1778,7 +1789,7 @@ impl Game<'_> {
                _ => self.projectile_hit(&p, hit)?,
            }
        }
-        Ok(())
+        self.flush_wind_bursts()
    }
    /// `projectile_hit` for a projectile the guest `conn` shot, run as them;
    /// as the host's when they have left.
@@ -38,7 +38,7 @@ impl DebugHost for Host<'_, '_> {
        // the menu as it always has (key_pressed).
        let g = &mut *self.game;
        if without_menu && g.screen == Screen::Playing {
-            g.pause_menu = !(g.has_singleplayer_server() && !g.is_published());
+            g.pause_menu = !g.has_singleplayer_server() || g.is_published();
            g.screen = Screen::Paused;
            g.capture(false);
            g.mining = None;
@@ -82,8 +82,10 @@ impl Game<'_> {
            }
            return true;
        }
-        // Screens with a text box take every key press first
-        // (EditBox.keyPressed); releases still reach KeyboardHandler.
+        // Vanilla types into a focused EditBox through charTyped, which no
+        // debug key can swallow. Here the character comes with the key press,
+        // so a screen with a focused text box takes every press first;
+        // releases still reach KeyboardHandler.
        let typing = matches!(
            self.screen,
            Screen::Chat | Screen::Options | Screen::WorldOptions | Screen::CommandBlock
@@ -91,7 +93,11 @@ impl Game<'_> {
            || self.book.is_some()
            || (self.screen == Screen::Creative && self.creative_screen.tab().search)
            || self.recipe_search_focused()
-            || self.station_typing();
+            || self.station_typing()
+            || self
+                .title
+                .as_mut()
+                .is_some_and(|t| t.focused_field().is_some());
        // Container screens use Escape, the inventory key and the hotbar and
        // drop keys first; any other screen closes on Escape.
        let screen_key = match self.screen {
@@ -593,7 +599,6 @@ impl Game<'_> {
            DebugAction::ReloadResourcePacks => {
                self.debug_translated("debug.reload_resourcepacks.message");
                self.reload_packs();
-                self.load_shader_pack();
                true
            }
            DebugAction::CopyLocation if player => {
@@ -608,6 +608,7 @@ impl Game<'_> {
                lang: Arc::new(horizon_client::net::load_language(&self.options.resources)),
                log_ips: props.log_ips,
            }),
+            resource_pack: props.resource_pack.clone(),
        };
        let config = HubConfig {
            default_game_mode: game_mode,
@@ -121,11 +121,13 @@ impl Game<'_> {
        let bonus = if knockback_attack { 0.5 } else { 0.0 };
        (enchanted / 2.0 + bonus, knockback_attack)
    }
-    /// `causeExtraKnockback`'s direction, `(sin yRot, -cos yRot)`: the target
-    /// flies where the attacker looks, not away from it.
+    /// `causeExtraKnockback`'s direction, `(sin yRot, -cos yRot)` from Mth's
+    /// sine table: the target flies where the attacker looks, not away from
+    /// it (straight along an axis when the attacker faces one).
    pub(super) fn extra_knockback_direction(&self) -> (f64, f64) {
-        let yaw = self.yaw.to_radians();
-        (f64::from(yaw.sin()), -f64::from(yaw.cos()))
+        use horizon_core::geometry::trig;
+        let yaw = f64::from(self.yaw * trig::DEG_TO_RAD);
+        (f64::from(trig::sin(yaw)), -f64::from(trig::cos(yaw)))
    }
    /// The attacker's side of `causeExtraKnockback` as the attacking client
    /// sees it: the server's player stops sprinting, and its flag reaches the
@@ -237,7 +237,7 @@ impl Game<'_> {
    /// the caller). The top left corner gives way to the debug screen.
    pub(super) fn draw_extras(&mut self, batch: &mut HudBatch) {
        let e = &self.settings.extras;
-        let mod_panels = self.mods.mods.panels().next().is_some();
+        let mod_panels = self.mods.has_panels();
        if !e.fps && !e.keystrokes && !e.minimap && !mod_panels {
            return;
        }
@@ -69,12 +69,18 @@ impl Game<'_> {
        let lo = Vec3::new(f.pos[0] - half, f.pos[1], f.pos[2] - half);
        let hi = Vec3::new(f.pos[0] + half, f.pos[1] + 0.8, f.pos[2] + half);
        let b = horizon_core::geometry::Aabb::new(lo, hi);
-        if let Some(p) = self.player_view()
-            && p.alive
-            && p.bounds.intersects(b)
-        {
-            self.mob_hits_player_kind(6.0, f.pos, "minecraft:indirect_magic");
-        }
+        // Every player in the box, the server's players too.
+        let pos = f.pos;
+        let bite = move |g: &mut Self| {
+            if let Some(p) = g.player_view()
+                && p.alive
+                && p.bounds.intersects(b)
+            {
+                g.mob_hits_player_kind(6.0, pos, "minecraft:indirect_magic");
+            }
+        };
+        bite(self);
+        self.each_guest_hit(bite);
        for m in &mut self.mobs {
            let ally = matches!(
                m.species(),
@@ -2,6 +2,7 @@
 //! bobbing, lure and bite timers, open water, hooking mobs, retrieving the
 //! `gameplay/fishing` loot) and `FishingHookRenderer` (bobber and line).
 use super::{Game, view_vector};
+use horizon_client::lan::{entity::States, hub::Hub};
 use horizon_client::{
    blocks::Fluid,
    collisions::SceneCollisions,
@@ -15,7 +16,10 @@ use horizon_core::{
    geometry::{Aabb, Vec3, trig},
    random::RandomSource,
 };
-use std::sync::Arc;
+use horizon_protocol::entity_data::{Value, serializer};
+use std::{collections::HashMap, sync::Arc};
+
+use super::lan_actions::GuestPlay;

 #[derive(Clone, Copy, Debug, PartialEq)]
 enum State {
@@ -24,6 +28,8 @@ enum State {
    Hooked(u32),
 }
 pub(super) struct Hook {
+    /// Its entity id, which a server's players track it under.
+    id: u32,
    position: Vec3,
    previous: Vec3,
    velocity: Vec3,
@@ -114,7 +120,9 @@ impl Game<'_> {
            );
            // A spawned hook's start position is its feet: centre the box on the eye.
            let start = Vec3::new(start.x, start.y - SIZE / 2.0, start.z);
+            self.next_entity += 1;
            self.hook = Some(Hook {
+                id: self.next_entity,
                position: start,
                previous: start,
                velocity: v,
@@ -562,12 +570,17 @@ impl Game<'_> {
            lerp(h.previous.z, h.position.z),
        ))
    }
-    /// FishingHookRenderer: the bobber, a camera-facing half-block quad
-    /// centred on the hook.
+    /// FishingHookRenderer: the bobbers (this player's and the others' a
+    /// server tracks), camera-facing half-block quads centred on the hooks.
    pub(super) fn fishing_geometry(&self, camera: glam::DVec3, alpha: f64, out: &mut Vec<Vertex>) {
-        let Some(p) = self.hook_position(alpha) else {
+        let hooks: Vec<glam::DVec3> = self
+            .hook_position(alpha)
+            .into_iter()
+            .chain(self.remote_hook_ends(alpha).into_iter().map(|(h, _)| h))
+            .collect();
+        if hooks.is_empty() {
            return;
-        };
+        }
        let Some(r) = self
            .gui
            .atlas
@@ -577,56 +590,57 @@ impl Game<'_> {
        else {
            return;
        };
-        let light = self
-            .world
-            .light(p.x.floor() as i32, p.y.floor() as i32, p.z.floor() as i32);
-        let packed = (u32::from(light >> 4) * 16) | ((u32::from(light & 15) * 16) << 8);
        let forward = glam::DVec3::from_array(view_vector(self.yaw, self.pitch));
        let right = forward.cross(glam::DVec3::Y).normalize_or_zero();
        let up = right.cross(forward).normalize_or_zero();
        let s = 0.25;
-        let corners = [
-            p - right * s - up * s,
-            p + right * s - up * s,
-            p + right * s + up * s,
-            p - right * s + up * s,
-        ];
        let uv = [[r.u0, r.v1], [r.u1, r.v1], [r.u1, r.v0], [r.u0, r.v0]];
-        for (v, uv) in corners.iter().zip(uv) {
-            out.push(Vertex {
-                normal: [0; 4],
-                pos: (*v - camera).as_vec3().to_array(),
-                uv,
-                layer: 0,
-                color: 0xFFFF_FFFF,
-                light: packed,
-            });
+        for p in hooks {
+            let light =
+                self.world
+                    .light(p.x.floor() as i32, p.y.floor() as i32, p.z.floor() as i32);
+            let packed = (u32::from(light >> 4) * 16) | ((u32::from(light & 15) * 16) << 8);
+            let corners = [
+                p - right * s - up * s,
+                p + right * s - up * s,
+                p + right * s + up * s,
+                p - right * s + up * s,
+            ];
+            for (v, uv) in corners.iter().zip(uv) {
+                out.push(Vertex {
+                    normal: [0; 4],
+                    pos: (*v - camera).as_vec3().to_array(),
+                    uv,
+                    layer: 0,
+                    color: 0xFFFF_FFFF,
+                    light: packed,
+                });
+            }
        }
    }
-    /// FishingHookRenderer: the line, 16 black `lines` segments sagging from
-    /// a quarter block above the hook to the rod in the player's hand,
+    /// FishingHookRenderer: each line, 16 black `lines` segments sagging
+    /// from a quarter block above the hook to the rod in its owner's hand,
    /// `width` pixels wide (`Window.getAppropriateLineWidth`).
    pub(super) fn fishing_line(&self, alpha: f64, size: [u32; 2]) -> Vec<Line> {
-        let (Some(hook), Some(hand)) = (
-            self.hook_position(alpha),
-            self.rod_hand_position(alpha, size),
-        ) else {
-            return Vec::new();
-        };
-        let offset = (hand - (hook + glam::DVec3::new(0.0, 0.25, 0.0))).as_vec3();
-        let point = |a: f32| {
-            let y = offset.y * (a * a + a) * 0.5 + 0.25;
-            hook + glam::Vec3::new(offset.x * a, y, offset.z * a).as_dvec3()
-        };
+        let own = self
+            .hook_position(alpha)
+            .zip(self.rod_hand_position(alpha, size));
        let width = horizon_client::gfx::outline_width(size[0]);
-        (0..16)
-            .map(|i| Line {
+        let mut lines = Vec::new();
+        for (hook, hand) in own.into_iter().chain(self.remote_hook_ends(alpha)) {
+            let offset = (hand - (hook + glam::DVec3::new(0.0, 0.25, 0.0))).as_vec3();
+            let point = |a: f32| {
+                let y = offset.y * (a * a + a) * 0.5 + 0.25;
+                hook + glam::Vec3::new(offset.x * a, y, offset.z * a).as_dvec3()
+            };
+            lines.extend((0..16).map(|i| Line {
                start: point(i as f32 / 16.0).to_array(),
                end: point((i + 1) as f32 / 16.0).to_array(),
                color: 0xFF00_0000,
                width,
-            })
-            .collect()
+            }));
+        }
+        lines
    }
    /// `FishingHookRenderer.getPlayerHandPos`: on the near plane in first
    /// person, beside the body otherwise.
@@ -694,6 +708,20 @@ impl Game<'_> {
    }
 }
 impl Game<'_> {
+    /// The hooks drawn here, with their owners' ids (0 for this player's own).
+    pub(super) fn hooks_status(&self) -> Vec<serde_json::Value> {
+        let at = |p: Vec3| [p.x, p.y, p.z];
+        let own = self.hook.iter().map(|h| (h.id, 0, h.position));
+        let others = self
+            .remote_hooks
+            .iter()
+            .map(|h| (h.id, h.owner, h.position));
+        own.chain(others)
+            .map(|(id, owner, p)| {
+                serde_json::json!({"id": id, "kind": "minecraft:fishing_bobber", "owner": owner, "position": at(p)})
+            })
+            .collect()
+    }
    /// The hook for `horizon-ctl status`.
    pub(super) fn hook_status(&self) -> Option<serde_json::Value> {
        let h = self.hook.as_ref()?;
@@ -706,3 +734,175 @@ impl Game<'_> {
        }))
    }
 }
+
+/// A hook a server tracks to this client (`FishingHook.recreateFromPacket`)
+/// that another player cast: drawn where the server puts it, its line
+/// running to that player's hand.
+pub(super) struct RemoteHook {
+    id: u32,
+    owner: u32,
+    position: Vec3,
+    previous: Vec3,
+}
+
+impl Hook {
+    /// This client's own hook as its server tracks it: drawn, never ticked here.
+    fn remote(id: u32, at: Vec3) -> Self {
+        Self {
+            id,
+            position: at,
+            previous: at,
+            velocity: Vec3::ZERO,
+            state: State::Flying,
+            life: 0,
+            on_ground: false,
+            nibble: 0,
+            time_until_lured: 0,
+            time_until_hooked: 0,
+            fish_angle: 0.0,
+            out_of_water: 0,
+            open_water: true,
+            luck: 0,
+            lure: 0,
+        }
+    }
+    /// `FishingHook`'s entity for the players tracking it: the owner's id in
+    /// its add packet, DATA_HOOKED_ENTITY (the hooked id plus one) and
+    /// DATA_BITING when they differ from their defaults.
+    fn track(&self, owner: i32, out: &mut States) {
+        let p = self.position;
+        let e = out.add(
+            self.id as i32,
+            super::lan::entity_uuid(self.id),
+            "minecraft:fishing_bobber",
+        );
+        e.position = [p.x, p.y, p.z];
+        e.velocity = [self.velocity.x, self.velocity.y, self.velocity.z];
+        e.on_ground = self.on_ground;
+        e.data = owner;
+        if let State::Hooked(id) = self.state {
+            e.meta.push((8, serializer::INT, Value::Int(id as i32 + 1)));
+        }
+        if self.nibble > 0 {
+            e.meta.push((9, serializer::BOOLEAN, Value::Bool(true)));
+        }
+    }
+}
+
+impl Game<'_> {
+    /// The hooks guests track: the host's and each guest's in the level.
+    pub(super) fn lan_hook_states(
+        &self,
+        host_entity: Option<i32>,
+        play: &HashMap<u32, GuestPlay>,
+        hub: &Hub,
+        out: &mut States,
+    ) {
+        if let (Some(h), Some(owner)) = (&self.hook, host_entity) {
+            h.track(owner, out);
+        }
+        for g in hub.guests.iter().filter(|g| hub.here(g)) {
+            if let Some(h) = play.get(&g.conn).and_then(|p| p.hook.as_ref()) {
+                h.track(g.entity_id, out);
+            }
+        }
+    }
+
+    /// `handleAddEntity` for a fishing bobber: this player's own becomes its
+    /// hook (`Player.fishing`), another player's is drawn on its line to them.
+    pub(super) fn spawn_remote_hook(&mut self, id: u32, at: Vec3, owner: i32) {
+        let own = self.remote.as_ref().map(|r| r.entity_id);
+        if own == Some(owner) {
+            self.hook = Some(Hook::remote(id, at));
+        } else {
+            self.remote_hooks.push(RemoteHook {
+                id,
+                owner: owner as u32,
+                position: at,
+                previous: at,
+            });
+        }
+    }
+
+    /// One tick of interpolation for the hooks a server tracks.
+    pub(super) fn step_remote_hooks(&mut self, mut step: impl FnMut(u32, Vec3) -> Vec3) {
+        if self.remote.is_none() {
+            return;
+        }
+        if let Some(h) = self.hook.as_mut() {
+            h.previous = h.position;
+            h.position = step(h.id, h.position);
+        }
+        for h in &mut self.remote_hooks {
+            h.previous = h.position;
+            h.position = step(h.id, h.position);
+        }
+    }
+
+    /// `FishingHook.onSyncedDataUpdated`: this player's hook is biting
+    /// (DATA_BITING), which `status` shows as a nibble.
+    pub(super) fn remote_hook_data(&mut self, id: u32, values: &[(u8, i32, Value)]) {
+        let Some(h) = self
+            .hook
+            .as_mut()
+            .filter(|h| h.id == id && self.remote.is_some())
+        else {
+            return;
+        };
+        for (index, _, value) in values {
+            if let (9, Value::Bool(biting)) = (index, value) {
+                h.nibble = i32::from(*biting);
+            }
+        }
+    }
+
+    pub(super) fn remove_remote_hook(&mut self, id: u32) {
+        if self.remote.is_some() && self.hook.as_ref().is_some_and(|h| h.id == id) {
+            self.hook = None;
+        }
+        self.remote_hooks.retain(|h| h.id != id);
+    }
+
+    pub(super) fn clear_remote_hooks(&mut self) {
+        if self.remote.is_some() {
+            self.hook = None;
+        }
+        self.remote_hooks.clear();
+    }
+
+    /// Other players' hooks: the bobber and its line to the owner's hand
+    /// (`FishingHookRenderer.getPlayerHandPos` in third person), as
+    /// (hook, hand) this frame.
+    fn remote_hook_ends(&self, alpha: f64) -> Vec<(glam::DVec3, glam::DVec3)> {
+        let lerp = |a: Vec3, b: Vec3| {
+            glam::DVec3::new(
+                a.x + (b.x - a.x) * alpha,
+                a.y + (b.y - a.y) * alpha,
+                a.z + (b.z - a.z) * alpha,
+            )
+        };
+        self.remote_hooks
+            .iter()
+            .filter_map(|h| {
+                let owner = self.mobs.iter().find(|m| m.id == h.owner)?;
+                let feet = lerp(owner.previous, owner.position);
+                let body = horizon_client::camera::lerp(
+                    alpha as f32,
+                    owner.previous_body_yaw,
+                    owner.body_yaw,
+                );
+                let angle = f64::from(body * (std::f64::consts::PI / 180.0) as f32);
+                let (sin, cos) = (f64::from(trig::sin(angle)), f64::from(trig::cos(angle)));
+                // The right arm; a crouching owner's eyes are lower.
+                let eye = owner.eye_y() - owner.position.y;
+                let hand = feet
+                    + glam::DVec3::new(
+                        -cos * 0.35 - sin * 0.8,
+                        eye - 0.45,
+                        -sin * 0.35 + cos * 0.8,
+                    );
+                Some((lerp(h.previous, h.position), hand))
+            })
+            .collect()
+    }
+}
@@ -200,7 +200,7 @@ impl Game<'_> {
            }
            Action::Copy => self.friends_copy(),
            Action::Stop => self.friends_stop(),
-            // The system browser, as the Shader Packs page opens its folder.
+            // The system browser, as the folder buttons open their folders.
            Action::Help => {
                if let Some(url) = &view.help {
                    super::packs::open_folder(std::path::Path::new(url));
@@ -3,6 +3,7 @@
 //! box each, and Done sending the changed ones (ServerboundSetGameRulePacket).
 //! Leaving with changes asks first (ConfirmScreen).
 use horizon_client::{
+    confirm_screen::Confirm,
    font::Font,
    gamerules::{self, GameRules, RULES, Rule, Value},
    hud::{HudAtlas, HudBatch},
@@ -66,9 +67,6 @@ fn parse(r: &Rule, s: &str) -> Option<i32> {
        .flatten()
        .filter(|v| (r.min..=r.max).contains(v))
 }
-fn widest(font: &Font, lines: &[Text]) -> f32 {
-    lines.iter().map(|l| font.width_text(l)).fold(0.0, f32::max)
-}
 fn lines(font: &Font, t: &Text, width: f32) -> Vec<Text> {
    font.split_lines(t, width)
        .into_iter()
@@ -95,38 +93,11 @@ fn yellow() -> u32 {
    named_color("yellow").unwrap_or(0xFFFF55)
 }

-/// ConfirmScreen: the title, the message (at most `width - 50` wide), and
-/// Yes / No 16 below, 4 apart, all centred.
-struct Confirm {
-    lines: Vec<(Text, f32, f32)>,
-    buttons: [(f32, f32); 2],
-}
-impl Confirm {
-    fn new(font: &Font, (w, h): (f32, f32)) -> Self {
-        let title = Text::translate("editGamerule.inGame.discardChanges.title", &[]);
-        let message = Text::translate("editGamerule.inGame.discardChanges.message", &[]);
-        let message: Vec<Text> = lines(font, &message, w - 50.0)
-            .into_iter()
-            .take(15)
-            .collect();
-        let (tw, mw) = (font.width_text(&title), widest(font, &message));
-        let mh = 9.0 * message.len() as f32;
-        let col = tw.max(mw).max(304.0);
-        let total = 9.0 + 8.0 + mh + 8.0 + 36.0;
-        let (lx, ly) = (((w - col) / 2.0).trunc(), ((h - total) / 2.0).trunc());
-        let cell = |cw: f32| lx + ((col - cw) / 2.0).trunc();
-        let mid = cell(mw) + (mw / 2.0).trunc();
-        let mut out = vec![(title, cell(tw), ly)];
-        for (i, line) in message.into_iter().enumerate() {
-            let x = mid - (font.width_text(&line) / 2.0).trunc();
-            out.push((line, x, ly + 17.0 + 9.0 * i as f32));
-        }
-        let (bx, by) = (cell(304.0), ly + 9.0 + 8.0 + mh + 8.0 + 16.0);
-        Self {
-            lines: out,
-            buttons: [(bx, by), (bx + 154.0, by)],
-        }
-    }
+/// ConfirmScreen "Game Rule Changes".
+fn confirm(font: &Font, size: (f32, f32)) -> Confirm {
+    let title = Text::translate("editGamerule.inGame.discardChanges.title", &[]);
+    let message = Text::translate("editGamerule.inGame.discardChanges.message", &[]);
+    Confirm::new(font, size, &title, &message)
 }

 impl RulesScreen {
@@ -301,13 +272,10 @@ impl RulesScreen {
        let (w, h) = size;
        let on = |x: f32, y: f32, bw: f32, bh: f32| ui::hovered(cursor, x, y, bw, bh);
        if self.confirm {
-            let c = Confirm::new(&atlas.font, size);
-            let [(yx, yy), (nx, ny)] = c.buttons;
-            if on(yx, yy, 150.0, 20.0) {
-                return Some(Exit::Discard);
-            }
-            if on(nx, ny, 150.0, 20.0) {
-                self.confirm = false;
+            match confirm(&atlas.font, size).answer_at(cursor) {
+                Some(true) => return Some(Exit::Discard),
+                Some(false) => self.confirm = false,
+                None => {}
            }
            return None;
        }
@@ -367,7 +335,7 @@ impl RulesScreen {
        let (w, h) = size;
        let on = |(x, y): (f32, f32)| ui::hovered(cursor, x, y, 150.0, 20.0);
        if self.confirm {
-            return Confirm::new(&atlas.font, size).buttons.into_iter().any(on);
+            return confirm(&atlas.font, size).answer_at(cursor).is_some();
        }
        let [done, cancel] = footer(w, h);
        if (on(done) && !self.invalid()) || on(cancel) {
@@ -384,15 +352,11 @@ impl RulesScreen {
        let (w, h) = (batch.width, batch.height);
        ui::menu_background(batch, atlas, 0.0, 0.0, w, h, true);
        if self.confirm {
-            let c = Confirm::new(&atlas.font, (w, h));
-            for (line, x, y) in &c.lines {
-                batch.text_styled(atlas, line, *x, *y, u32::MAX, true);
-            }
-            for ((bx, by), key) in c.buttons.into_iter().zip(["gui.yes", "gui.no"]) {
-                let hover = ui::hovered(cursor, bx, by, 150.0, 20.0);
-                let label = Text::translate(key, &[]);
-                ui::button(batch, atlas, bx, by, 150.0, 20.0, &label, true, hover);
-            }
+            let labels = [
+                Text::translate("gui.yes", &[]),
+                Text::translate("gui.no", &[]),
+            ];
+            confirm(&atlas.font, (w, h)).draw(batch, atlas, cursor, [&labels[0], &labels[1]]);
            return;
        }
        let rows = self.rows();
@@ -10,9 +10,10 @@ use horizon_core::geometry::{Aabb, Vec3};
 use horizon_world::registry::BlockStateId;

 impl Game<'_> {
-    /// Client `EntityGetter.getEntityCollisions`: only solid happy ghasts,
-    /// excluding the player's own vehicle.
-    pub(super) fn happy_ghast_player_collisions(&self) -> Vec<Aabb> {
+    /// Client `EntityGetter.getEntityCollisions` for the player: the
+    /// entities that `canBeCollidedWith` it, solid happy ghasts and boats
+    /// (`AbstractBoat.canBeCollidedWith`), except the player's own vehicle.
+    pub(super) fn player_entity_collisions(&self) -> Vec<Aabb> {
        let Some(p) = &self.player else {
            return Vec::new();
        };
@@ -24,6 +25,12 @@ impl Game<'_> {
                    && happy_ghast::collides_with_player(m, p.position.y)
            })
            .map(|m| m.bounds())
+            .chain(
+                self.boats
+                    .iter()
+                    .filter(|b| Some(b.id) != self.riding)
+                    .map(super::boats::Boat::bounds),
+            )
            .collect()
    }
    /// `HappyGhast.mobInteract`. Returns whether the click was used.
@@ -6,12 +6,10 @@
 //! the world's options) with [`Integrated::call`], as vanilla's client calls
 //! into its `IntegratedServer`.
 //!
-//! Opt-in again (`--server-thread` or `HORIZON_SERVER_THREAD=1`) until a
-//! server's players reach parity with the in-frame world: on the server
-//! thread, signs open no editor, books don't open, a totem doesn't save its
-//! holder and death keeps the inventory (#1380, #1366, #1292, #1284 and the
-//! other `[server-thread]` issues). LAN guests and dedicated servers use the
-//! same code either way.
+//! On by default. `--in-frame` (or `--no-server-thread`, or
+//! `HORIZON_SERVER_THREAD=0`) runs the world in the frame instead, the
+//! escape hatch. LAN guests and dedicated servers use the same code either
+//! way.
 use super::{
    Game, Options, PackResources, Resources, UiResources,
    lan::{LanSettings, Owner},
@@ -498,6 +496,22 @@ impl Game<'_> {
        out
    }

+    /// Run `f` with the owner's level in place (the server holds one per
+    /// dimension), then put back the level that was.
+    pub(super) fn in_owner_level<T>(&mut self, f: impl FnOnce(&mut Self) -> T) -> T {
+        let owner = self.serving.as_ref().map(|s| s.owner);
+        let dim = self.lan.as_ref().and_then(|h| {
+            let g = h.hub.guests.iter().find(|g| Some(g.uuid) == owner)?;
+            Some(super::Dim::from_id(&g.dimension))
+        });
+        let back = dim.and_then(|d| self.enter_command_level(d));
+        let out = f(self);
+        if let Some(back) = back {
+            self.enter_command_level(back);
+        }
+        out
+    }
+
    /// The window's requests, between two ticks.
    fn run_tasks(&mut self) {
        let tasks: Vec<Task> = match &self.serving {
@@ -411,7 +411,12 @@ impl Game<'_> {
                    "game_mode": g.game_mode,
                    // ItemCooldowns: the ticks the shield an axe disabled stays down.
                    "shield_cooldown": h.play.get(&g.conn).map_or(0, |p| p.shield_cooldown),
+                    // The item the server has this guest using: its slot and ticks.
+                    "using": h.play.get(&g.conn).and_then(|p| p.using())
+                        .map(|(slot, ticks)| json!({ "slot": slot, "ticks": ticks })),
                    "sneaking": g.sneaking,
+                    // The server's Elytra glide (shared flag 7).
+                    "fall_flying": g.fall_flying,
                    "sleeping": g.bed,
                    "health": g.health,
                    // The server's body: its air supply and golden hearts.
@@ -829,8 +834,11 @@ impl Game<'_> {
        self.lan_object_states(host_entity, hub, out);
    }

-    /// Run the hub for this tick and apply what the guests did.
-    pub(super) fn tick_lan(&mut self) {
+    /// Run the hub for this tick and apply what the guests did. While the
+    /// single player game is `paused` only the connections run
+    /// (`IntegratedServer.tickPaused`): `ServerGamePacketListenerImpl.tick`
+    /// skips `tickPlayer`, so no player's air, hunger or damage moves on.
+    pub(super) fn tick_lan(&mut self, paused: bool) {
        let Some(mut host) = self.lan.take() else {
            return;
        };
@@ -870,6 +878,7 @@ impl Game<'_> {
                    .collect();
                self.lan_riding(host_entity, &guests, &mut host.hub.riding);
                self.lan_entities(host_entity, &host.mob_players, &mut host.hub, &mut states);
+                self.lan_hook_states(host_entity, &host.play, &host.hub, &mut states);
            } else {
                states.clear();
            }
@@ -994,7 +1003,9 @@ impl Game<'_> {
            host.states = states;
        }
        self.lan_flush_effects(&mut host);
-        self.tick_guests(&mut host);
+        if !paused {
+            self.tick_guests(&mut host);
+        }
        self.lan_living_flags(&mut host);
        self.tick_server_travel(&mut host);
        self.lan_swings(&mut host);
@@ -1006,6 +1017,8 @@ impl Game<'_> {
        drop(holding);
        lan::flush_all(host.hub.guests.iter().map(|g| &g.sender));
        self.lan = Some(host);
+        // A mace's wind burst from a guest's attack.
+        let _ = self.flush_wind_bursts();
    }

    fn lan_guest_joined(
@@ -1061,6 +1074,7 @@ impl Game<'_> {
            }
            // A dedicated server has no host player.
            self.lan_entities(None, &host.mob_players, &mut host.hub, &mut theirs);
+            self.lan_hook_states(None, &host.play, &host.hub, &mut theirs);
            theirs.as_slice()
        } else {
            entities
@@ -30,6 +30,8 @@ use winit::keyboard::KeyCode;
 /// Per-guest state of the gameplay code that lives outside `Guest`.
 #[derive(Default)]
 pub(super) struct GuestPlay {
+    /// The sign this guest may write on (`SignBlockEntity.playerWhoMayEdit`).
+    pub(super) sign_editing: Option<[i32; 3]>,
    mining: Option<Mining>,
    destroy_delay: u32,
    using: Option<(usize, u32)>,
@@ -80,6 +82,8 @@ pub(super) struct GuestPlay {
    /// (`LivingEntity.collectEquipmentChanges`).
    modifiers: Vec<(String, String)>,
    equipped: Option<Vec<Option<ItemStack>>>,
+    /// The guest's cast fishing hook (`Player.fishing`).
+    pub(super) hook: Option<super::fishing::Hook>,
 }

 /// A guest's command waiting for the hub (`LanHost::commands`).
@@ -259,6 +263,7 @@ impl Game<'_> {
        motion.pitch = g.pitch;
        motion.sprinting = g.sprinting;
        motion.may_fly = g.creative() || g.game_mode == SPECTATOR;
+        motion.flying = g.flying;
        motion.invulnerable = motion.may_fly;
        let _ = motion.set_health(g.health, false);
        motion.health.food.food = g.food;
@@ -342,6 +347,7 @@ impl Game<'_> {
        std::mem::swap(&mut self.adv.unlocked, &mut g.recipes_unlocked);
        std::mem::swap(&mut self.level.recipe_book, &mut g.recipe_book);
        std::mem::swap(&mut self.stats, &mut play.stats);
+        std::mem::swap(&mut self.hook, &mut play.hook);
        let adv_loaded = std::mem::replace(&mut self.adv.loaded, true);
        let last_inventory = std::mem::replace(&mut self.adv.last_inventory, play.last_inventory);
        let death_cause = std::mem::replace(&mut self.ui.death_cause, play.death_cause.take());
@@ -513,7 +519,8 @@ impl Game<'_> {
        std::mem::swap(&mut self.mount, &mut play.mount);
        self.container = container;
        self.screen = screen;
-        self.sign_edit = host_sign;
+        // A sign the guest's placement opened (SignBlock.openTextEdit).
+        let guest_sign = std::mem::replace(&mut self.sign_edit, host_sign);
        // A lectern the guest's use opened (LecternBlock.openScreen).
        let guest_lectern = match std::mem::replace(&mut self.book, host_book) {
            Some(super::books::BookScreen::View {
@@ -548,6 +555,7 @@ impl Game<'_> {
        std::mem::swap(&mut self.adv.unlocked, &mut g.recipes_unlocked);
        std::mem::swap(&mut self.level.recipe_book, &mut g.recipe_book);
        std::mem::swap(&mut self.stats, &mut play.stats);
+        std::mem::swap(&mut self.hook, &mut play.hook);
        self.adv.loaded = adv_loaded;
        play.last_inventory = std::mem::replace(&mut self.adv.last_inventory, last_inventory);
        let stat_events = std::mem::take(&mut play.stats.events);
@@ -587,6 +595,11 @@ impl Game<'_> {
            // A teleport (commands, a pearl) moves the guest; a pearl's is
            // sent even to where they stand (ServerPlayer.teleport).
            let at = [m.position.x, m.position.y, m.position.z];
+            // A hit with extra knockback stopped the guest's sprint
+            // (Player.causeExtraKnockback's setSprinting(false)).
+            if !m.sprinting {
+                g.sprinting = false;
+            }
            m.sprinting = false;
            let teleported = std::mem::take(&mut m.teleported);
            let moved: f64 = (0..3).map(|k| (at[k] - g.position[k]).powi(2)).sum();
@@ -652,6 +665,9 @@ impl Game<'_> {
        if let Some(station) = opened_station {
            self.lan_station_opened(host, conn, station);
        }
+        if let Some(edit) = guest_sign {
+            self.lan_open_sign_editor(host, conn, edit);
+        }
        if let Some(key) = guest_lectern {
            self.lan_open_lectern(host, conn, key);
        }
@@ -865,14 +881,20 @@ impl Game<'_> {
                        self.as_guest(host, conn, |g| g.drop_held(a.action == 4));
                    }
                }
+                // RELEASE_USE_ITEM: ServerPlayer.releaseUsingItem, with the
+                // hand of the item in use acting.
                6 => {
                    self.as_guest(host, conn, |g| {
-                        if let Some((slot, ticks)) = g.using.take()
-                            && g.stack_in(slot)
-                                .is_some_and(|s| &*s.item == "minecraft:bow")
-                        {
-                            g.release_bow(ticks);
-                        }
+                        let Some(hand) = g.used_hand() else {
+                            return;
+                        };
+                        g.with_hand(hand, |g| {
+                            if let Some((slot, ticks)) = g.using.take()
+                                && let Some(stack) = g.stack_in(slot).cloned()
+                            {
+                                g.release_used_item(&stack, ticks, false);
+                            }
+                        });
                    });
                }
                // SWAP_ITEM_WITH_OFFHAND: the hands swap and the item in use stops
@@ -1029,30 +1051,27 @@ impl Game<'_> {
                    g.open_ridden_mount_menu();
                });
            }
+            S::PlayerCommand(p) if p.action == 6 => self.lan_start_gliding(host, conn),
            S::ContainerButtonClick(p) => {
                self.lan_station_button(host, conn, p.container, p.button);
            }
            S::RenameItem(p) => self.lan_station_rename(host, conn, &p.name),
+            S::SignUpdate(p) => self.lan_sign_update(host, conn, p),
+            S::EditBook(p) => self.lan_edit_book(host, conn, p),
            S::ContainerSlotStateChanged(p) => {
                self.lan_crafter_slot_state(host, conn, p.container, p.slot, p.enabled);
            }
            S::SetBeacon(p) => self.lan_station_beacon(host, conn, p.primary, p.secondary),
            S::SelectTrade(p) => self.lan_select_trade(host, conn, p.item),
            S::ContainerClose(p) if self.lan_merchant_closed(host, conn, Some(p.container)) => {
-                let g = &mut host.hub.guests[gi];
-                if let Some(c) = g.carried.take() {
-                    self.drop_guest_items(host, gi, vec![c]);
-                }
+                self.guest_carried_back(host, gi);
            }
            S::ContainerClose(p)
                if self.lan_crafting_closed(host, conn, Some(p.container))
                    || self.lan_station_closed(host, conn, Some(p.container))
                    || self.lan_mount_closed(host, conn, Some(p.container)) =>
            {
-                let g = &mut host.hub.guests[gi];
-                if let Some(c) = g.carried.take() {
-                    self.drop_guest_items(host, gi, vec![c]);
-                }
+                self.guest_carried_back(host, gi);
            }
            S::ContainerClick(p) => {
                let rules = ItemRules(self.res.items());
@@ -1068,10 +1087,7 @@ impl Game<'_> {
                    self.guest_container_closed(host, conn);
                }
                host.hub.container_closed(conn, p.container);
-                let g = &mut host.hub.guests[gi];
-                if let Some(c) = g.carried.take() {
-                    self.drop_guest_items(host, gi, vec![c]);
-                }
+                self.guest_carried_back(host, gi);
            }
            S::ChatCommand(c) => self.guest_chat_command(host, conn, &c.command),
            S::ChatCommandSigned(p) => self.guest_signed_command(host, conn, p),
@@ -1218,6 +1234,17 @@ impl Game<'_> {
        Some(out)
    }

+    /// `AbstractContainerMenu.removed`: what a closing player held on the
+    /// cursor goes back into their inventory (`placeItemBackInInventory`,
+    /// dropped only if it doesn't fit), and their client's cursor empties
+    /// with the inventory it is sent.
+    fn guest_carried_back(&mut self, host: &mut LanHost, gi: usize) {
+        if let Some(c) = host.hub.guests[gi].carried.take() {
+            self.lan_place_back(host, gi, vec![c]);
+            host.hub.send_inventory(gi);
+        }
+    }
+
    pub(super) fn drop_guest_items(&mut self, host: &LanHost, gi: usize, stacks: Vec<ItemStack>) {
        let g = &host.hub.guests[gi];
        let eye = [
@@ -1250,10 +1277,24 @@ impl Game<'_> {
        id: i32,
        location: Option<[f64; 3]>,
    ) -> Option<([f64; 3], [f64; 3])> {
+        let eye = {
+            let g = &host.hub.guests[gi];
+            [g.position[0], g.position[1] + g.eye_height(), g.position[2]]
+        };
        let object = || {
            let (lo, hi, origin) = self.object_target(id)?;
            let middle = [0, 1, 2].map(|k| (lo[k] + hi[k]) / 2.0);
            let Some(l) = location else {
+                // A boat's mobs sit over its middle: aim low at its near
+                // side, so the ray meets the boat before them (the server
+                // attacks the entity it is sent).
+                let carries = u32::try_from(id).is_ok_and(|v| {
+                    self.boats.iter().any(|b| b.id == v) && !self.boat_mobs(v).is_empty()
+                });
+                if carries {
+                    let near = |k: usize| eye[k].clamp(lo[k] + 0.01, hi[k] - 0.01);
+                    return Some([near(0), lo[1] + 0.05, near(2)]);
+                }
                return Some(middle);
            };
            let point = [0, 1, 2].map(|k| origin[k] + l[k]);
@@ -1284,7 +1325,6 @@ impl Game<'_> {
            }
        };
        let g = &mut host.hub.guests[gi];
-        let eye = [g.position[0], g.position[1] + g.eye_height(), g.position[2]];
        let d = [centre[0] - eye[0], centre[1] - eye[1], centre[2] - eye[2]];
        let horizontal = (d[0] * d[0] + d[2] * d[2]).sqrt();
        g.yaw = (-d[0].atan2(d[2])).to_degrees() as f32;
@@ -1300,8 +1340,11 @@ impl Game<'_> {
            return;
        }
        if let Some(victim) = Self::pvp_victim(host, conn, id) {
-            if let Some(Some(strike)) = self.as_guest(host, conn, |g| g.pvp_strike()) {
-                self.pvp_land(host, victim, &strike);
+            if let Some(Some(strike)) = self.as_guest(host, conn, |g| g.pvp_strike())
+                && self.pvp_land(host, victim, &strike)
+                && strike.stops_sprint()
+            {
+                self.as_guest(host, conn, |g| g.stop_sprint_after_extra_knockback());
            }
            return;
        }
@@ -1683,6 +1726,17 @@ impl Game<'_> {
                        g.use_delay -= 1;
                    }
                });
+                // ServerPlayerGameMode.handleBlockBreakAction: a creative
+                // player's START breaks the block once (destroyAndAck) and
+                // leaves nothing being destroyed; its client sends no STOP.
+                // Kept, the dig broke whatever was put there next, every
+                // destroy delay, for as long as the player broke nothing else.
+                if digging.is_some()
+                    && host.hub.guests[gi].creative()
+                    && let Some(play) = host.play.get_mut(&conn)
+                {
+                    play.digging = None;
+                }
            }
            // Player.tick: a different main-hand item resets the attack
            // strength, and detectEquipmentUpdates gives the guest its modifiers.
@@ -1704,16 +1758,23 @@ impl Game<'_> {
            // PlayerAdvancements.flushDirty.
            let sleeping = host.hub.guests[gi].sleeping;
            self.as_guest(host, conn, |g| {
+                g.tick_fishing();
+                g.tick_maps();
                g.count_tick_stats(sleeping);
                g.tick_advancements();
                g.update_player_attributes();
            });
+            self.lan_map_updates(host, conn);
            host.hub.flush_progress(conn);
            self.guest_dig_feedback(host, conn);
            self.guest_pickups(host, gi);
            self.guest_orbs(host, gi);
            if host.hub.guests[gi].health <= 0.0 && !host.hub.guests[gi].dead {
                self.guest_forget_digging(host, conn);
+                // FishingHook.shouldStopFishing: its owner is dead.
+                if let Some(play) = host.play.get_mut(&conn) {
+                    play.hook = None;
+                }
            }
            let g = &mut host.hub.guests[gi];
            if g.health <= 0.0 && !g.dead {
@@ -1727,6 +1788,9 @@ impl Game<'_> {
                }
                .death_reward(self.ui.rules.bool("keep_inventory") || g.game_mode == SPECTATOR);
                let (name, uuid) = (g.name.clone(), g.uuid);
+                // ServerPlayer.die: dropAllDeathLoot unless a spectator, from the eyes less 0.3.
+                let drops = (g.game_mode != SPECTATOR)
+                    .then(|| [at[0], at[1] + g.eye_height() - 0.3, at[2]]);
                let cause = host.play.get_mut(&conn).and_then(|p| p.death_cause.take());
                let message = match cause {
                    // ServerPlayer.die: the death message, to everyone unless
@@ -1760,6 +1824,9 @@ impl Game<'_> {
                );
                // LivingEntity.die: the death animation, the dying player included.
                host.hub.entity_event(id, 3, at);
+                if let Some(eyes) = drops {
+                    self.as_guest(host, conn, |game| game.drop_inventory(eyes));
+                }
                self.spawn_orbs(at, reward);
            }
        }
@@ -1846,6 +1913,13 @@ impl Game<'_> {
    /// sounds are heard at the guest.
    fn guest_server_tick(&mut self, host: &mut LanHost, conn: u32) {
        self.guest_vehicle_tick(host, conn);
+        // The last move's fall stands in for the server's delta movement.
+        let fell = host
+            .hub
+            .guest_mut(conn)
+            .and_then(|g| g.moves.last().map(|m| m.0[1]))
+            .unwrap_or(0.0);
+        self.guest_glide_tick(host, conn, fell);
        let Some(g) = host.hub.guest_mut(conn) else {
            return;
        };
@@ -1869,7 +1943,7 @@ impl Game<'_> {
            let (rules, motion) = (game.world.health_rules, game.motion);
            let health = &motion.health;
            let Some(player) = game.player.as_mut() else {
-                return Vec::new();
+                return (Vec::new(), None);
            };
            let mut w = MotionWorld {
                entities: &[],
@@ -1945,22 +2019,125 @@ impl Game<'_> {
            game.border_damage();
            game.tick_mob_effects();
            let Some(player) = game.player.as_mut() else {
-                return Vec::new();
+                return (Vec::new(), None);
            };
            let _ = player.peaceful_regeneration(rules);
            let _ = player.food_tick(health, rules);
            events.append(&mut player.events);
-            events
+            let _ = MotionWorld {
+                entities: &[],
+                player,
+                scene: &mut game.world,
+                assets: &game.pack.assets,
+                collision_binding: game.collision,
+                resources: game.motion,
+            }
+            .server_travel();
+            // A hurt since the last tick marked the velocity (Entity.markHurt):
+            // ServerEntity.sendChanges sends it as it is after this travel.
+            let marked = std::mem::take(&mut player.health.sync_velocity);
+            let sounds = events
                .into_iter()
                .filter_map(|e| match e {
                    MotionEvent::HurtSound(sound) => Some(sound),
                    _ => None,
                })
-                .collect::<Vec<_>>()
+                .collect::<Vec<_>>();
+            (sounds, marked.then_some(player.velocity))
        });
-        for sound in sounds.into_iter().flatten() {
+        let Some((sounds, marked)) = sounds else {
+            return;
+        };
+        for sound in sounds {
            self.player_hurt_sound(sound, at);
        }
+        if let (Some(v), Some(g)) = (marked, host.hub.guest(conn)) {
+            g.send(&C::SetEntityMotion(play::SetEntityMotion {
+                id: g.entity_id,
+                velocity: [v.x, v.y, v.z],
+            }));
+        }
+    }
+
+    /// ServerGamePacketListenerImpl.handlePlayerCommand START_FALL_FLYING:
+    /// `Player.tryToStartFallFlying`, or else `stopFallFlying` (a second
+    /// start while gliding ends the glide, as in vanilla).
+    fn lan_start_gliding(&mut self, host: &mut LanHost, conn: u32) {
+        let Some(g) = host.hub.guest_mut(conn) else {
+            return;
+        };
+        let start = !g.fall_flying && self.guest_can_glide(host, conn) == Some(true);
+        let in_liquid = self
+            .as_guest(host, conn, |game| {
+                game.player
+                    .as_ref()
+                    .is_some_and(|p| p.fluids.was_touching_water || p.is_in_lava())
+            })
+            .unwrap_or(true);
+        if let Some(g) = host.hub.guest_mut(conn) {
+            g.fall_flying = start && !in_liquid;
+        }
+    }
+
+    /// `Player.canGlide`: not flying, airborne, not riding, no levitation, and
+    /// a glider that its next point of wear won't break.
+    fn guest_can_glide(&mut self, host: &mut LanHost, conn: u32) -> Option<bool> {
+        let g = host.hub.guest_mut(conn)?;
+        if g.flying || g.on_ground || g.vehicle.is_some() {
+            return Some(false);
+        }
+        self.as_guest(host, conn, |game| {
+            game.glider_worn() && game.potions.effects.get("levitation").is_none()
+        })
+    }
+
+    /// `LivingEntity.updateFallFlying` on the server, once a tick for a
+    /// gliding guest: the glide ends once `canGlide` fails; otherwise every
+    /// 20th tick wears the glider by one, and every 10th is an
+    /// `elytra_glide` game event. Entity.checkFallDistanceAccumulation runs
+    /// first: a glide that isn't diving keeps the fall distance at 1.
+    fn guest_glide_tick(&mut self, host: &mut LanHost, conn: u32, fell: f64) {
+        let Some(g) = host.hub.guest_mut(conn) else {
+            return;
+        };
+        if !g.fall_flying {
+            if let Some(m) = g.motion.as_mut() {
+                m.fall_fly_ticks = 0;
+            }
+            return;
+        }
+        let creative = g.creative();
+        if let Some(m) = g.motion.as_mut()
+            && fell > -0.5
+            && m.fall_distance > 1.0
+        {
+            m.fall_distance = 1.0;
+        }
+        if self.guest_can_glide(host, conn) != Some(true) {
+            if let Some(g) = host.hub.guest_mut(conn) {
+                g.fall_flying = false;
+            }
+            return;
+        }
+        self.as_guest(host, conn, |game| {
+            let Some(p) = game.player.as_mut() else {
+                return;
+            };
+            p.fall_fly_ticks += 1;
+            let next = p.fall_fly_ticks + 1;
+            let at = [p.position.x, p.position.y, p.position.z];
+            if next % 10 != 0 {
+                return;
+            }
+            if (next / 10) % 2 == 0
+                && !creative
+                && let Some(elytra) = game.armor[1].as_mut()
+            {
+                elytra.damage += 1;
+            }
+            let ctx = game.player_context(None);
+            game.post_game_event("minecraft:elytra_glide", at, ctx);
+        });
    }

    /// `Player.isInWall`: a suffocating block in the 0.48-wide box at the
@@ -78,6 +78,8 @@ pub(super) fn acts_on_player(e: &MobEvent) -> bool {
                target: Who::Player,
                ..
            }
+            | MobEvent::EffectPlayer { .. }
+            | MobEvent::AxolotlSupportPlayer
    )
 }

@@ -115,6 +117,25 @@ impl Game<'_> {
        views
    }

+    /// Runs `f` as each guest in play here, for what strikes every player in
+    /// an area (`Level.getEntities`), not only the window's own.
+    pub(super) fn each_guest_hit(&mut self, mut f: impl FnMut(&mut Self)) {
+        let Some(mut host) = self.lan.take() else {
+            return;
+        };
+        let conns: Vec<u32> = host
+            .hub
+            .guests
+            .iter()
+            .filter(|g| host.hub.here(g) && g.loaded && !g.dead)
+            .map(|g| g.conn)
+            .collect();
+        for conn in conns {
+            self.guest_hit_by(&mut host, conn, &mut f);
+        }
+        self.lan = Some(host);
+    }
+
    /// Mob events aimed at a guest, run as that guest (`guest_hit_by`).
    pub(super) fn lan_guest_mob_events(&mut self, events: Vec<(u32, MobEvent)>) {
        if events.is_empty() {
@@ -192,7 +213,9 @@ impl Game<'_> {

 impl Game<'_> {
    /// Hurt a guest: `f` runs as them, and the knockback it gave reaches
-    /// their client (`hurtMarked`: ClientboundSetEntityMotionPacket).
+    /// their client. A hurt marks the velocity (Entity.markHurt), which goes
+    /// out once the guest's server copy has travelled (`guest_server_tick`);
+    /// a push with no hurt goes out at once.
    pub(super) fn guest_hit_by<R>(
        &mut self,
        host: &mut LanHost,
@@ -202,16 +225,47 @@ impl Game<'_> {
        let (result, pushed) = self.as_guest(host, conn, |g| {
            let before = g.player.as_ref().map(|p| p.velocity);
            let result = f(g);
-            let after = g.player.as_ref().map(|p| p.velocity);
-            (result, after.filter(|v| Some(*v) != before))
+            let pushed = g
+                .player
+                .as_ref()
+                .filter(|p| !p.health.sync_velocity && Some(p.velocity) != before)
+                .map(|p| p.velocity);
+            (result, pushed)
        })?;
-        if let (Some(v), Some(g)) = (pushed, host.hub.guest(conn)) {
+        self.send_guest_motion(host, conn, pushed);
+        Some(result)
+    }
+
+    /// A player's melee hit on a guest (Player.causeExtraKnockback on a
+    /// ServerPlayer): a hurt that marked the velocity sends it at once, and
+    /// the server's copy goes back to the velocity it had before the hit.
+    pub(super) fn guest_struck_by<R>(
+        &mut self,
+        host: &mut LanHost,
+        conn: u32,
+        f: impl FnOnce(&mut Self) -> R,
+    ) -> Option<R> {
+        let (result, sent) = self.as_guest(host, conn, |g| {
+            let before = g.player.as_ref().map(|p| p.velocity);
+            let result = f(g);
+            let sent = g.player.as_mut().zip(before).and_then(|(p, before)| {
+                std::mem::take(&mut p.health.sync_velocity)
+                    .then(|| std::mem::replace(&mut p.velocity, before))
+            });
+            (result, sent)
+        })?;
+        self.send_guest_motion(host, conn, sent);
+        Some(result)
+    }
+
+    /// ClientboundSetEntityMotionPacket to a guest about themselves.
+    pub(super) fn send_guest_motion(&self, host: &LanHost, conn: u32, velocity: Option<Vec3>) {
+        if let (Some(v), Some(g)) = (velocity, host.hub.guest(conn)) {
            g.send(&C::SetEntityMotion(play::SetEntityMotion {
                id: g.entity_id,
                velocity: [v.x, v.y, v.z],
            }));
        }
-        Some(result)
    }
 }

@@ -3,7 +3,7 @@
 //! `/particle` uses) and `ClientboundExplodePacket` (`ServerLevel.explode`).
 use super::Game;
 use horizon_client::particles::{ParticleOptions, ParticleType};
-use horizon_core::random::RandomSource;
+use horizon_core::{geometry::Vec3, random::RandomSource};
 use horizon_protocol::{
    entity_data::{Particle, ParticleData},
    packets::play::{self, Clientbound as C},
@@ -154,7 +154,7 @@ impl Game<'_> {
    }

    /// `ClientPacketListener.handleExplosion`: the blast's particles (and its
-    /// sound, when the packet carries it).
+    /// sound, when the packet carries it), then the player's push.
    pub(super) fn remote_explode(&mut self, p: &play::Explode) {
        if p.play_sound {
            let pitch = (1.0
@@ -168,37 +168,88 @@ impl Game<'_> {
                pitch,
            );
        }
-        let (world, facts) = (&self.world, self.res.facts());
-        self.particles
-            .explosion(p.center, p.radius, p.block_count.max(0) as usize, &|b| {
-                facts.is_air(world.block(b[0], b[1], b[2]))
-            });
+        if let Some(options) = self.received_particle(&p.particle, p.center) {
+            self.particles.add(&options, p.center, [1.0, 0.0, 0.0]);
+        }
+        // A wind charge's burst throws none.
+        if !p.block_particles.is_empty() {
+            let (world, facts) = (&self.world, self.res.facts());
+            self.particles.explosion_blocks(
+                p.center,
+                p.radius,
+                p.block_count.max(0) as usize,
+                &|b| facts.is_air(world.block(b[0], b[1], b[2])),
+            );
+        }
+        // Entity.pushFromExplosion.
+        if let (Some(push), Some(player)) = (p.knockback, self.player.as_mut()) {
+            player.velocity = Vec3::new(
+                player.velocity.x + push[0],
+                player.velocity.y + push[1],
+                player.velocity.z + push[2],
+            );
+        }
    }

    /// `ServerLevel.explode`'s packet to each player within 64 blocks. The
    /// sound and the push reach them on their own (the level's sounds, the
-    /// players' motion), so the packet carries neither.
+    /// motion a hurt player is sent), so the packet carries neither.
    pub(super) fn lan_explode(&self, center: [f64; 3], radius: f32, block_count: usize) {
-        let Some(host) = self.lan.as_ref() else {
-            return;
-        };
-        let particle = |name: &str| {
-            Some(Particle {
-                id: host.hub.registry_id("minecraft:particle_type", name)?,
-                data: None,
-            })
-        };
        let emitter = if radius < 2.0 {
            "minecraft:explosion"
        } else {
            "minecraft:explosion_emitter"
        };
-        let (Some(at_center), Some(poof), Some(smoke)) = (
-            particle(emitter),
-            particle("minecraft:poof"),
-            particle("minecraft:smoke"),
-        ) else {
-            return;
+        let sound = "minecraft:entity.generic.explode";
+        if let Some(packet) =
+            self.explosion_packet(center, radius, block_count, emitter, sound, true)
+        {
+            self.send_explosion(packet, &[]);
+        }
+    }
+
+    /// A wind charge's burst (`AbstractWindCharge.explode`): gust emitters,
+    /// no block particles, and for each player it pushed the push
+    /// (`ServerExplosion.hitPlayers`), which only that client applies, as
+    /// nothing hurt them.
+    pub(super) fn lan_wind_burst(
+        &self,
+        center: [f64; 3],
+        radius: f32,
+        sound: &str,
+        block_count: usize,
+        pushed: &[(u32, [f64; 3])],
+    ) {
+        let emitter = if radius < 2.0 {
+            "minecraft:gust_emitter_small"
+        } else {
+            "minecraft:gust_emitter_large"
+        };
+        if let Some(packet) =
+            self.explosion_packet(center, radius, block_count, emitter, sound, false)
+        {
+            self.send_explosion(packet, pushed);
+        }
+    }
+
+    /// `ClientboundExplodePacket` without a push, or None while not serving.
+    /// The sound is the level's, which the players hear already, so it isn't
+    /// played from the packet.
+    fn explosion_packet(
+        &self,
+        center: [f64; 3],
+        radius: f32,
+        block_count: usize,
+        emitter: &str,
+        sound: &str,
+        block_particles: bool,
+    ) -> Option<play::Explode> {
+        let hub = &self.lan.as_ref()?.hub;
+        let particle = |name: &str| {
+            Some(Particle {
+                id: hub.registry_id("minecraft:particle_type", name)?,
+                data: None,
+            })
        };
        // Level.DEFAULT_EXPLOSION_BLOCK_PARTICLES.
        let info = |particle, scaling| play::ExplosionParticle {
@@ -207,22 +258,49 @@ impl Game<'_> {
            speed: 1.0,
            weight: 1,
        };
-        let packet = C::Explode(play::Explode {
+        let block_particles = if block_particles {
+            vec![
+                info(particle("minecraft:poof")?, 0.5),
+                info(particle("minecraft:smoke")?, 1.0),
+            ]
+        } else {
+            Vec::new()
+        };
+        Some(play::Explode {
            center,
            radius,
            block_count: block_count as i32,
            knockback: None,
-            particle: at_center,
-            sound: match host
-                .hub
-                .registry_id("minecraft:sound_event", "minecraft:entity.generic.explode")
-            {
+            particle: particle(emitter)?,
+            sound: match hub.registry_id("minecraft:sound_event", sound) {
                Some(id) => (id, None),
-                None => (-1, Some(("minecraft:entity.generic.explode".into(), None))),
+                None => (-1, Some((sound.into(), None))),
            },
-            block_particles: vec![info(poof, 0.5), info(smoke, 1.0)],
+            block_particles,
            play_sound: false,
-        });
-        host.hub.broadcast_near(center, 64.0, &packet, None);
+        })
+    }
+
+    /// `packet` to each player within 64 blocks of its centre, with the push
+    /// `pushed` holds for them.
+    fn send_explosion(&self, mut packet: play::Explode, pushed: &[(u32, [f64; 3])]) {
+        let Some(host) = self.lan.as_ref() else {
+            return;
+        };
+        let center = packet.center;
+        let plain = C::Explode(packet.clone()).encode();
+        for g in host.hub.guests.iter().filter(|g| host.hub.here(g)) {
+            let d: f64 = (0..3).map(|k| (g.position[k] - center[k]).powi(2)).sum();
+            if d >= 4096.0 {
+                continue;
+            }
+            match pushed.iter().find(|(conn, _)| *conn == g.conn) {
+                Some((_, push)) => {
+                    packet.knockback = Some(*push);
+                    g.send(&C::Explode(packet.clone()));
+                }
+                None => g.sender.send(plain.clone()),
+            }
+        }
    }
 }
@@ -45,6 +45,14 @@ pub(super) struct Strike {
    team: Option<horizon_client::scoreboard::Team>,
 }

+impl Strike {
+    /// Whether it has extra knockback, which stops the attacker's sprint
+    /// once it lands (Player.causeExtraKnockback).
+    pub(super) fn stops_sprint(&self) -> bool {
+        self.knockback.0 > 0.0
+    }
+}
+
 impl Game<'_> {
    /// The guest on the host's crosshair and how far, within reach.
    pub(super) fn guest_hit(&self) -> Option<(u32, f64)> {
@@ -74,7 +82,7 @@ impl Game<'_> {
        };
        if let Some(strike) = self.pvp_strike()
            && self.pvp_land(&mut host, Victim::Guest(conn), &strike)
-            && strike.knockback.0 > 0.0
+            && strike.stops_sprint()
        {
            self.stop_sprint_after_extra_knockback();
        }
@@ -240,7 +248,7 @@ impl Game<'_> {
            && harm
            && match victim {
                Victim::Host => land(self),
-                Victim::Guest(conn) => self.guest_hit_by(host, conn, land).unwrap_or(false),
+                Victim::Guest(conn) => self.guest_struck_by(host, conn, land).unwrap_or(false),
            };
        let sound = match (hurt, s.crit, s.scale > 0.9) {
            (false, ..) => "minecraft:entity.player.attack.nodamage",
@@ -588,17 +588,7 @@ impl Game<'_> {
            let [x, y, z] = gs.pos;
            let name = &self.res.facts().get(self.world.block(x, y, z)).name;
            let block = StationKind::from_block(name) == Some(gs.kind);
-            let eye = [g.position[0], g.position[1] + g.eye_height(), g.position[2]];
-            // The block interaction range (4.5, creative 5) and the buffer.
-            let reach = if g.creative() { 5.0 } else { 4.5 } + 4.0;
-            let near = (0..3)
-                .map(|k| {
-                    let lo = f64::from(gs.pos[k]);
-                    (lo - eye[k]).max(eye[k] - lo - 1.0).max(0.0).powi(2)
-                })
-                .sum::<f64>()
-                < reach * reach;
-            if !(block && near) {
+            if !(block && within_reach(g, gs.pos)) {
                let window = gs.window;
                self.lan_station_closed(host, conn, Some(window));
                host.hub.send_to(
@@ -670,3 +660,18 @@ pub(super) fn station_inputs(gs: &GuestStation) -> Vec<ItemStack> {
        .map(|(_, _, inputs)| inputs.filter_map(|s| gs.menu.slot(s).cloned()).collect())
        .unwrap_or_default()
 }
+
+/// `Player.isWithinBlockInteractionRange(pos, 4)`: the guest's eyes within
+/// its block interaction range (4.5, creative 5) and a 4-block buffer of the
+/// block's box.
+pub(super) fn within_reach(g: &horizon_client::lan::guest::Guest, pos: [i32; 3]) -> bool {
+    let eye = [g.position[0], g.position[1] + g.eye_height(), g.position[2]];
+    let reach = if g.creative() { 5.0 } else { 4.5 } + 4.0;
+    (0..3)
+        .map(|k| {
+            let lo = f64::from(pos[k]);
+            (lo - eye[k]).max(eye[k] - lo - 1.0).max(0.0).powi(2)
+        })
+        .sum::<f64>()
+        < reach * reach
+}
@@ -9,7 +9,7 @@
 //! here with the rider's input (`ServerPlayer.getLastClientMoveIntent`).
 //! Sneaking gets out (`Player.rideTick`: `wantsToStopRiding`), and the client
 //! is teleported where the player lands (`ServerPlayer.dismountTo`).
-use super::{Game, Keys, boats::SEAT, lan::LanHost};
+use super::{Game, Keys, lan::LanHost, minecarts::SEAT};
 use horizon_client::collisions::SceneCollisions;
 use horizon_core::geometry::{Aabb, Vec3};
 use horizon_protocol::{
@@ -120,8 +120,8 @@ impl Game<'_> {
                    game.dismount(i);
                    return None;
                }
-                let p = game.boats[i].position;
-                return Some([p.x, p.y + SEAT, p.z]);
+                let p = game.player_boat_seat(i);
+                return Some([p.x, p.y, p.z]);
            }
            // The minecart moves with the rider's input, and lets it out when
            // it sneaks or the cart breaks. An animal takes the rider's input
@@ -161,19 +161,19 @@ impl Game<'_> {
        let at = self
            .boats
            .iter()
-            .find(|b| b.id == vehicle)
-            .map(|b| b.position)
+            .position(|b| b.id == vehicle)
+            .map(|i| (self.boats[i].position, self.player_boat_seat(i)))
            .or_else(|| {
                self.carts
                    .iter()
                    .find(|c| c.id == vehicle)
-                    .map(|c| c.position)
+                    .map(|c| (c.position, c.position.add_vector(Vec3::new(0.0, SEAT, 0.0))))
            });
-        if let Some(p) = at {
+        if let Some((p, seat)) = at {
            let g = &mut host.hub.guests[gi];
            g.vehicle_good = Some([p.x, p.y, p.z]);
            g.previous_position = g.position;
-            g.position = [p.x, p.y + SEAT, p.z];
+            g.position = [seat.x, seat.y, seat.z];
            g.on_ground = false;
            return;
        }
@@ -205,7 +205,9 @@ impl Game<'_> {
            return;
        };
        let [x, y, z] = p.position;
-        if !(x.is_finite() && y.is_finite() && z.is_finite())
+        if !x.is_finite()
+            || !y.is_finite()
+            || !z.is_finite()
            || !p.yaw.is_finite()
            || !p.pitch.is_finite()
        {
@@ -287,10 +289,11 @@ impl Game<'_> {
        b.previous_yaw = b.yaw;
        b.yaw = p.yaw;
        b.on_ground = p.on_ground;
+        let seat = self.player_boat_seat(i);
        let g = &mut host.hub.guests[gi];
        g.vehicle_good = Some([target.x, target.y, target.z]);
        g.previous_position = g.position;
-        g.position = [target.x, target.y + SEAT, target.z];
+        g.position = [seat.x, seat.y, seat.z];
    }

    /// `handlePaddleBoat`: the paddles of the boat the player drives.
@@ -296,7 +296,7 @@ impl Game<'_> {
            self.update_dedicated_streaming();
            self.update_world();
            result = if paused {
-                self.tick_lan();
+                self.tick_lan(true);
                Ok(())
            } else if k == 0 {
                self.tick()
@@ -280,11 +280,12 @@ impl Game<'_> {
    }
    /// `thunderHit` for entities within 3 blocks (up to 9 above).
    fn thunder_hit(&mut self, b: &mut Bolt) {
-        let inside = |p: [f64; 3]| {
-            (p[0] - b.at[0]).abs() <= 3.0
-                && (p[2] - b.at[2]).abs() <= 3.0
-                && p[1] >= b.at[1] - 3.0
-                && p[1] <= b.at[1] + 9.0
+        let at = b.at;
+        let inside = move |p: [f64; 3]| {
+            (p[0] - at[0]).abs() <= 3.0
+                && (p[2] - at[2]).abs() <= 3.0
+                && p[1] >= at[1] - 3.0
+                && p[1] <= at[1] + 9.0
        };
        let damage = Damage {
            kind: DamageKind::Generic,
@@ -349,19 +350,24 @@ impl Game<'_> {
        if !events.is_empty() {
            let _ = self.handle_mob_events(events);
        }
-        if let Some(p) = self.player.as_ref().map(|p| p.position)
-            && inside([p.x, p.y, p.z])
-        {
-            if let Some(p) = self.player.as_mut() {
-                p.fire_ticks += 1;
-                if p.fire_ticks == 0
-                    && let Err(error) = p.ignite_for_ticks(160)
-                {
-                    self.error = Some(error);
+        // Every player in the box, the server's players too.
+        let strike = move |g: &mut Self| {
+            if let Some(p) = g.player.as_ref().map(|p| p.position)
+                && inside([p.x, p.y, p.z])
+            {
+                if let Some(p) = g.player.as_mut() {
+                    p.fire_ticks += 1;
+                    if p.fire_ticks == 0
+                        && let Err(error) = p.ignite_for_ticks(160)
+                    {
+                        g.error = Some(error);
+                    }
                }
+                g.hurt_player_by("minecraft:lightning_bolt", 5.0);
            }
-            self.hurt_player_by("minecraft:lightning_bolt", 5.0);
-        }
+        };
+        strike(self);
+        self.each_guest_hit(strike);
        // Dropped items burn up (ItemEntity health 5), save fire-resistant ones.
        self.dropped.retain(|e| {
            !inside([e.position.x, e.position.y, e.position.z])
@@ -4,7 +4,7 @@
 //! shading, the dithered edge), the player marker, `data/minecraft/maps/<id>.dat` and
 //! `maps/last_id.dat`, the 128x128 texture in an atlas slot, the two-handed
 //! first-person view and maps in item frames.
-use super::Game;
+use super::{Game, lan::LanHost};
 use horizon_client::{
    blocks::{Fluid, MAP_COLORS},
    hud::{MAP_SLOTS, Rect},
@@ -14,13 +14,48 @@ use horizon_client::{
 use horizon_world::nbt::Tag;
 use std::collections::HashMap;

-/// A decoration: sprite, map position (-128..127, half pixels) and rotation (0..15).
+/// A decoration: sprite, map position (-128..127, half pixels) and rotation
+/// (0..15), and the player it marks (an item's own decorations mark none).
 #[derive(Clone, Debug, PartialEq)]
 pub(super) struct Decoration {
    pub sprite: &'static str,
    pub x: i8,
    pub y: i8,
    pub rot: u8,
+    pub holder: Option<u32>,
+}
+/// The host among a map's holders (the guests are their connections).
+const HOST: u32 = u32::MAX;
+/// A player carrying a map, or seeing it framed
+/// (`MapItemSavedData.HoldingPlayer`): the column sweep's step, and what
+/// changed since the last `ClientboundMapItemDataPacket` it was sent.
+struct Holder {
+    who: u32,
+    /// The last tick it carried the map, and saw it framed.
+    carried: i64,
+    framed: i64,
+    step: i32,
+    /// The changed pixels' box (min x, min y, max x, max y).
+    dirty: Option<[i32; 4]>,
+    decorations: bool,
+    tick: u32,
+}
+impl Holder {
+    fn new(who: u32) -> Self {
+        Self {
+            who,
+            carried: 0,
+            framed: 0,
+            step: 0,
+            dirty: Some([0, 0, 127, 127]),
+            decorations: true,
+            tick: 0,
+        }
+    }
+    /// Still carrying the map, or seeing it framed (frames tick every 10).
+    fn holds(&self, now: i64) -> bool {
+        self.carried + 1 >= now || self.framed + 10 >= now
+    }
 }
 pub(super) struct MapData {
    pub center: [i32; 2],
@@ -31,8 +66,7 @@ pub(super) struct MapData {
    pub unlimited: bool,
    pub colors: Vec<u8>,
    pub decorations: Vec<Decoration>,
-    /// HoldingPlayer.step for the column sweep.
-    step: i32,
+    holders: Vec<Holder>,
    /// Changed since the last save / texture upload.
    dirty: bool,
    texture_dirty: bool,
@@ -51,7 +85,7 @@ impl MapData {
            unlimited: false,
            colors: vec![0; 128 * 128],
            decorations: Vec::new(),
-            step: 0,
+            holders: Vec::new(),
            dirty: true,
            texture_dirty: true,
        }
@@ -64,8 +98,128 @@ impl MapData {
        self.colors[i] = color;
        self.dirty = true;
        self.texture_dirty = true;
+        // setColorsDirty: every holder's next packet carries it.
+        for h in &mut self.holders {
+            h.dirty = Some(match h.dirty {
+                Some([x0, y0, x1, y1]) => [x0.min(x), y0.min(y), x1.max(x), y1.max(y)],
+                None => [x, y, x, y],
+            });
+        }
        true
    }
+    /// `tickCarriedBy`'s holder for `who`, added when new.
+    fn holder(&mut self, who: u32) -> &mut Holder {
+        let i = match self.holders.iter().position(|h| h.who == who) {
+            Some(i) => i,
+            None => {
+                self.holders.push(Holder::new(who));
+                self.holders.len() - 1
+            }
+        };
+        &mut self.holders[i]
+    }
+    /// The holders that no longer carry the map nor see it framed go, and
+    /// their markers with them (`tickCarriedBy`'s removeDecoration).
+    fn drop_holders(&mut self, now: i64) {
+        self.holders.retain(|h| h.holds(now));
+        let holders = &self.holders;
+        let before = self.decorations.len();
+        self.decorations
+            .retain(|d| d.holder.is_none_or(|w| holders.iter().any(|h| h.who == w)));
+        if self.decorations.len() != before {
+            self.decorations_changed();
+        }
+    }
+    /// setDecorationsDirty.
+    fn decorations_changed(&mut self) {
+        for h in &mut self.holders {
+            h.decorations = true;
+        }
+    }
+    /// `addDecoration` / `removeDecoration` for `holder`'s marker: in place,
+    /// so that the order (the drawing order) stays.
+    fn set_marker(&mut self, holder: u32, marker: Option<Decoration>) {
+        let i = self
+            .decorations
+            .iter()
+            .position(|d| d.holder == Some(holder));
+        let changed = match (i, marker) {
+            (Some(i), Some(d)) if self.decorations[i] == d => false,
+            (Some(i), Some(d)) => {
+                self.decorations[i] = d;
+                true
+            }
+            (Some(i), None) => {
+                self.decorations.remove(i);
+                true
+            }
+            (None, Some(d)) => {
+                self.decorations.push(d);
+                true
+            }
+            (None, None) => false,
+        };
+        if changed {
+            self.decorations_changed();
+        }
+    }
+    /// `HoldingPlayer.nextUpdatePacket` for `who`: the changed pixels, and
+    /// the decorations (at most every 5th call while they changed).
+    fn update_packet(
+        &mut self,
+        id: i32,
+        who: u32,
+        kind: impl Fn(&str) -> Option<i32>,
+    ) -> Option<horizon_protocol::packets::play::MapItemData> {
+        use horizon_protocol::packets::play::{MapDecoration, MapItemData, MapPatch};
+        let h = self.holders.iter_mut().find(|h| h.who == who)?;
+        let patch = h.dirty.take().map(|[x0, y0, x1, y1]| {
+            let (width, height) = (x1 + 1 - x0, y1 + 1 - y0);
+            let mut colors = Vec::with_capacity((width * height) as usize);
+            for y in 0..height {
+                for x in 0..width {
+                    colors.push(self.colors[(x0 + x + (y0 + y) * 128) as usize]);
+                }
+            }
+            MapPatch {
+                start_x: x0,
+                start_y: y0,
+                width,
+                height,
+                colors,
+            }
+        });
+        let decorations = if h.decorations && {
+            let due = h.tick % 5 == 0;
+            h.tick += 1;
+            due
+        } {
+            h.decorations = false;
+            Some(
+                self.decorations
+                    .iter()
+                    .filter_map(|d| {
+                        Some(MapDecoration {
+                            kind: kind(decoration_type(d.sprite)?)?,
+                            x: d.x,
+                            y: d.y,
+                            rot: d.rot as i8,
+                            name: None,
+                        })
+                    })
+                    .collect(),
+            )
+        } else {
+            None
+        };
+        (patch.is_some() || decorations.is_some()).then_some(MapItemData {
+            map_id: id,
+            scale: self.scale as i8,
+            locked: self.locked,
+            decorations,
+            patch,
+        })
+    }
    fn to_nbt(&self) -> Tag {
        let flag = |b: bool| Tag::Byte(i8::from(b));
        Tag::compound([
@@ -112,7 +266,7 @@ impl MapData {
            unlimited: int("unlimitedTracking").unwrap_or(0) != 0,
            colors,
            decorations: Vec::new(),
-            step: 0,
+            holders: Vec::new(),
            dirty: false,
            texture_dirty: true,
        })
@@ -143,36 +297,48 @@ fn packed_rgba(packed: u8) -> [u8; 4] {
 pub(super) fn map_id(stack: &ItemStack) -> Option<i32> {
    stack.data().and_then(|d| d.map_id)
 }
-/// `MapDecorationTypes`: the sprite of a decoration type that a
-/// `minecraft:map_decorations` entry can name.
+/// `MapDecorationTypes` Horizon draws: (type, sprite).
+const DECORATION_TYPES: [(&str, &str); 24] = [
+    ("player", "map/decorations/player"),
+    ("frame", "map/decorations/frame"),
+    ("red_marker", "map/decorations/red_marker"),
+    ("blue_marker", "map/decorations/blue_marker"),
+    ("target_x", "map/decorations/target_x"),
+    ("target_point", "map/decorations/target_point"),
+    ("player_off_map", "map/decorations/player_off_map"),
+    ("player_off_limits", "map/decorations/player_off_limits"),
+    ("mansion", "map/decorations/woodland_mansion"),
+    ("monument", "map/decorations/ocean_monument"),
+    ("red_x", "map/decorations/red_x"),
+    ("village_desert", "map/decorations/desert_village"),
+    ("village_plains", "map/decorations/plains_village"),
+    ("village_savanna", "map/decorations/savanna_village"),
+    ("village_snowy", "map/decorations/snowy_village"),
+    ("village_taiga", "map/decorations/taiga_village"),
+    ("jungle_temple", "map/decorations/jungle_temple"),
+    ("swamp_hut", "map/decorations/swamp_hut"),
+    ("trial_chambers", "map/decorations/trial_chambers"),
+    ("abandoned_camp", "map/decorations/abandoned_camp"),
+    ("ancient_city", "map/decorations/ancient_city"),
+    ("desert_pyramid", "map/decorations/desert_pyramid"),
+    ("mineshaft", "map/decorations/mineshaft"),
+    ("ocean_ruin_warm", "map/decorations/warm_ocean_ruins"),
+];
+/// The sprite of a decoration type that a `minecraft:map_decorations`
+/// entry or a server's packet names.
 fn decoration_sprite(id: &str) -> Option<&'static str> {
-    Some(match id.strip_prefix("minecraft:").unwrap_or(id) {
-        "player" => "map/decorations/player",
-        "frame" => "map/decorations/frame",
-        "red_marker" => "map/decorations/red_marker",
-        "blue_marker" => "map/decorations/blue_marker",
-        "target_x" => "map/decorations/target_x",
-        "target_point" => "map/decorations/target_point",
-        "player_off_map" => "map/decorations/player_off_map",
-        "player_off_limits" => "map/decorations/player_off_limits",
-        "mansion" => "map/decorations/woodland_mansion",
-        "monument" => "map/decorations/ocean_monument",
-        "red_x" => "map/decorations/red_x",
-        "village_desert" => "map/decorations/desert_village",
-        "village_plains" => "map/decorations/plains_village",
-        "village_savanna" => "map/decorations/savanna_village",
-        "village_snowy" => "map/decorations/snowy_village",
-        "village_taiga" => "map/decorations/taiga_village",
-        "jungle_temple" => "map/decorations/jungle_temple",
-        "swamp_hut" => "map/decorations/swamp_hut",
-        "trial_chambers" => "map/decorations/trial_chambers",
-        "abandoned_camp" => "map/decorations/abandoned_camp",
-        "ancient_city" => "map/decorations/ancient_city",
-        "desert_pyramid" => "map/decorations/desert_pyramid",
-        "mineshaft" => "map/decorations/mineshaft",
-        "ocean_ruin_warm" => "map/decorations/warm_ocean_ruins",
-        _ => return None,
-    })
+    let name = id.strip_prefix("minecraft:").unwrap_or(id);
+    DECORATION_TYPES
+        .iter()
+        .find(|(n, _)| *n == name)
+        .map(|(_, sprite)| *sprite)
+}
+/// The type a decoration's sprite stands for, as its registry names it.
+fn decoration_type(sprite: &str) -> Option<&'static str> {
+    DECORATION_TYPES
+        .iter()
+        .find(|(_, s)| *s == sprite)
+        .map(|(name, _)| *name)
 }
 /// `minecraft:map_decorations` of a map item: (sprite, x, z, rotation), in
 /// the component's order.
@@ -275,12 +441,29 @@ impl Game<'_> {
        }
        self.maps.data.get_mut(&id)
    }
-    /// `ClientboundMapItemDataPacket.handle`: the server's colours for a map
-    /// this client does not own (lobby map art, a framed map on a wall).
+    /// `ClientboundMapItemDataPacket.handle`: the server's colours and
+    /// decorations for a map (one carried or framed on a server).
    pub(super) fn remote_map_item_data(
        &mut self,
        p: &horizon_protocol::packets::play::MapItemData,
    ) {
+        let decorations = p.decorations.as_ref().map(|list| {
+            let types = self
+                .remote
+                .as_ref()
+                .and_then(|r| r.builtin.get("minecraft:map_decoration_type"));
+            list.iter()
+                .filter_map(|d| {
+                    Some(Decoration {
+                        sprite: decoration_sprite(types?.name(d.kind)?)?,
+                        x: d.x,
+                        y: d.y,
+                        rot: (d.rot & 15) as u8,
+                        holder: None,
+                    })
+                })
+                .collect()
+        });
        let dimension = self.dimension_id();
        let map = self
            .maps
@@ -288,6 +471,9 @@ impl Game<'_> {
            .entry(p.map_id)
            .or_insert_with(|| MapData::fresh(0.0, 0.0, p.scale.max(0) as u8, dimension));
        map.locked = p.locked;
+        if let Some(decorations) = decorations {
+            map.decorations = decorations;
+        }
        let Some(patch) = &p.patch else {
            map.dirty = false;
            return;
@@ -566,10 +752,14 @@ impl Game<'_> {
            .collect();
        let (yaw, dim) = (self.yaw, self.dimension_id());
        let (nether, game_time) = (self.dim == super::Dim::Nether, self.world.game_time);
+        // The guest whose turn it is, else the host.
+        let me = self.lan_acting.unwrap_or(HOST);
        for (id, targets) in carried {
            let Some(m) = self.map(id) else { continue };
+            m.holder(me).carried = game_time;
+            m.drop_holders(game_time);
            // tickCarriedBy: the player marker while tracking in this dimension.
-            m.decorations.clear();
+            let mut marker = None;
            if m.tracking && m.dimension == dim {
                let s = f64::from(1 << m.scale);
                let dx = ((p.x - f64::from(m.center[0])) / s) as f32;
@@ -596,18 +786,19 @@ impl Game<'_> {
                } else {
                    None
                };
-                if let Some(sprite) = sprite {
-                    m.decorations.push(Decoration {
-                        sprite,
-                        x: clamp(dx),
-                        y: clamp(dz),
-                        rot,
-                    });
-                }
+                marker = sprite.map(|sprite| Decoration {
+                    sprite,
+                    x: clamp(dx),
+                    y: clamp(dz),
+                    rot,
+                    holder: Some(me),
+                });
            }
+            m.set_marker(me, marker);
            // The item's MAP_DECORATIONS (an explorer map's target), added
            // after the players as addDecoration would.
            let s = (1 << m.scale) as f32;
+            let mut items: Vec<Decoration> = Vec::new();
            for (sprite, x, z, rotation) in targets {
                let dx = (x - f64::from(m.center[0])) as f32 / s;
                let dz = (z - f64::from(m.center[1])) as f32 / s;
@@ -620,16 +811,95 @@ impl Game<'_> {
                    x: clamp_map_coordinate(dx),
                    y: clamp_map_coordinate(dz),
                    rot: decoration_rotation(nether, game_time, f64::from(rotation)),
+                    holder: None,
                };
-                if !m.decorations.contains(&d) {
-                    m.decorations.push(d);
+                if !items.contains(&d) {
+                    items.push(d);
                }
            }
+            if !m
+                .decorations
+                .iter()
+                .filter(|d| d.holder.is_none())
+                .eq(items.iter())
+            {
+                m.decorations.retain(|d| d.holder.is_some());
+                m.decorations.extend(items);
+                m.decorations_changed();
+            }
        }
        for id in held {
            self.update_map(id);
        }
    }
+    /// The maps the player carries, for `status`: how many of their pixels
+    /// are drawn, and their decorations.
+    pub(super) fn maps_status(&self) -> Vec<serde_json::Value> {
+        self.inventory
+            .iter()
+            .chain(std::iter::once(&self.offhand))
+            .flatten()
+            .filter_map(map_id)
+            .filter_map(|id| {
+                let m = self.maps.data.get(&id)?;
+                Some(serde_json::json!({
+                    "id": id,
+                    "pixels": m.colors.iter().filter(|&&c| c != 0).count(),
+                    "decorations": m.decorations.iter().map(|d| d.sprite).collect::<Vec<_>>(),
+                }))
+            })
+            .collect()
+    }
+    /// `ServerPlayer.synchronizeSpecialItemUpdates` for each map the guest
+    /// carries, and every 10 ticks (`ServerEntity.sendChanges`) for each map
+    /// framed in the level: a `ClientboundMapItemDataPacket` when something
+    /// changed since the guest's last one.
+    pub(super) fn lan_map_updates(&mut self, host: &LanHost, conn: u32) {
+        let Some(g) = host.hub.guest(conn) else {
+            return;
+        };
+        let mut ids: Vec<i32> = g
+            .inventory
+            .iter()
+            .chain(std::iter::once(&g.offhand))
+            .flatten()
+            .filter_map(map_id)
+            .collect();
+        let now = self.world.game_time;
+        if now % 10 == 0 && host.hub.here(g) {
+            let framed: Vec<i32> = self
+                .item_frames
+                .iter()
+                .filter_map(|f| f.item.as_ref().and_then(map_id))
+                .collect();
+            for id in framed {
+                if let Some(m) = self.map(id) {
+                    m.holder(conn).framed = now;
+                    ids.push(id);
+                }
+            }
+        }
+        ids.sort_unstable();
+        ids.dedup();
+        let kind = |name: &str| {
+            host.hub.registry_id(
+                "minecraft:map_decoration_type",
+                &format!("minecraft:{name}"),
+            )
+        };
+        for id in ids {
+            if let Some(p) = self
+                .maps
+                .data
+                .get_mut(&id)
+                .and_then(|m| m.update_packet(id, conn, kind))
+            {
+                g.send(&horizon_protocol::packets::play::Clientbound::MapItemData(
+                    p,
+                ));
+            }
+        }
+    }
    /// `MapItem.update` for the player holding map `id`.
    fn update_map(&mut self, id: i32) {
        let dim = self.dimension_id();
@@ -651,8 +921,9 @@ impl Game<'_> {
        if nether {
            radius /= 2;
        }
-        m.step += 1;
-        let step = m.step;
+        let h = m.holder(self.lan_acting.unwrap_or(HOST));
+        h.step += 1;
+        let step = h.step;
        let mut changes: Vec<(i32, i32, u8)> = Vec::new();
        let mut consecutive = false;
        for img_x in px - radius + 1..px + radius {
@@ -918,21 +1189,17 @@ impl Game<'_> {
            );
        }
    }
-    /// `renderTwoHandedMap`: the held map (main hand, empty off hand) in view space.
-    pub(super) fn held_map_geometry(
+    /// `renderTwoHandedMap`: map `id` held in both hands, in view space (the
+    /// arms under it are not drawn).
+    pub(super) fn two_handed_map_geometry(
        &mut self,
        to_world: glam::Mat4,
        attack: f32,
        inverse_height: f32,
+        id: i32,
        light: u32,
        out: &mut Vec<Vertex>,
-    ) -> bool {
-        let Some(id) = self.inventory[self.selected].as_ref().and_then(map_id) else {
-            return false;
-        };
-        if self.offhand.is_some() {
-            return false;
-        }
+    ) {
        let deg = |d: f32| d.to_radians();
        let sqrt_attack = attack.sqrt();
        let y_swing = -0.2 * (attack * std::f32::consts::PI).sin();
@@ -949,10 +1216,16 @@ impl Game<'_> {
            ))
            * glam::Mat4::from_rotation_x(deg(tilt * -85.0));
        let swing = (sqrt_attack * std::f32::consts::PI).sin();
-        // renderMap: background (with 7-pixel border) then the map.
        let m = base
            * glam::Mat4::from_rotation_x(deg(swing * 20.0))
-            * glam::Mat4::from_scale(glam::Vec3::splat(2.0))
+            * glam::Mat4::from_scale(glam::Vec3::splat(2.0));
+        self.held_map(m, id, light, out);
+    }
+    /// `renderMap`: map `id` at pose `m`, its background (with a 7-pixel
+    /// border) then the map.
+    pub(super) fn held_map(&mut self, m: glam::Mat4, id: i32, light: u32, out: &mut Vec<Vertex>) {
+        let deg = |d: f32| d.to_radians();
+        let m = m
            * glam::Mat4::from_rotation_y(deg(180.0))
            * glam::Mat4::from_rotation_z(deg(180.0))
            * glam::Mat4::from_scale(glam::Vec3::splat(0.38))
@@ -984,7 +1257,6 @@ impl Game<'_> {
        if has_data {
            self.map_vertices(id, m, light, out);
        }
-        true
    }
 }

@@ -95,7 +95,7 @@ fn display_offset(kind: CartKind) -> f64 {
    if kind == CartKind::Hopper { 1.0 } else { 6.0 }
 }
 /// The minecart's passenger attachment minus Player.DEFAULT_VEHICLE_ATTACHMENT.
-const SEAT: f64 = 0.1875 - 0.6;
+pub(super) const SEAT: f64 = 0.1875 - 0.6;
 /// The placeholder container key under which an open cart's items live.
 pub(super) const CART_KEY_Y: i32 = -100_000;

@@ -686,40 +686,53 @@ impl Game<'_> {
            }
        }
    }
-    /// `AbstractMinecart.push(player)` when the player walks into a cart.
+    /// `AbstractMinecart.push` from each player walking into a cart
+    /// (`LivingEntity.pushEntities`): the window's player and every server
+    /// player (single player's own on its server thread, LAN guests). A
+    /// player in a vehicle pushes nothing here. The quarter push the player
+    /// gets back only moves the server's copy of it (`Entity.push` marks
+    /// `needsSync`, which `ServerEntity` sends to the other players only),
+    /// so no player feels it.
    fn push_carts(&mut self) {
-        let player = self.player.as_ref().map(|p| p.position);
-        let riding = self.riding;
-        for i in 0..self.carts.len() {
-            if Some(self.carts[i].id) == riding {
-                continue;
+        if self.carts.is_empty() {
+            return;
+        }
+        // (feet, box)
+        let mut pushers: Vec<(Vec3, Aabb)> = Vec::new();
+        if self.riding.is_none()
+            && let Some(p) = self.player.as_ref()
+        {
+            pushers.push((p.position, p.bounds()));
+        }
+        if let Some(host) = self.lan.as_ref() {
+            for g in host.hub.guests.iter().filter(|g| {
+                host.hub.here(g) && g.loaded && !g.dead && !g.spectator() && g.vehicle.is_none()
+            }) {
+                let [x, y, z] = g.position;
+                let height = if g.sneaking { 1.5 } else { 1.8 };
+                let bb = Aabb::new(
+                    Vec3::new(x - 0.3, y, z - 0.3),
+                    Vec3::new(x + 0.3, y + height, z + 0.3),
+                );
+                pushers.push((Vec3::new(x, y, z), bb));
            }
-            if let Some(pp) = player {
-                let bb = self.carts[i].bounds();
-                let (lo, hi) = (bb.min_position(), bb.max_position());
-                let touching = pp.x + 0.3 > lo.x
-                    && pp.x - 0.3 < hi.x
-                    && pp.z + 0.3 > lo.z
-                    && pp.z - 0.3 < hi.z
-                    && pp.y + 1.8 > lo.y
-                    && pp.y < hi.y;
-                if touching && riding.is_none() {
-                    let c = &mut self.carts[i];
-                    let (mut xa, mut za) = (pp.x - c.position.x, pp.z - c.position.z);
-                    let dd = xa * xa + za * za;
-                    if dd >= 1.0e-4 {
-                        let d = dd.sqrt();
-                        let pow = (1.0 / d).min(1.0);
-                        xa = xa / d * pow * f64::from(0.1f32) * 0.5;
-                        za = za / d * pow * f64::from(0.1f32) * 0.5;
-                        c.velocity.x -= xa;
-                        c.velocity.z -= za;
-                        if let Some(p) = self.player.as_mut() {
-                            p.velocity.x += xa / 4.0;
-                            p.velocity.z += za / 4.0;
-                        }
-                    }
+        }
+        for (feet, bb) in pushers {
+            for c in &mut self.carts {
+                if !bb.intersects(c.bounds()) {
+                    continue;
                }
+                let (mut xa, mut za) = (feet.x - c.position.x, feet.z - c.position.z);
+                let dd = xa * xa + za * za;
+                if dd < f64::from(1.0e-4f32) {
+                    continue;
+                }
+                let d = dd.sqrt();
+                let pow = (1.0 / d).min(1.0);
+                xa = xa / d * pow * f64::from(0.1f32) * 0.5;
+                za = za / d * pow * f64::from(0.1f32) * 0.5;
+                c.velocity.x -= xa;
+                c.velocity.z -= za;
            }
        }
    }
@@ -797,7 +810,7 @@ impl Game<'_> {
        let ridden = self.guest_vehicles();
        // By id: an exploding cart can destroy or prime others mid-loop.
        let ids: Vec<u32> = self.carts.iter().map(|c| c.id).collect();
-        for id in ids {
+        for &id in &ids {
            let Some(i) = self.carts.iter().position(|c| c.id == id) else {
                continue;
            };
@@ -823,6 +836,33 @@ impl Game<'_> {
                self.carts.remove(i);
            }
        }
+        // On the server for every cart, the ridden ones too.
+        for id in ids {
+            if let Some(i) = self.carts.iter().position(|c| c.id == id) {
+                let p = self.carts[i].position;
+                if ticking(p.x.floor() as i32, p.z.floor() as i32) {
+                    self.cart_lava_tick(id);
+                }
+            }
+        }
+    }
+    /// `lavaHurt` twice a tick in lava: from `LavaFluid.entityInside` in the
+    /// behaviour's `applyEffectsFromBlocks`, then from `AbstractMinecart.tick`'s
+    /// own `isInLava`. The second breaks the cart, or primes a TNT minecart
+    /// (`MinecartTNT.destroy` for a fire source). A cart has no `baseTick`,
+    /// so the fire `lavaIgnite` lights never burns it.
+    fn cart_lava_tick(&mut self, id: u32) {
+        for _ in 0..2 {
+            let Some(i) = self.carts.iter().position(|c| c.id == id) else {
+                return;
+            };
+            if !self.in_lava(self.carts[i].bounds()) {
+                return;
+            }
+            let p = self.carts[i].position;
+            self.hurt_cart(i, 4.0, false, true);
+            self.lava_hurt_sound([p.x, p.y, p.z]);
+        }
    }
    /// `ClientPacketListener.postAddEntitySoundInstance` for the carts that
    /// joined the level since the last tick, and `LocalPlayer.startRiding`'s
@@ -2,43 +2,76 @@
 //! their tick, frame, chat and command hooks, their HUD panels and what
 //! they print. With no mod on, `horizon_mods::Mods` holds no engine and
 //! every hook here returns after one check.
-use super::{Game, Screen};
+//!
+//! Code mods run only in builds with the `mods` feature (release builds):
+//! without it the game links no wasmtime, and every hook does nothing.
+//! Content mods (`content_root`) load in every build.
+use super::Game;
 use horizon_client::{
    command::{Dispatcher, vanilla},
-    extras::Corner,
-    extras_hud::{self, Corners},
+    extras_hud::Corners,
    hud::HudBatch,
-    mod_list::{self, Installed},
-    text::{self, Text},
+    mod_list,
 };
-use horizon_mods::{Clock, Mods, Output, Player, Snapshot, Status};
-use std::{
-    path::PathBuf,
-    time::{Duration, Instant},
+use std::{path::PathBuf, time::Duration};
+#[cfg(feature = "mods")]
+use {
+    super::Screen,
+    horizon_client::{
+        extras::Corner,
+        extras_hud,
+        mod_list::Installed,
+        text::{self, Text},
+    },
+    horizon_mods::{Clock, Mods, Output, Player, Snapshot, Status},
+    std::time::Instant,
 };

 #[derive(Default)]
 pub(super) struct ModsState {
-    pub(super) mods: Mods,
+    #[cfg(feature = "mods")]
+    mods: Mods,
    /// `--dev-mod PATH`: always on, reloaded when rebuilt.
    pub(super) dev: Vec<PathBuf>,
    /// When dev mods were last checked for a rebuild.
+    #[cfg(feature = "mods")]
    checked: Option<Instant>,
    /// The chat's command tree while a running mod owns commands.
+    #[cfg(feature = "mods")]
    tree: Option<Dispatcher>,
 }
 impl ModsState {
    /// The chat's command tree: vanilla's, plus the running mods' commands.
    pub(super) fn dispatcher(&self) -> &Dispatcher {
-        self.tree
-            .as_ref()
-            .unwrap_or_else(|| vanilla::game_dispatcher())
+        #[cfg(feature = "mods")]
+        if let Some(tree) = &self.tree {
+            return tree;
+        }
+        vanilla::game_dispatcher()
+    }
+    /// Whether a mod runs: the chat keeps its lines for them.
+    pub(super) fn running(&self) -> bool {
+        #[cfg(feature = "mods")]
+        if self.mods.is_running() {
+            return true;
+        }
+        false
+    }
+    /// Whether a mod draws a HUD panel.
+    pub(super) fn has_panels(&self) -> bool {
+        #[cfg(feature = "mods")]
+        if self.mods.panels().next().is_some() {
+            return true;
+        }
+        false
    }
 }
 /// How often dev mods are checked for a rebuild.
+#[cfg(feature = "mods")]
 const RELOAD_CHECK: Duration = Duration::from_secs(1);

 /// A vanilla command name: mods may not take it.
+#[cfg(feature = "mods")]
 fn vanilla_command(name: &str) -> bool {
    let d = vanilla::game_dispatcher();
    d.nodes[0]
@@ -112,6 +145,30 @@ pub(super) fn content_root(
    }
 }

+/// A build without the `mods` feature: no mod runs.
+#[cfg(not(feature = "mods"))]
+impl Game<'_> {
+    /// Says why the installed and dev mods don't run.
+    pub(super) fn start_mods(&mut self) {
+        let dir = Self::options_path().with_file_name(mod_list::DIR);
+        let found = horizon_mods::find(&dir).len() + self.mods.dev.len();
+        if found > 0 {
+            log::warn!(
+                "Horizon: {found} mod(s) not started: this build has no mod runtime (build with --features mods)"
+            );
+        }
+    }
+    pub(super) fn sync_mods(&mut self) {}
+    pub(super) fn tick_mods(&mut self) {}
+    pub(super) fn mods_frame(&mut self, _elapsed: Duration) {}
+    pub(super) fn mod_command(&mut self, _command: &str) -> bool {
+        false
+    }
+    pub(super) fn mods_chat(&mut self, _line: &str) {}
+    pub(super) fn draw_mod_panels(&self, _batch: &mut HudBatch, _corners: &mut Corners) {}
+}
+
+#[cfg(feature = "mods")]
 impl Game<'_> {
    /// Reads `horizon-mods/` and the dev mods, and starts the ones turned on.
    pub(super) fn start_mods(&mut self) {
@@ -237,15 +237,7 @@ impl Game<'_> {
                    let _ = std::fs::create_dir_all(&dir);
                    super::packs::open_folder(&dir);
                }
-                Event::OpenShaderPackFolder => {
-                    let dir = horizon_client::shader_pack::folder();
-                    let _ = std::fs::create_dir_all(&dir);
-                    super::packs::open_folder(&dir);
-                }
                Event::Credits => self.open_win_screen(false, super::win::Finish::Options),
-                Event::ReloadShaderPack => {
-                    self.load_shader_pack();
-                }
            }
        }
        Ok(())
@@ -294,14 +286,6 @@ impl Game<'_> {
            font.reset_cache();
            self.ui.chat.rescale(&self.gui.atlas);
        }
-        // A new renderer (resource reload, first window) takes the loaded pack.
-        let stale = self
-            .renderer
-            .as_ref()
-            .is_some_and(|r| r.shader_pack_id() != self.shader_packs.id());
-        if stale && let Err(e) = self.apply_shader_pack() {
-            log::warn!("Horizon: shader pack: {e}");
-        }
    }
    /// `Window.updateFullscreenState`: a fullscreen change made by the window
    /// system is adopted by the option (`Minecraft.fullscreenStateChanged`).
@@ -4,7 +4,7 @@ use super::Game;
 use horizon_client::{
    hud::HudAtlas,
    lang,
-    pack_screen::{Compat, PackInfo, Source as PackSource},
+    pack_screen::{self, Compat, PackInfo, Source as PackSource},
    packs::{self, Pack, Position},
    text::{Style, Text},
 };
@@ -34,10 +34,16 @@ pub fn open_folder(dir: &Path) {
        log::warn!("Horizon: could not open {}: {e}", dir.display());
    }
 }
-/// The resource root to load from, given the vanilla root and the selection.
-pub fn startup_root(vanilla: &Path, selected: &[String]) -> std::io::Result<PathBuf> {
+/// The resource root to load from, given the vanilla root, the selection and
+/// a server's packs, which go on top (`Pack.Position.TOP`, fixed).
+pub fn startup_root(
+    vanilla: &Path,
+    selected: &[String],
+    server: &[Pack],
+) -> std::io::Result<PathBuf> {
    let all = packs::discover(vanilla, &packs_dir());
-    let enabled = packs::enabled(&all, selected);
+    let mut enabled = packs::enabled(&all, selected);
+    enabled.extend_from_slice(server);
    packs::resource_root(vanilla, &enabled, &cache_dir())
 }
 fn info(p: &Pack) -> PackInfo {
@@ -53,14 +59,15 @@ fn info(p: &Pack) -> PackInfo {
            PackSource::Default
        },
        compat: p.compatibility,
-        icon: p.icon,
+        icon: p.icon_png().as_deref().and_then(pack_screen::load_icon),
        required: false,
        position: Position::Top,
        fixed: false,
    }
 }
-/// The vanilla pack: required, at the bottom (`BuiltInPackSource`).
-fn vanilla_info() -> PackInfo {
+/// The vanilla pack: required, at the bottom (`BuiltInPackSource`), with the
+/// client JAR's `pack.png` that the prepared resources hold.
+fn vanilla_info(vanilla: &Path) -> PackInfo {
    PackInfo {
        id: "vanilla".into(),
        title: Text::translate("resourcePack.vanilla.name", &[]),
@@ -68,7 +75,10 @@ fn vanilla_info() -> PackInfo {
        description_style: Style::default(),
        source: PackSource::BuiltIn,
        compat: Compat::Compatible,
-        icon: true,
+        icon: std::fs::read(vanilla.join("pack.png"))
+            .ok()
+            .as_deref()
+            .and_then(pack_screen::load_icon),
        required: true,
        position: Position::Bottom,
        fixed: false,
@@ -80,7 +90,7 @@ pub(super) fn pack_infos(vanilla: &Path) -> Vec<PackInfo> {
        .iter()
        .map(info)
        .collect();
-    infos.push(vanilla_info());
+    infos.push(vanilla_info(vanilla));
    infos
 }
 impl Game<'_> {
@@ -113,14 +123,7 @@ impl Game<'_> {
            self.pending_pack_reload = true;
            return;
        }
-        let vanilla = self.vanilla_root();
-        if self.ui.vanilla_root.as_os_str().is_empty() {
-            self.ui.vanilla_root = vanilla.clone();
-        }
-        let result = startup_root(&vanilla, &self.settings.resource_packs)
-            .map_err(Into::into)
-            .and_then(|root| self.reload_resources(&root));
-        if let Err(e) = result {
+        if let Err(e) = self.reload_selected_packs() {
            log::warn!("Horizon: resource reload failed: {e}");
            if self.screen != super::Screen::Options {
                self.open_options_at(
@@ -131,6 +134,16 @@ impl Game<'_> {
            self.ui.options.resource_error = Some(e.to_string());
        }
    }
+    /// Reload from the selected packs and the server's.
+    pub(super) fn reload_selected_packs(&mut self) -> horizon_client::Result<()> {
+        let vanilla = self.vanilla_root();
+        if self.ui.vanilla_root.as_os_str().is_empty() {
+            self.ui.vanilla_root = vanilla.clone();
+        }
+        let server = &self.server_packs.active;
+        let root = startup_root(&vanilla, &self.settings.resource_packs, server)?;
+        self.reload_resources(&root)
+    }
    fn reload_resources(&mut self, root: &Path) -> horizon_client::Result<()> {
        let render = std::sync::Arc::new(self.pack.assets.reload(root)?);
        let mut atlas = HudAtlas::build_over(root, &self.vanilla_root())?;
@@ -38,9 +38,16 @@ impl Game<'_> {
            m.extra.rider = Some(rider);
        }
    }
-    /// Riders sit on their vehicles (`Entity.positionRider`), and let go when
-    /// the vehicle dies or is gone.
+    /// Riders sit on their vehicles (`Entity.positionRider`), mobs or boats,
+    /// and let go when the vehicle dies or is gone.
    pub(super) fn sync_riders(&mut self) {
+        // Entity.baseTick.
+        for m in &mut self.mobs {
+            if m.extra.boarding_cooldown > 0 {
+                m.extra.boarding_cooldown -= 1;
+            }
+        }
+        let boats: std::collections::HashSet<u32> = self.boats.iter().map(|b| b.id).collect();
        let index: HashMap<u32, usize> = self
            .mobs
            .iter()
@@ -54,9 +61,10 @@ impl Game<'_> {
            };
            let valid = self.mobs[i].alive()
                && !self.mobs[i].removed
-                && index
-                    .get(&v)
-                    .is_some_and(|&j| self.mobs[j].alive() && !self.mobs[j].removed);
+                && (boats.contains(&v)
+                    || index
+                        .get(&v)
+                        .is_some_and(|&j| self.mobs[j].alive() && !self.mobs[j].removed));
            if valid {
                riding.insert(v, self.mobs[i].id);
            } else {
@@ -68,6 +76,19 @@ impl Game<'_> {
        for m in &mut self.mobs {
            m.extra.rider = riding.get(&m.id).copied();
        }
+        self.position_riders();
+    }
+    /// `Entity.positionRider` for every mob passenger: in its boat, then on
+    /// its mob. A server's client places them itself too, as the server sends
+    /// no passenger's position.
+    pub(super) fn position_riders(&mut self) {
+        self.seat_boat_mobs();
+        let index: HashMap<u32, usize> = self
+            .mobs
+            .iter()
+            .enumerate()
+            .map(|(i, m)| (m.id, i))
+            .collect();
        // Riders of riders settle over a few passes.
        for _ in 0..3 {
            for i in 0..self.mobs.len() {
@@ -243,6 +243,8 @@ impl Game<'_> {
                        .is_some_and(|(wood, chest)| self.boat_models.has(wood, chest)) =>
                    {
                        if let Some((position, velocity, yaw)) = entity_nbt::boat_from_nbt(&tag) {
+                            let mut tag = tag;
+                            let riders = self.take_mob_passengers(&mut tag);
                            self.next_entity += 1;
                            let id = self.next_entity;
                            let (wood, chest) =
@@ -263,6 +265,9 @@ impl Game<'_> {
                            b.velocity = velocity;
                            self.remember(id, uuid, tag);
                            self.boats.push(b);
+                            for rider in riders {
+                                self.load_mob(rider, Some(id));
+                            }
                        }
                    }
                    k if super::minecarts::CartKind::from_id(k).is_some() => {
@@ -341,25 +346,10 @@ impl Game<'_> {
        // Structure entities placed with finalizeEntities.
        let mut tag = tag;
        let mut finalize = false;
-        let mut riders = Vec::new();
-        let mut unknown = Vec::new();
        if let Tag::Compound(c) = &mut tag {
            finalize = c.remove(&"horizon:finalize".into()).is_some();
-            if let Some(Tag::List(list)) = c.remove(&"Passengers".into()) {
-                for p in list {
-                    let known =
-                        entity_nbt::kind(&p).is_some_and(|k| self.res.mob_types().contains_key(&k));
-                    if known {
-                        riders.push(p);
-                    } else {
-                        unknown.push(p);
-                    }
-                }
-            }
-            if !unknown.is_empty() {
-                c.insert("Passengers".into(), Tag::List(unknown));
-            }
        }
+        let riders = self.take_mob_passengers(&mut tag);
        let mut m = entity_nbt::mob_from_nbt(&tag, self.res.mob_types(), self.next_entity)?;
        m.extra.mount = mount;
        m.extra.passenger = mount.is_some();
@@ -401,6 +391,49 @@ impl Game<'_> {
        }
        Some(id)
    }
+    /// The mobs under an entity's `Passengers`, taken out of it; the
+    /// passengers Horizon doesn't simulate stay.
+    fn take_mob_passengers(&self, tag: &mut Tag) -> Vec<Tag> {
+        let mut riders = Vec::new();
+        if let Tag::Compound(c) = tag
+            && let Some(Tag::List(list)) = c.remove(&"Passengers".into())
+        {
+            let mut unknown = Vec::new();
+            for p in list {
+                let known =
+                    entity_nbt::kind(&p).is_some_and(|k| self.res.mob_types().contains_key(&k));
+                if known {
+                    riders.push(p);
+                } else {
+                    unknown.push(p);
+                }
+            }
+            if !unknown.is_empty() {
+                c.insert("Passengers".into(), Tag::List(unknown));
+            }
+        }
+        riders
+    }
+    /// The mobs riding entity `id` under `tag`'s `Passengers`, after the
+    /// passengers it kept from loading.
+    fn put_mob_passengers(&mut self, tag: &mut Tag, id: u32) {
+        let riders: Vec<usize> = (0..self.mobs.len())
+            .filter(|&j| self.mobs[j].extra.mount == Some(id) && self.mobs[j].alive())
+            .collect();
+        let riders: Vec<Tag> = riders.into_iter().map(|j| self.mob_tree_nbt(j)).collect();
+        if let Tag::Compound(c) = tag {
+            let mut list = match c.get(&"Passengers".into()) {
+                Some(Tag::List(l)) => l.clone(),
+                _ => Vec::new(),
+            };
+            list.extend(riders);
+            if list.is_empty() {
+                c.remove(&"Passengers".into());
+            } else {
+                c.insert("Passengers".into(), Tag::List(list));
+            }
+        }
+    }
    /// An entity of a type Horizon does not simulate, kept as its compound.
    fn load_other(&mut self, tag: Tag, kind: &str) -> Option<u32> {
        let position = entity_nbt::position(&tag)?;
@@ -476,22 +509,7 @@ impl Game<'_> {
        let uuid = self.uuid_for(id);
        let mut tag = entity_nbt::mob_to_nbt(&self.mobs[i], uuid, self.persist.raw.get(&id));
        self.write_leash(&mut tag, i);
-        let riders: Vec<usize> = (0..self.mobs.len())
-            .filter(|&j| self.mobs[j].extra.mount == Some(id) && self.mobs[j].alive())
-            .collect();
-        let riders: Vec<Tag> = riders.into_iter().map(|j| self.mob_tree_nbt(j)).collect();
-        if let Tag::Compound(c) = &mut tag {
-            let mut list = match c.get(&"Passengers".into()) {
-                Some(Tag::List(l)) => l.clone(),
-                _ => Vec::new(),
-            };
-            list.extend(riders);
-            if list.is_empty() {
-                c.remove(&"Passengers".into());
-            } else {
-                c.insert("Passengers".into(), Tag::List(list));
-            }
-        }
+        self.put_mob_passengers(&mut tag, id);
        tag
    }
    /// Forget an entity that left the world (its UUID and loaded compound).
@@ -569,10 +587,15 @@ impl Game<'_> {
        let mut out: HashMap<(i32, i32), Vec<Tag>> =
            keys.iter().map(|k| (*k, Vec::new())).collect();
        let player_uuid = self.level.player_uuid;
-        // A rider is saved inside its root vehicle, in the root's chunk.
+        // A rider is saved inside its root vehicle, in the root's chunk; a
+        // boat's passengers inside the boat.
        let mobs: Vec<usize> = (0..self.mobs.len())
            .filter(|&i| {
                self.mob_root(i) == i
+                    && self.mobs[i]
+                        .extra
+                        .mount
+                        .is_none_or(|v| self.boats.iter().all(|b| b.id != v))
                    && keys.contains(&chunk_of(self.mobs[i].position))
                    && self.mobs[i].alive()
            })
@@ -650,25 +673,29 @@ impl Game<'_> {
                    .push(with_raw(tag, raw.as_ref()));
            }
        }
-        for b in &self.boats {
-            if keys.contains(&chunk_of(b.position)) {
-                let uuid = self
-                    .persist
-                    .uuids
-                    .get(&b.id)
-                    .copied()
-                    .unwrap_or_else(random_uuid);
-                let tag = entity_nbt::boat_to_nbt(
-                    &b.entity_type(),
-                    b.position,
-                    b.velocity,
-                    b.yaw,
-                    uuid,
-                    self.persist.raw.get(&b.id),
-                    b.chest.then_some(&b.items[..]),
-                );
-                out.entry(chunk_of(b.position)).or_default().push(tag);
-            }
+        let boats: Vec<usize> = (0..self.boats.len())
+            .filter(|&i| keys.contains(&chunk_of(self.boats[i].position)))
+            .collect();
+        for i in boats {
+            let b = &self.boats[i];
+            let (id, at) = (b.id, b.position);
+            let uuid = self
+                .persist
+                .uuids
+                .get(&id)
+                .copied()
+                .unwrap_or_else(random_uuid);
+            let mut tag = entity_nbt::boat_to_nbt(
+                &b.entity_type(),
+                b.position,
+                b.velocity,
+                b.yaw,
+                uuid,
+                self.persist.raw.get(&id),
+                b.chest.then_some(&b.items[..]),
+            );
+            self.put_mob_passengers(&mut tag, id);
+            out.entry(chunk_of(at)).or_default().push(tag);
        }
        if let Some(d) = &self.dragon
            && keys.contains(&chunk_of(d.position))
@@ -833,9 +860,16 @@ impl Game<'_> {
                }
                keep
            });
-            // Riders leave with their root vehicle.
+            // Riders leave with their root vehicle, a boat's with the boat.
            let leaving: HashSet<u32> = (0..self.mobs.len())
-                .filter(|&i| gone(self.mobs[self.mob_root(i)].position))
+                .filter(|&i| {
+                    let r = self.mob_root(i);
+                    match self.mobs[r].extra.mount {
+                        Some(v) if removed.contains(&v) => true,
+                        Some(v) if self.boats.iter().any(|b| b.id == v) => false,
+                        _ => gone(self.mobs[r].position),
+                    }
+                })
                .map(|i| self.mobs[i].id)
                .collect();
            self.mobs.retain(|m| {
@@ -140,9 +140,13 @@ pub(super) struct Remote {
    stepped: HashMap<i32, SteppedInterpolation>,
    /// `LivingEntity.lerpHeadTo`: the head yaw and the ticks left to reach it.
    head_lerps: HashMap<i32, (f32, u32)>,
-    /// Item entities waiting for their item data.
-    pending_items: HashMap<i32, [f64; 3]>,
+    /// Item entities waiting for their item data: where they are and their
+    /// motion.
+    pending_items: HashMap<i32, ([f64; 3], Vec3)>,
    health: (f32, i32, f32),
+    /// `LocalPlayer.flashOnSetHealth`: set by the first health the server
+    /// sends; from then on a drop starts the hurt animation.
+    flash_on_set_health: bool,
    game_mode: i32,
    pub chat: Vec<(String, Instant)>,
    /// Lines received since joining, for the control socket's events.
@@ -305,6 +309,16 @@ impl Game<'_> {
        // A signed-in account always plays under its own name.
        let auth = horizon_client::auth::current();
        let name = auth.as_ref().map_or(name, |a| a.name.as_str());
+        let user = auth.as_ref().map_or_else(
+            || {
+                (
+                    name.to_owned(),
+                    horizon_protocol::crypto::offline_uuid(name),
+                )
+            },
+            |a| (a.name.clone(), a.uuid),
+        );
+        self.server_packs_connect(local.is_none().then_some(address), user);
        let session = match local {
            Some(pipe) => Session::connect_local(pipe, name, view, lang.clone()),
            None => {
@@ -401,6 +415,7 @@ impl Game<'_> {
            head_lerps: HashMap::new(),
            pending_items: HashMap::new(),
            health: (20.0, 20, 5.0),
+            flash_on_set_health: false,
            game_mode: 0,
            chat: Vec::new(),
            chat_received: 0,
@@ -453,6 +468,7 @@ impl Game<'_> {
        if let Some(mut r) = self.remote.take() {
            r.session.disconnect();
        }
+        self.server_packs_disconnect();
        // Single player's server thread saves the world before the title shows.
        let single_player = match self.integrated.take() {
            Some(server) => {
@@ -544,7 +560,7 @@ impl Game<'_> {
    /// (`LivingEntity.forceAddEffect`): the effect replaces any of its kind.
    /// Other entities' effects are not shown.
    fn remote_effect(&mut self, p: &play::UpdateMobEffect) {
-        if !self.remote.as_ref().is_some_and(|r| r.entity_id == p.id) {
+        if self.remote.as_ref().is_none_or(|r| r.entity_id != p.id) {
            return;
        }
        let Some(id) = self.remote_effect_id(p.effect) else {
@@ -641,6 +657,22 @@ impl Game<'_> {
                    ("mob_factor", Tag::Float(v[5].to_bits())),
                ]),
                Component::Profile(p) => profile_tag(p),
+                // ItemStackTemplate.CODEC: id, count and components.
+                Component::Stacks(stacks) => Tag::List(
+                    stacks
+                        .iter()
+                        .map(|t| {
+                            let mut entries = vec![
+                                ("id", Tag::String(self.item_name(t.item).as_ref().into())),
+                                ("count", Tag::Int(t.count)),
+                            ];
+                            if let Some(c) = self.protocol_components(t) {
+                                entries.push(("components", c));
+                            }
+                            Tag::compound(entries)
+                        })
+                        .collect(),
+                ),
                Component::CustomModelData {
                    floats,
                    flags,
@@ -811,6 +843,8 @@ impl Game<'_> {
                    }
                }
                Event::Reconfigured(registries) => self.set_registries(registries),
+                Event::PackPush(p) => self.handle_pack_push(p),
+                Event::PackPop(id) => self.handle_pack_pop(id),
                Event::DecodeError(e) => {
                    if let Some(r) = self.remote.as_mut() {
                        r.decode_errors += 1;
@@ -1353,7 +1387,7 @@ impl Game<'_> {
        }
        if let Some(r) = self.remote.as_mut() {
            if kind == "minecraft:item" {
-                r.pending_items.insert(id, position);
+                r.pending_items.insert(id, (position, Vec3::ZERO));
            }
            r.entities.insert(
                id,
@@ -1432,6 +1466,23 @@ impl Game<'_> {
                m.on_ground = on_ground;
                return;
            }
+            if let Some(p) = r.pending_items.get_mut(&id) {
+                p.0 = position;
+            }
+            // ItemEntity and FallingBlockEntity keep Entity's NO_OP
+            // InterpolationHandler: moveOrInterpolateTo puts them there at
+            // once, and their own tick moves them on between the server's
+            // updates (`tick_remote_entities`).
+            let at = Vec3::new(position[0], position[1], position[2]);
+            if let Some(d) = self.dropped.iter_mut().find(|d| d.id == id as u32) {
+                d.position = at;
+                d.on_ground = on_ground;
+                return;
+            }
+            if let Some(f) = self.falling.iter_mut().find(|f| f.id == id as u32) {
+                f.position = at;
+                return;
+            }
            // AbstractInterpolationHandler.interpolateTo: without a rotation,
            // the one it was heading for.
            let rotation = rotation.or_else(|| r.lerps.get(&id).and_then(|l| l.rotation));
@@ -1443,9 +1494,6 @@ impl Game<'_> {
                    steps: 3,
                },
            );
-            if let Some(p) = r.pending_items.get_mut(&id) {
-                *p = position;
-            }
        }
        self.turn_remote_object(id, rotation.map(|(yaw, _)| yaw), on_ground);
        self.turn_remote_projectile(id, rotation);
@@ -1778,6 +1826,8 @@ impl Game<'_> {
                    }
                }
                self.spawn_entity(p.id, &kind, p.position, rotation);
+                // Entity.recreateFromPacket: setDeltaMovement(packet.getMovement()).
+                self.remote_motion(p.id, p.velocity);
                if !self.spawn_remote_object(p.id, &kind, p.position, rotation[0], p.data) {
                    self.spawn_remote_projectile(
                        p.id,
@@ -1974,6 +2024,15 @@ impl Game<'_> {
                                }
                                self.sleeping = *bed;
                            }
+                            // Entity.DATA_SHARED_FLAGS_ID's sprinting bit: the
+                            // server stops the sprint after a hit's extra
+                            // knockback (the flag only, as assignValues sets
+                            // it: the speed modifier and wasSprinting stay).
+                            (0, Value::Byte(flags)) => {
+                                if let Some(pl) = self.player.as_mut() {
+                                    pl.sprinting = flags & 0x08 != 0;
+                                }
+                            }
                            // Entity.DATA_AIR_SUPPLY_ID and
                            // Player.DATA_PLAYER_ABSORPTION_ID: the bubbles
                            // and golden hearts the server's player has.
@@ -2087,17 +2146,29 @@ impl Game<'_> {
                    pl.velocity = Vec3::new(p.velocity[0], p.velocity[1], p.velocity[2]);
                }
            }
+            // The same packet for another entity: Entity.lerpMotion.
+            C::SetEntityMotion(p) => self.remote_motion(p.id, p.velocity),
            // ClientPacketListener.handleDamageEvent: LivingEntity.handleDamageEvent
            // jolts the walk animation and restarts the hurt flash. Its hurt
            // sound comes as a sound from Horizon's host, which plays it itself.
+            // This player's own hurt tilt and flash come from the server too
+            // (sent to the player itself): its own moves never hurt it.
            C::DamageEvent(p) => {
-                if let Some(m) = self.mobs.iter_mut().find(|m| m.id == p.id as u32) {
+                if self.remote.as_ref().is_some_and(|r| r.entity_id == p.id) {
+                    if let Some(pl) = self.player.as_mut() {
+                        pl.health.animate_hurt();
+                    }
+                } else if let Some(m) = self.mobs.iter_mut().find(|m| m.id == p.id as u32) {
                    m.limb_speed = 1.5;
                    m.hurt_time = 10;
                }
            }
            C::HurtAnimation(p) => {
-                if let Some(m) = self.mobs.iter_mut().find(|m| m.id == p.id as u32) {
+                if self.remote.as_ref().is_some_and(|r| r.entity_id == p.id) {
+                    if let Some(pl) = self.player.as_mut() {
+                        pl.health.animate_hurt();
+                    }
+                } else if let Some(m) = self.mobs.iter_mut().find(|m| m.id == p.id as u32) {
                    m.hurt_time = 10;
                }
            }
@@ -2163,9 +2234,14 @@ impl Game<'_> {
                self.remote_world_options_difficulty(self.ui.difficulty, p.locked);
            }
            C::GameRuleValues(p) => self.remote_world_options_rules(p.entries),
+            // ClientPacketListener.handleSetHealth: LocalPlayer.hurtTo.
            C::SetHealth(p) => {
-                if let Some(r) = self.remote.as_mut() {
+                let flash = self.remote.as_mut().is_some_and(|r| {
                    r.health = (p.health, p.food, p.saturation);
+                    std::mem::replace(&mut r.flash_on_set_health, true)
+                });
+                if flash && let Some(pl) = self.player.as_mut() {
+                    pl.health.flash_health_change(p.health);
                }
                self.apply_remote_health();
                if p.health <= 0.0 && self.screen != Screen::Dead && self.player.is_some() {
@@ -2557,6 +2633,8 @@ impl Game<'_> {
                self.drop_remote_chunks_out_of_range();
            }
            C::BlockEntityData(p) => self.remote_block_entity_data(p.pos, p.kind, &p.tag),
+            C::OpenSignEditor(p) => self.remote_open_sign_editor(p),
+            C::OpenBook(p) => self.remote_open_book(p.hand),
            // handleSetSpawn: ClientLevel.setRespawnData, which spawn compasses point at.
            C::SetDefaultSpawnPosition(p) => {
                let [x, y, z] = p.pos.pos;
@@ -2893,7 +2971,9 @@ impl Game<'_> {
            item.stack = stack;
            return;
        }
-        let Some(p) = position else { return };
+        let Some((p, velocity)) = position else {
+            return;
+        };
        let at = Vec3::new(p[0], p[1], p[2]);
        let bob_offset = self.world.random.next_float() * std::f32::consts::PI * 2.0;
        self.dropped.push(ItemEntity {
@@ -2904,7 +2984,7 @@ impl Game<'_> {
            stack,
            position: at,
            previous: at,
-            velocity: Vec3::ZERO,
+            velocity,
            on_ground: false,
            age: 0,
            pickup_delay: 0,
@@ -2912,6 +2992,23 @@ impl Game<'_> {
            ticks: 0,
        });
    }
+    /// `Entity.lerpMotion` (and `recreateFromPacket`'s motion) for the
+    /// entities whose own tick moves them on a client: dropped items and
+    /// falling blocks.
+    fn remote_motion(&mut self, id: i32, velocity: [f64; 3]) {
+        let v = Vec3::new(velocity[0], velocity[1], velocity[2]);
+        if let Some(d) = self.dropped.iter_mut().find(|d| d.id == id as u32) {
+            d.velocity = v;
+        } else if let Some(f) = self.falling.iter_mut().find(|f| f.id == id as u32) {
+            f.velocity = v;
+        } else if let Some(p) = self
+            .remote
+            .as_mut()
+            .and_then(|r| r.pending_items.get_mut(&id))
+        {
+            p.1 = v;
+        }
+    }
    fn apply_remote_health(&mut self) {
        let Some((health, food, saturation)) = self.remote.as_ref().map(|r| r.health) else {
            return;
@@ -3054,7 +3151,7 @@ impl Game<'_> {
        self.sleep_timer = super::tick_sleep_timer(self.sleep_timer, self.sleeping.is_some());
        // Gui.tick: the titles, the action bar and the held item's name.
        self.tick_hud();
-        let ghast_collisions = self.happy_ghast_player_collisions();
+        let entity_collisions = self.player_entity_collisions();
        let pushed = self.remote_pushes();
        let Some(player) = self.player.as_mut() else {
            return Ok(());
@@ -3109,6 +3206,9 @@ impl Game<'_> {
            | u8::from(keys.sprint) << 6;
        // A passenger moves with its vehicle (Entity.rideTick), not by itself.
        let riding = self.screen != Screen::Dead && self.remote_ride(keys);
+        // The server sends no passenger's position: they sit where their
+        // vehicles are now.
+        self.position_riders();
        let Some(player) = self.player.as_mut() else {
            return Ok(());
        };
@@ -3121,14 +3221,11 @@ impl Game<'_> {
            [player.position.x, player.position.y, player.position.z],
        );
        let was_flying = player.flying;
-        player.yaw = self.yaw;
-        // As the window's own tick has them: the helmet's Respiration
-        // (decreaseAirSupply) and the dimension's FAST_LAVA, the Nether's
-        // stronger lava current.
-        player.respiration = self.armor[0]
-            .as_ref()
-            .map_or(0, |s| s.enchantment_level("minecraft:respiration") as i32);
-        player.fluids.fast_lava = self.dim == Dim::Nether;
+        self.sync_player_body();
+        let Some(player) = self.player.as_mut() else {
+            return Ok(());
+        };
+        let was_gliding = player.fall_flying;
        let dead = self.screen == Screen::Dead;
        // LivingEntity.isImmobile: a sleeper lies still in the bed.
        if let Some(head) = self.sleeping {
@@ -3139,9 +3236,10 @@ impl Game<'_> {
            );
            player.velocity = Vec3::ZERO;
        } else if !dead && !riding {
+            player.client_side = true;
            player.velocity = player.velocity.add_vector(pushed);
            MotionWorld {
-                entities: &ghast_collisions,
+                entities: &entity_collisions,
                player,
                scene: &mut self.world,
                assets: &self.pack.assets,
@@ -3153,6 +3251,9 @@ impl Game<'_> {
        // LocalPlayer.onUpdateAbilities: flight turned on or off (a double
        // jump, a spectator, landing) is sent to the server.
        let flying = player.flying;
+        // LocalPlayer.aiStep: a glide this client started is sent to the
+        // server (ServerboundPlayerCommandPacket START_FALL_FLYING).
+        let started_gliding = player.fall_flying && !was_gliding;
        let events = std::mem::take(&mut player.events);
        self.previous_eye = self.eye;
        self.eye += (player.dimensions.eye_height - self.eye) * 0.5;
@@ -3179,7 +3280,7 @@ impl Game<'_> {
                _ => {}
            }
        }
-        // The server owns health and hunger: undo local food/fall changes.
+        // The server owns health and hunger.
        self.apply_remote_health();
        self.tick_avatar(before, false);
        // The player's own model (third person, the inventory's preview).
@@ -3192,6 +3293,14 @@ impl Game<'_> {
                flags: if flying { 2 } else { 0 },
            }));
        }
+        if started_gliding {
+            let id = self.remote.as_ref().map_or(0, |r| r.entity_id);
+            self.send(S::PlayerCommand(play::PlayerCommand {
+                id,
+                action: 6,
+                data: 0,
+            }));
+        }
        self.remote_send_state(input);
        Ok(())
    }
@@ -3211,9 +3320,10 @@ impl Game<'_> {
        player.flying_speed = a.flying_speed;
    }
    /// The local player's share of every touching entity's
-    /// `LivingEntity.pushEntities`: on a client `EntitySelector.pushableBy`
-    /// lets entities push only the local player, so the server never sends
-    /// these pushes. `doPush(player)` is `player.push(entity)`.
+    /// `LivingEntity.pushEntities`, and of the boats' pushes: on a client
+    /// `EntitySelector.pushableBy` lets entities push only the local player,
+    /// so the server never sends these pushes. `doPush(player)` is
+    /// `player.push(entity)`.
    fn remote_pushes(&self) -> Vec3 {
        let (Some(p), Some(r)) = (self.player.as_ref(), self.remote.as_ref()) else {
            return Vec3::ZERO;
@@ -3272,11 +3382,51 @@ impl Game<'_> {
            za *= f64::from(0.05_f32);
            push = Vec3::new(push.x - xa, push.y, push.z - za);
        }
+        // AbstractBoat.push(player) from the boat's own tick (its box grown
+        // by 0.2 sideways) and from the player's pushEntities (its box).
+        let player_team = teams.of(Who::Player);
+        let area = Vec3::new(f64::from(0.2_f32), f64::from(-0.01_f32), f64::from(0.2_f32));
+        for b in self.boats.iter().filter(|b| self.riding != Some(b.id)) {
+            let bb = b.bounds();
+            let times = usize::from(
+                bounds.intersects(bb.inflate(area))
+                    && horizon_client::scoreboard::pushable_by(None, player_team, true),
+            ) + usize::from(
+                bounds.intersects(bb)
+                    && horizon_client::scoreboard::pushable_by(player_team, None, true),
+            );
+            if times > 0
+                && super::boat_passengers::boat_pushes(bb, bounds, false)
+                && let Some(v) = super::boat_passengers::push_impulse(b.position, p.position)
+            {
+                push = push.add_vector(v.scale(times as f64));
+            }
+        }
        push
    }
    /// ClientLevel.tickEntities; a frozen level only ticks the players
    /// (`TickRateManager.isEntityFrozen`).
    fn tick_remote_entities(&mut self, running: bool) {
+        // EntityFluidInteraction.update for the entities this window only displays: the
+        // server never sends the fluid contact, and the renderers read it (cod, salmon and
+        // tropical fish lie on their side without `in_water`, #1591).
+        // A frozen level ticks only the players, as below.
+        let fluids: Vec<_> = {
+            let w = self.mob_world_base(&[]);
+            let players = self.remote.as_ref().map(|r| &r.level_players);
+            self.mobs
+                .iter()
+                .map(|m| {
+                    (running || players.is_some_and(|p| p.contains_key(&(m.id as i32))))
+                        .then(|| w.fluids(m.bounds(), m.eye_y()))
+                })
+                .collect()
+        };
+        for (m, fluids) in self.mobs.iter_mut().zip(fluids) {
+            if let Some(fluids) = fluids {
+                m.fluids = fluids;
+            }
+        }
        let Some(r) = self.remote.as_mut() else {
            return;
        };
@@ -3379,20 +3529,12 @@ impl Game<'_> {
                l.steps -= 1;
            }
        }
+        // ItemEntity.tick runs on a client too: gravity, collisions and
+        // friction move the item between the server's updates (every 20
+        // ticks), and only the server removes it.
+        let (world, facts, collision) = (&self.world, self.res.facts(), self.collision);
        for d in self.dropped.iter_mut().filter(|_| running) {
-            d.previous = d.position;
-            d.age += 1;
-            if let Some(l) = lerps.get_mut(&(d.id as i32))
-                && l.steps > 0
-            {
-                let n = f64::from(l.steps);
-                d.position = Vec3::new(
-                    d.position.x + (l.target[0] - d.position.x) / n,
-                    d.position.y + (l.target[1] - d.position.y) / n,
-                    d.position.z + (l.target[2] - d.position.z) / n,
-                );
-                l.steps -= 1;
-            }
+            d.tick(world, facts, collision, false);
        }
        head_lerps.retain(|_, (_, steps)| *steps > 0);
        for (item, ticks, at, eye, pitch, yaw) in using {
@@ -4010,21 +4152,60 @@ impl Game<'_> {
            return false;
        };
        // MultiPlayerGameMode.useItem runs the use here too: food starts
-        // being eaten (Consumable.startConsuming).
+        // being eaten (Consumable.startConsuming), a book and quill opens.
        self.with_hand(hand, |g| g.start_eating(&info));
-        // BowItem.use: startUsingItem here too (with an arrow, or in creative), so that letting
-        // go sends RELEASE_USE_ITEM (Minecraft.handleKeybinds) and the server shoots.
-        if &*held.item == "minecraft:bow" {
-            self.with_hand(hand, |g| {
-                if g.using.is_none() && (g.creative || g.projectile_slot("minecraft:bow").is_some())
-                {
-                    g.using = Some((g.held_slot(), 0));
-                }
-            });
+        if self.with_hand(hand, |g| g.remote_use_book(&held)) {
+            return true;
        }
+        self.with_hand(hand, |g| g.remote_start_held_use(&held));
        item_has_use(&info)
    }

+    /// `Item.use` runs on the client too (MultiPlayerGameMode.useItem): an
+    /// item held in use until the button lets go starts being used here, so
+    /// that letting go sends RELEASE_USE_ITEM (Minecraft.handleKeybinds) and
+    /// the server ends the use: a bow or a trident is let go, a crossbow's
+    /// charge ends, a shield is lowered, a spyglass stops scoping. Their
+    /// sounds, loaded arrows and thrown tridents come from the server.
+    fn remote_start_held_use(&mut self, held: &ItemStack) {
+        if self.using.is_some() {
+            return;
+        }
+        let start = match &*held.item {
+            // BowItem.use: with an arrow, or in creative.
+            "minecraft:bow" => self.creative || self.projectile_slot("minecraft:bow").is_some(),
+            // CrossbowItem.use: charging when not charged and with ammunition;
+            // a charged one shoots on the server.
+            "minecraft:crossbow" => {
+                held.data().is_none_or(|d| d.charged.is_empty())
+                    && (self.creative || self.projectile_slot("minecraft:crossbow").is_some())
+            }
+            // TridentItem.use: not about to break, Riptide only in water or rain.
+            "minecraft:trident" => {
+                self.use_trident(held);
+                return;
+            }
+            // SpyglassItem.use (its sound is the server's).
+            "minecraft:spyglass" => true,
+            // ShieldItem.use: anything that blocks attacks, off cooldown.
+            _ => {
+                self.raise_shield(self.held_slot());
+                return;
+            }
+        };
+        if start {
+            self.using = Some((self.held_slot(), 0));
+        }
+    }
+    /// Whether `stack` stays in use until the button lets go (bows,
+    /// crossbows, tridents, spyglasses, shields): its use only counts ticks here.
+    fn held_until_released(&self, stack: &ItemStack) -> bool {
+        matches!(
+            &*stack.item,
+            "minecraft:bow" | "minecraft:crossbow" | "minecraft:trident" | "minecraft:spyglass"
+        ) || self.blocks_attacks(stack).is_some()
+    }
+
    /// The rest of Minecraft.startUseItem once the main hand's target passed:
    /// the main hand's item, then the off hand's turn (its block, its item).
    /// The server does each packet's part with that packet's hand only.
@@ -4043,7 +4224,8 @@ impl Game<'_> {
        }
        self.remote_use_item(Hand::Off);
    }
-    /// `LivingEntity.updatingUsingItem` on a server client: a drawn bow, and a
+    /// `LivingEntity.updatingUsingItem` on a server client: an item held in
+    /// use (`held_until_released`), and a
    /// consumable's eating animation and its crumbs. The server eats it and
    /// sends the stack, the hunger and the sounds.
    fn remote_tick_using(&mut self) {
@@ -4051,8 +4233,9 @@ impl Game<'_> {
            return;
        };
        let stack = self.stack_in(slot).cloned();
-        // A drawn bow: held until the button lets go (or another slot is picked).
-        if stack.as_ref().is_some_and(|s| &*s.item == "minecraft:bow") {
+        // A drawn bow, a charging crossbow, a raised shield...: held until
+        // the button lets go (or another slot is picked).
+        if stack.as_ref().is_some_and(|s| self.held_until_released(s)) {
            self.using = (slot == self.selected || slot == super::shield::OFFHAND_SLOT)
                .then_some((slot, ticks + 1));
            return;
@@ -4242,8 +4425,7 @@ impl Game<'_> {
    /// Keys with a multiplayer meaning; returns true when consumed.
    pub(super) fn remote_key(&mut self, key: KeyCode) -> Result<bool> {
        if self.screen != Screen::Playing {
-            if key == KeyCode::KeyE && self.screen == Screen::Inventory
-                || key == KeyCode::Escape && self.screen == Screen::Inventory
+            if (key == KeyCode::KeyE || key == KeyCode::Escape) && self.screen == Screen::Inventory
            {
                self.remote_close_container();
                self.screen = Screen::Playing;
@@ -3,12 +3,15 @@
 //! `onSyncedDataUpdated`): what a client draws from it rather than from its
 //! own simulation, which a client of a server doesn't run.
 use super::Game;
+use horizon_client::mobs::render::{PROFESSIONS, VILLAGER_TYPES};
 use horizon_client::mobs::{Mob, Species, tame};
 use horizon_protocol::entity_data::Value;
+use horizon_protocol::registry::Builtin;

 /// The values `apply` takes from one SetEntityData packet, by vanilla's entry
 /// indices (Entity 0..=7, LivingEntity 8..=14, Mob 15, then the subclasses).
-fn apply(m: &mut Mob, values: &[(u8, i32, Value)]) {
+/// `builtin` names the ids of built-in registries.
+fn apply(m: &mut Mob, values: &[(u8, i32, Value)], builtin: &Builtin) {
    let species = m.species();
    let baby = super::lan::baby_index(&m.kind.id);
    for (index, _, value) in values {
@@ -42,16 +45,45 @@ fn apply(m: &mut Mob, values: &[(u8, i32, Value)]) {
            (Species::Slime | Species::MagmaCube, 18, Value::Int(size)) => {
                m.extra.size = (*size).clamp(1, 127);
            }
+            // Villager.DATA_VILLAGER_DATA and ZombieVillager's (after
+            // Zombie's three): what VillagerProfessionLayer draws.
+            (Species::Villager, 19, Value::Ids(data))
+            | (Species::ZombieVillager, 20, Value::Ids(data)) => villager_data(m, data, builtin),
            _ => {}
        }
    }
 }

+/// VillagerData as the network sends it: the type and the profession by
+/// their built-in registry ids, then the level.
+fn villager_data(m: &mut Mob, data: &[i32], builtin: &Builtin) {
+    let &[kind, profession, level] = data else {
+        return;
+    };
+    let index = |registry: &str, id: i32, names: &[&str]| {
+        let name = builtin
+            .get(registry)?
+            .name(id)?
+            .strip_prefix("minecraft:")?;
+        names.iter().position(|n| *n == name).map(|i| i as u8)
+    };
+    if let Some(t) = index("minecraft:villager_type", kind, &VILLAGER_TYPES) {
+        m.extra.variant = t;
+    }
+    if let Some(p) = index("minecraft:villager_profession", profession, &PROFESSIONS) {
+        m.extra.variant2 = p;
+    }
+    m.extra.variant3 = level.clamp(0, i32::from(u8::MAX)) as u8;
+}
+
 impl Game<'_> {
    /// SetEntityData for a mob of the server's.
    pub(super) fn remote_mob_data(&mut self, id: i32, values: &[(u8, i32, Value)]) {
+        let Some(r) = &self.remote else {
+            return;
+        };
        if let Some(m) = self.mobs.iter_mut().find(|m| m.id == id as u32) {
-            apply(m, values);
+            apply(m, values, &r.builtin);
        }
    }
 }
@@ -72,11 +104,23 @@ mod tests {

    /// A mob of the prepared resources' type `kind`, as a client spawns it
    /// (None without the resources).
-    fn mob(kind: &str) -> Option<Mob> {
-        let root = std::path::Path::new(env!("CARGO_MANIFEST_DIR"))
+    fn root() -> std::path::PathBuf {
+        std::path::Path::new(env!("CARGO_MANIFEST_DIR"))
            .join("../../.local/horizon-client")
-            .join(horizon_core::VANILLA_VERSION);
-        let types = horizon_client::mobs::MobTypes::load(&root).ok()?;
+            .join(horizon_core::VANILLA_VERSION)
+    }
+
+    /// The prepared resources' built-in registries (empty without them).
+    fn builtin() -> Builtin {
+        Builtin::load(&root().join("registries.json")).unwrap_or_default()
+    }
+
+    fn apply(m: &mut Mob, values: &[(u8, i32, Value)]) {
+        super::apply(m, values, &builtin());
+    }
+
+    fn mob(kind: &str) -> Option<Mob> {
+        let types = horizon_client::mobs::MobTypes::load(&root()).ok()?;
        let t = std::sync::Arc::new(types.types.get(kind)?.clone());
        let mut m = Mob::new(1, t, horizon_core::geometry::Vec3::ZERO, 0.0);
        client_defaults(&mut m);
@@ -133,4 +177,45 @@ mod tests {
        apply(&mut m, &[(0, s::BYTE, Value::Byte(0))]);
        assert_eq!(m.fire_ticks, 0);
    }
+
+    #[test]
+    fn a_villager_takes_its_type_profession_and_level() {
+        let Some(mut m) = mob("minecraft:villager") else {
+            return;
+        };
+        let registries = builtin();
+        let id = |registry: &str, name: &str| registries.get(registry)?.id(name);
+        let (Some(desert), Some(farmer), Some(librarian)) = (
+            id("minecraft:villager_type", "minecraft:desert"),
+            id("minecraft:villager_profession", "minecraft:farmer"),
+            id("minecraft:villager_profession", "minecraft:librarian"),
+        ) else {
+            return;
+        };
+        let name = |m: &Mob| {
+            (
+                VILLAGER_TYPES[m.extra.variant as usize],
+                PROFESSIONS[m.extra.variant2 as usize],
+                m.extra.variant3,
+            )
+        };
+        apply(
+            &mut m,
+            &[(19, s::VILLAGER_DATA, Value::Ids(vec![desert, farmer, 2]))],
+        );
+        assert_eq!(name(&m), ("desert", "farmer", 2));
+        // A job taken later: only the profession and the level change.
+        apply(
+            &mut m,
+            &[(19, s::VILLAGER_DATA, Value::Ids(vec![desert, librarian, 5]))],
+        );
+        assert_eq!(name(&m), ("desert", "librarian", 5));
+        // A zombie villager's data comes after Zombie's three entries.
+        let mut z = mob("minecraft:zombie_villager").unwrap();
+        apply(
+            &mut z,
+            &[(20, s::VILLAGER_DATA, Value::Ids(vec![desert, farmer, 3]))],
+        );
+        assert_eq!(name(&z), ("desert", "farmer", 3));
+    }
 }
@@ -2,7 +2,7 @@
 //! end crystals on a server's client (`ClientPacketListener.handleAddEntity`
 //! and `handleSetEntityData`): the server simulates them, the client draws
 //! them where it says and interpolates their moves.
-use super::{FallingBlock, Game};
+use super::{FallStep, FallingBlock, Game};
 use horizon_client::projectiles::{Projectile, ProjectileKind};
 use horizon_core::{geometry::Vec3, position::BlockPos};
 use horizon_protocol::entity_data::Value;
@@ -88,6 +88,8 @@ impl Game<'_> {
                self.end
                    .add_remote_eye(id, position, [velocity.x, velocity.y, velocity.z])
            }
+            // FishingHook.recreateFromPacket: the owner's id is the data.
+            "minecraft:fishing_bobber" => self.spawn_remote_hook(id, at, data),
            "minecraft:end_crystal" => self.crystals.push(super::dragon::Crystal {
                id,
                position: at,
@@ -114,6 +116,7 @@ impl Game<'_> {
    /// `handleSetEntityData` for these types: what changes how they look.
    pub(super) fn remote_projectile_data(&mut self, id: i32, values: &[(u8, i32, Value)]) {
        let id = id as u32;
+        self.remote_hook_data(id, values);
        if self.potions.has_thrown(id) {
            // ThrowableItemProjectile.DATA_ITEM_STACK: the potion it is.
            for (index, _, value) in values {
@@ -182,11 +185,17 @@ impl Game<'_> {
            t.previous = t.position;
            t.position = step(t.id, t.position);
        }
-        for f in &mut self.falling {
-            f.previous = f.position;
-            f.age += 1;
-            f.position = step(f.id, f.position);
+        // FallingBlockEntity.tick runs on a client too: the block falls by
+        // itself between the server's updates (every 20 ticks), then waits
+        // where it lands for the server to place it and remove it.
+        let mut falling = std::mem::take(&mut self.falling);
+        for f in &mut falling {
+            if let Ok(FallStep::Landed(_)) = self.fall_step(f, false) {
+                // Block.updateEntityMovementAfterFallOn, then the air drag.
+                f.velocity = Vec3::new(f.velocity.x * 0.98, 0.0, f.velocity.z * 0.98);
+            }
        }
+        self.falling = falling;
        for p in &mut self.creatures.projectiles {
            p.previous = p.position;
            p.age += 1;
@@ -205,6 +214,7 @@ impl Game<'_> {
            c.position = step(c.id, c.position);
        }
        self.potions.step_remote_thrown(&mut step);
+        self.step_remote_hooks(&mut step);
        self.end.step_remote_eyes(|id, at| {
            let at = step(id, Vec3::new(at[0], at[1], at[2]));
            [at.x, at.y, at.z]
@@ -220,6 +230,7 @@ impl Game<'_> {
        self.crystals.retain(|c| c.id != id);
        self.potions.remove_remote_thrown(id);
        self.end.remove_remote_eye(id);
+        self.remove_remote_hook(id);
    }

    /// Every one a server sent (a new connection, level or dimension).
@@ -232,6 +243,7 @@ impl Game<'_> {
        self.crystals.clear();
        self.potions.clear_thrown();
        self.end.clear_remote_eyes();
+        self.clear_remote_hooks();
    }

    /// Their kind and place, for `status`.
@@ -260,6 +272,7 @@ impl Game<'_> {
        for (id, p) in self.end.eye_positions() {
            out.push(json!({"id": id, "kind": "minecraft:eye_of_ender", "position": p}));
        }
+        out.extend(self.hooks_status());
        out
    }
 }
@@ -88,8 +88,10 @@ impl Game<'_> {
        for m in &mut self.mobs {
            if m.extra.mount == Some(vehicle_id) && !passengers.contains(&(m.id as i32)) {
                m.extra.mount = None;
+                m.extra.passenger = false;
            } else if passengers.contains(&(m.id as i32)) {
                m.extra.mount = Some(vehicle_id);
+                m.extra.passenger = true;
            }
        }
        if passengers.contains(&me) {
@@ -129,17 +131,20 @@ impl Game<'_> {
            self.yaw += b.delta_rotation;
            let delta = (self.yaw - b.yaw + 180.0).rem_euclid(360.0) - 180.0;
            self.yaw += delta.clamp(-105.0, 105.0) - delta;
-            let seat = b.position;
            self.boats[i] = b;
-            Some(seat)
+            // In front of a mob that shares the boat.
+            Some(self.player_boat_seat(i))
        } else {
            // A minecart: the server moves it, the rider sits in it.
-            self.carts.iter().find(|c| c.id == id).map(|c| c.position)
+            self.carts.iter().find(|c| c.id == id).map(|c| {
+                c.position
+                    .add_vector(Vec3::new(0.0, super::minecarts::SEAT, 0.0))
+            })
        };
        if let Some(p) = self.player.as_mut() {
            self.previous_position = p.position;
            if let Some(v) = seat {
-                p.position = Vec3::new(v.x, v.y + super::boats::SEAT, v.z);
+                p.position = v;
            }
            p.velocity = Vec3::ZERO;
            p.fall_distance = 0.0;
@@ -104,45 +104,6 @@ impl Game<'_> {
            },
        )
    }
-    /// What a shader pack's `Frame` uniform reads of the game this frame.
-    pub(super) fn shader_inputs(
-        &self,
-        camera: glam::DVec3,
-        partial_tick: f32,
-    ) -> horizon_client::gfx::ShaderInputs {
-        let (rain, thunder) = if self.dim == Dim::Overworld {
-            self.world.weather.levels(self.clock.fraction() as f32)
-        } else {
-            (0.0, 0.0)
-        };
-        let at = [camera.x, camera.y, camera.z];
-        let day = self.world.day_time;
-        let has_sky_light = self.dim == Dim::Overworld;
-        // CommonUniforms.getEyeBrightness: the camera entity's eye block.
-        let eye = self.eye_position().unwrap_or(at).map(|v| v.floor() as i32);
-        let light = self.world.light(eye[0], eye[1], eye[2]);
-        let eye_light = [light & 15, if has_sky_light { light >> 4 } else { 0 }];
-        horizon_client::gfx::ShaderInputs {
-            rain,
-            thunder,
-            submerged: match fog_type(&self.world, self.res.facts(), at, self.forward()) {
-                FogType::Atmospheric => 0,
-                FogType::Water => 1,
-                FogType::Lava => 2,
-                FogType::PowderSnow => 3,
-            },
-            dimension: match self.dim {
-                Dim::Overworld => 0,
-                Dim::Nether => -1,
-                Dim::End => 1,
-            },
-            has_sky_light,
-            moon_phase: day.div_euclid(24_000).rem_euclid(8) as u8,
-            day_fraction: (day.rem_euclid(24_000) as f32 + partial_tick) / 24_000.0,
-            partial_tick,
-            eye_light,
-        }
-    }
    /// `SkyRenderer.shouldRenderDarkDisc`: eye below the horizon (y 63) and not under water.
    pub(super) fn dark_disc(&self, camera: glam::DVec3) -> bool {
        camera.y < 63.0
@@ -1054,6 +1054,7 @@ impl Game<'_> {
            let r = &mut self.world.random;
            let bonus = r.triangle(0.0, 0.11485000000000001);
            mob.attrs.follow_range += mob.kind.follow_range * bonus;
+            mob.update_max_visited_nodes();
            let _left_handed = r.next_float() < 0.05;
            if !self.warden_fits(&mob) {
                continue;
@@ -0,0 +1,316 @@
+//! A server's resource packs bound to the game (`ClientCommonPacketListenerImpl.
+//! handleResourcePackPush` and `handleResourcePackPop`, its `PackConfirmScreen`,
+//! and `DownloadedPackSource` as `Minecraft` drives it): the prompt, the
+//! server list's setting, downloads into `downloads/`, and a resource reload
+//! with the server's packs on top of the player's own.
+use super::Game;
+use horizon_client::{
+    Result,
+    confirm_screen::Confirm,
+    hud::{HudAtlas, HudBatch},
+    multiplayer, packs,
+    scoreboard::{comp_text, tag_to_json},
+    server_packs::{Prompt, ServerPacks, action, download, parse_sha1, valid_url},
+    text::{Text, named_color},
+    ui,
+};
+use horizon_protocol::{packets::configuration::ResourcePackPush, servers};
+use std::path::PathBuf;
+
+/// `ClientCommonPacketListenerImpl.PackConfirmScreen`: the packs it asks
+/// about, whether the last one is required, and the server's message.
+pub(super) struct PackPrompt {
+    requests: Vec<(u128, String, String)>,
+    required: bool,
+    prompt: Option<Text>,
+}
+impl PackPrompt {
+    fn texts(&self) -> (Text, Text, [Text; 2]) {
+        let t = |key: &str| Text::translate(key, &[]);
+        let (title, line2) = if self.required {
+            let yellow = named_color("yellow").unwrap_or(0xFFFF55);
+            (
+                t("multiplayer.requiredTexturePrompt.line1"),
+                t("multiplayer.requiredTexturePrompt.line2")
+                    .with_color(yellow)
+                    .bold(),
+            )
+        } else {
+            (
+                t("multiplayer.texturePrompt.line1"),
+                t("multiplayer.texturePrompt.line2"),
+            )
+        };
+        // preparePackPrompt.
+        let message = match &self.prompt {
+            Some(prompt) => Text::translate(
+                "multiplayer.texturePrompt.serverPrompt",
+                &[line2, prompt.clone()],
+            ),
+            None => line2,
+        };
+        let buttons = if self.required {
+            [t("gui.proceed"), t("menu.disconnect")]
+        } else {
+            [t("gui.yes"), t("gui.no")]
+        };
+        (title, message, buttons)
+    }
+    fn layout(&self, atlas: &HudAtlas, size: (f32, f32)) -> Confirm {
+        let (title, message, _) = self.texts();
+        Confirm::new(&atlas.font, size, &title, &message)
+    }
+}
+
+/// The game's `DownloadedPackSource`.
+#[derive(Default)]
+pub(super) struct ServerPackState {
+    packs: ServerPacks,
+    /// `downloads/` in the game folder, opened at the first download.
+    queue: Option<download::Queue>,
+    pub(super) prompt: Option<PackPrompt>,
+    /// The server list entry the setting is saved to (none: a direct join).
+    address: Option<String>,
+    /// The account the downloads are made for (the download headers).
+    user: (String, u128),
+    /// The packs loaded on top of the player's own, bottom first.
+    pub(super) active: Vec<packs::Pack>,
+}
+
+fn saves() -> PathBuf {
+    std::env::current_dir().unwrap_or_default().join("saves")
+}
+
+impl Game<'_> {
+    /// `ConnectScreen`: the server's setting decides what its packs do
+    /// (`configureForServerControl`); single player's own server takes them
+    /// all, quietly (`configureForLocalWorld`).
+    pub(super) fn server_packs_connect(&mut self, address: Option<&str>, user: (String, u128)) {
+        let state = &mut self.server_packs;
+        state.user = user;
+        state.prompt = None;
+        let Some(address) = address else {
+            state.address = None;
+            state.packs.local_world();
+            return;
+        };
+        let file = multiplayer::servers_file(&saves());
+        let entry = servers::load(&file).into_iter().find(|s| s.ip == address);
+        let setting = entry.as_ref().and_then(|e| e.accept_textures);
+        state.address = entry.map(|e| e.ip);
+        state.packs.connect(Prompt::for_server(setting));
+    }
+    /// `Minecraft.clearDownloadedResourcePacks`: every server pack goes at once.
+    pub(super) fn server_packs_disconnect(&mut self) {
+        self.server_packs.prompt = None;
+        self.server_packs.packs.disconnect();
+        self.tick_server_packs();
+    }
+
+    /// `handleResourcePackPush`.
+    pub(super) fn handle_pack_push(&mut self, p: ResourcePackPush) {
+        if !valid_url(&p.url) {
+            self.send_pack_status(p.id, action::INVALID_URL);
+            return;
+        }
+        let setting = self.server_setting();
+        let prompt = Prompt::for_server(setting);
+        if prompt != Prompt::Pending && (!p.required || prompt != Prompt::Declined) {
+            self.server_packs
+                .packs
+                .push(p.id, &p.url, parse_sha1(&p.hash));
+            return;
+        }
+        // addOrUpdatePackPrompt: one prompt for every pack pushed before it is answered.
+        let text = p.prompt.as_ref().map(|t| comp_text(&tag_to_json(t)));
+        let state = &mut self.server_packs;
+        let open = state.prompt.get_or_insert(PackPrompt {
+            requests: Vec::new(),
+            required: p.required,
+            prompt: None,
+        });
+        open.requests.push((p.id, p.url, p.hash));
+        open.required = p.required;
+        open.prompt = text;
+        self.capture(false);
+    }
+    /// `handleResourcePackPop`: one pack, or all of them.
+    pub(super) fn handle_pack_pop(&mut self, id: Option<u128>) {
+        match id {
+            Some(id) => self.server_packs.packs.pop(id),
+            None => self.server_packs.packs.pop_all(),
+        }
+    }
+    /// The joined server's entry in the server list: its `acceptTextures`.
+    fn server_setting(&self) -> Option<bool> {
+        let address = self.server_packs.address.as_deref()?;
+        servers::load(&multiplayer::servers_file(&saves()))
+            .into_iter()
+            .find(|s| s.ip == address)?
+            .accept_textures
+    }
+    fn send_pack_status(&self, id: u128, status: i32) {
+        if let Some(r) = &self.remote {
+            r.session.send_pack_status(id, status);
+        }
+    }
+
+    /// The prompt's answer (`PackConfirmScreen`'s callback): the server's
+    /// setting follows it, declining a required pack disconnects, and every
+    /// pack it asked about is pushed.
+    pub(super) fn answer_pack_prompt(&mut self, yes: bool) -> Result<()> {
+        let Some(prompt) = self.server_packs.prompt.take() else {
+            return Ok(());
+        };
+        if self.player.is_some() && self.screen == super::Screen::Playing {
+            self.capture(true);
+        }
+        let setting = if yes {
+            self.server_packs.packs.allow();
+            Some(true)
+        } else {
+            self.server_packs.packs.reject();
+            if prompt.required {
+                let reason = Text::translate("multiplayer.requiredTexturePrompt.disconnect", &[]);
+                return self.leave_server(Some(reason.plain()));
+            }
+            Some(false)
+        };
+        for (id, url, hash) in prompt.requests {
+            self.server_packs.packs.push(id, &url, parse_sha1(&hash));
+        }
+        // ServerList.saveSingleServer.
+        if let Some(address) = &self.server_packs.address {
+            let file = multiplayer::servers_file(&saves());
+            let mut list = servers::load(&file);
+            for entry in list.iter_mut().filter(|s| &s.ip == address) {
+                entry.accept_textures = setting;
+            }
+            if let Err(e) = servers::save(&file, &list) {
+                log::warn!("Horizon: could not save {}: {e}", file.display());
+            }
+        }
+        Ok(())
+    }
+
+    /// Runs what the packs need (`createUpdateScheduler`): the downloads
+    /// that finished, the ones to start, a resource reload when the active
+    /// packs change, and the statuses for the server.
+    pub(super) fn tick_server_packs(&mut self) {
+        // A reload waits for the world's resources (`reload_packs`).
+        if self.rest_loader.is_some() || self.world_loader.is_some() {
+            return;
+        }
+        let finished = self
+            .server_packs
+            .queue
+            .as_ref()
+            .map(download::Queue::finished)
+            .unwrap_or_default();
+        for batch in finished {
+            self.server_packs.packs.downloaded(batch);
+        }
+        while self.server_packs.packs.wants_tick() {
+            let tick = self.server_packs.packs.tick();
+            if !tick.download.is_empty() {
+                self.start_pack_downloads(tick.download);
+            }
+            if let Some(mut load) = tick.reload {
+                while let Some(recovery) = {
+                    let ok = self.reload_server_packs(&load);
+                    self.server_packs.packs.reloaded(ok)
+                } {
+                    load = recovery;
+                }
+            }
+        }
+        for (id, status) in self.server_packs.packs.take_replies() {
+            self.send_pack_status(id, status);
+        }
+    }
+    fn start_pack_downloads(&mut self, requests: Vec<horizon_client::server_packs::Request>) {
+        let state = &mut self.server_packs;
+        if state.queue.is_none() {
+            let dir = std::env::current_dir()
+                .unwrap_or_default()
+                .join("downloads");
+            match download::Queue::open(dir) {
+                Ok(queue) => state.queue = Some(queue),
+                Err(e) => {
+                    log::error!("Horizon: failed to open the download queue: {e}");
+                    let failed = requests.iter().map(|r| r.id).collect();
+                    state.packs.downloaded(horizon_client::server_packs::Batch {
+                        downloaded: Vec::new(),
+                        failed,
+                    });
+                    return;
+                }
+            }
+        }
+        let headers = download::headers(&state.user.0, state.user.1);
+        if let Some(queue) = &state.queue {
+            queue.download(requests, headers);
+        }
+    }
+    /// `DownloadedPackSource.startReload`: the packs on top of the player's
+    /// own, then `Minecraft.reloadResourcePacks`. False when a pack has no
+    /// readable `pack.mcmeta` or the reload failed.
+    fn reload_server_packs(&mut self, load: &[(u128, PathBuf)]) -> bool {
+        let packs: Option<Vec<_>> = load
+            .iter()
+            .map(|(id, path)| packs::server_pack(*id, path))
+            .collect();
+        let Some(packs) = packs else {
+            log::warn!("Horizon: invalid pack metadata in a server pack, ignoring all");
+            return false;
+        };
+        self.server_packs.active = packs;
+        match self.reload_selected_packs() {
+            Ok(()) => true,
+            Err(e) => {
+                log::warn!("Horizon: server resource pack reload failed: {e}");
+                false
+            }
+        }
+    }
+
+    pub(super) fn draw_pack_prompt(&self, batch: &mut HudBatch) {
+        let Some(prompt) = &self.server_packs.prompt else {
+            return;
+        };
+        let atlas = &self.gui.atlas;
+        let (w, h) = (batch.width, batch.height);
+        if self.player.is_none() {
+            // In place of the connecting screen, on its background.
+            batch.fill(
+                atlas,
+                0.0,
+                0.0,
+                w,
+                h,
+                horizon_client::hud::rgba(20, 20, 20, 255),
+            );
+        }
+        ui::menu_background(batch, atlas, 0.0, 0.0, w, h, self.player.is_some());
+        let (_, _, [yes, no]) = prompt.texts();
+        prompt
+            .layout(atlas, (w, h))
+            .draw(batch, atlas, self.cursor, [&yes, &no]);
+    }
+    /// A left click on the prompt: its answer when it hit a button.
+    pub(super) fn pack_prompt_click(&mut self) -> Result<()> {
+        let Some(prompt) = &self.server_packs.prompt else {
+            return Ok(());
+        };
+        let answer = prompt
+            .layout(&self.gui.atlas, self.gui_size())
+            .answer_at(self.cursor);
+        match answer {
+            Some(yes) => {
+                self.audio.play_button_click();
+                self.answer_pack_prompt(yes)
+            }
+            None => Ok(()),
+        }
+    }
+}
@@ -1,128 +0,0 @@
-//! The selected Horizon shader pack (`shaderPack` in `horizon-graphics.txt`,
-//! docs/shader-packs.md): loaded from `shaderpacks/`, given to the renderer,
-//! and loaded again when the selection changes, on F3 + T, or when its files
-//! change (checked twice a second). A pack that fails leaves the last good
-//! one (or the vanilla picture) on and says why in chat.
-use super::Game;
-use horizon_client::shader_pack::{self, ShaderPack, Stamp};
-use horizon_client::text::Text;
-use horizon_shaderpack::properties::SkyDirectives;
-use std::{
-    path::PathBuf,
-    time::{Duration, Instant},
-};
-
-#[derive(Default)]
-pub(super) struct ShaderPacks {
-    /// The pack the renderer runs.
-    pack: Option<ShaderPack>,
-    /// The selection and its files at the last load, success or not.
-    selected: String,
-    stamp: Stamp,
-    checked: Option<Instant>,
-}
-
-impl ShaderPacks {
-    /// The loaded pack's folder name.
-    pub(super) fn id(&self) -> Option<&str> {
-        self.pack.as_ref().map(|p| p.id.as_str())
-    }
-    /// What a loaded Java pack changes in the vanilla sky of `dimension`
-    /// (0 overworld, -1 the Nether, 1 the End): its `sunPathRotation`, and
-    /// whether it keeps the clouds, sun and moon (Iris's sky mixins).
-    pub(super) fn java_sky(&self, dimension: i8) -> Option<(f32, SkyDirectives)> {
-        let java = self.pack.as_ref()?.java.as_ref()?;
-        let folder = &java.folders[java.folder_for(dimension)?];
-        Some((folder.directives.sun_path_rotation, java.sky))
-    }
-}
-
-pub(super) fn dir() -> PathBuf {
-    shader_pack::folder()
-}
-
-impl Game<'_> {
-    /// Load the selected pack and give it to the renderer.
-    pub(super) fn load_shader_pack(&mut self) {
-        let id = self.settings.horizon.shader_pack.clone();
-        let dir = dir();
-        let state = &mut self.shader_packs;
-        state.selected = id.clone();
-        state.checked = Some(Instant::now());
-        let pack = if id.is_empty() {
-            state.stamp = Stamp::default();
-            None
-        } else {
-            state.stamp = Stamp::of(&dir.join(&id));
-            // Java packs are told which GPU they run on.
-            let (vendor, renderer) = self.renderer.as_ref().map_or(("Unknown", ""), |r| {
-                let name = r.info.name.as_str();
-                (
-                    horizon_client::java_pack::vendor_name(r.info.vendor, name),
-                    name,
-                )
-            });
-            let values = shader_pack::load_values(&dir, &id);
-            match ShaderPack::load_any(&dir.join(&id), &values, vendor, renderer) {
-                Ok(pack) => Some(pack),
-                Err(e) => return self.shader_pack_error(&id, &e),
-            }
-        };
-        if let Some(r) = self.renderer.as_mut()
-            && let Err(e) = r.set_shader_pack(pack.as_ref())
-        {
-            return self.shader_pack_error(&id, &e.to_string());
-        }
-        self.shader_packs.pack = pack;
-        self.ui.options.shader_pack_error = None;
-    }
-    /// Give the loaded pack to the renderer (also after it is rebuilt).
-    pub(super) fn apply_shader_pack(&mut self) -> horizon_client::Result<()> {
-        match self.renderer.as_mut() {
-            Some(r) => r.set_shader_pack(self.shader_packs.pack.as_ref()),
-            None => Ok(()),
-        }
-    }
-    /// Every frame: a new selection or edited pack files load it again.
-    pub(super) fn poll_shader_pack(&mut self) {
-        let state = &mut self.shader_packs;
-        if self.settings.horizon.shader_pack != state.selected {
-            return self.load_shader_pack();
-        }
-        if state.selected.is_empty()
-            || state
-                .checked
-                .is_some_and(|t| t.elapsed() < Duration::from_millis(500))
-        {
-            return;
-        }
-        state.checked = Some(Instant::now());
-        if Stamp::of(&dir().join(&state.selected)) != state.stamp {
-            self.load_shader_pack();
-        }
-    }
-    /// A file dropped on the window: a shader pack while the Shader Packs
-    /// page shows (`OptionsUi::drop_shader_pack`).
-    pub(super) fn drop_shader_pack(&mut self, path: &std::path::Path) {
-        match self.ui.options.drop_shader_pack(&mut self.settings, path) {
-            Some(Ok(())) => {
-                self.settings.save(&Self::options_path());
-                self.load_shader_pack();
-            }
-            Some(Err(e)) => {
-                log::warn!("Horizon: shader pack {}: {e}", path.display());
-                self.system_message(Text::literal(format!("Shader pack: {e}")));
-            }
-            None => {}
-        }
-    }
-    fn shader_pack_error(&mut self, id: &str, error: &str) {
-        log::warn!("Horizon: shader pack {id}: {error}");
-        // The Shader Packs page says why on the pack's row: the first line,
-        // since translator errors go on with a drawn source excerpt.
-        let first = error.lines().map(str::trim).find(|l| !l.is_empty());
-        self.ui.options.shader_pack_error =
-            Some((id.to_owned(), first.unwrap_or(error).to_owned()));
-        self.system_message(Text::literal(format!("Shader pack {id}: {error}")));
-    }
-}
@@ -1,12 +1,13 @@
 //! The sign editing screen (`SignEditScreen` / `HangingSignEditScreen`):
 //! opened when a sign is placed, four lines limited to the sign's line
 //! width, Up/Down/Enter move between lines, Escape or Done closes.
-use super::Game;
+use super::{Game, lan::LanHost};
 use horizon_client::{
    containers::BlockEntity,
    hud::{HudBatch, rgba},
    signs::wood_type,
 };
+use horizon_protocol::packets::play::{self, Clientbound as C, Serverbound as S};
 use std::time::Instant;
 use winit::{
    event::{ElementState, KeyEvent},
@@ -33,14 +34,95 @@ impl Game<'_> {
        self.right = false;
        self.capture(false);
    }
+    /// `AbstractSignEditScreen.removed`: a server's client sends what it
+    /// wrote (ServerboundSignUpdatePacket); the window's own world keeps it
+    /// and sends it to its guests (`sendBlockUpdated`).
    pub(super) fn close_sign_editor(&mut self) {
        if let Some(edit) = self.sign_edit.take() {
-            self.world
-                .modified
-                .insert((edit.pos.0 >> 4, edit.pos.2 >> 4));
+            if self.remote.is_some() {
+                if let Some(BlockEntity::Sign(sign)) = self.world.block_entities.get(&edit.pos) {
+                    let side = if edit.front { &sign.front } else { &sign.back };
+                    self.send(S::SignUpdate(play::SignUpdate {
+                        pos: [edit.pos.0, edit.pos.1, edit.pos.2],
+                        lines: side.lines.clone(),
+                        front: edit.front,
+                    }));
+                }
+            } else {
+                self.mark_block_entity_updated(edit.pos);
+            }
        }
        self.capture(true);
    }
+    /// `ServerPlayer.openTextEdit` for the guest whose action opened a sign:
+    /// the block, then the editor, on its client, and the guest may write on it.
+    pub(super) fn lan_open_sign_editor(&mut self, host: &mut LanHost, conn: u32, edit: SignEditor) {
+        let pos = [edit.pos.0, edit.pos.1, edit.pos.2];
+        let state = self.world.block(pos[0], pos[1], pos[2]).0 as i32;
+        host.hub
+            .send_to(conn, &C::BlockUpdate(play::BlockUpdate { pos, state }));
+        host.hub.send_to(
+            conn,
+            &C::OpenSignEditor(play::OpenSignEditor {
+                pos,
+                front: edit.front,
+            }),
+        );
+        host.play.entry(conn).or_default().sign_editing = Some(pos);
+    }
+    /// `ServerGamePacketListenerImpl.handleSignUpdate`: the lines, formatting
+    /// codes stripped, go on the sign the guest may write on unless it is
+    /// waxed (`SignBlockEntity.updateSignText`); a guest gone out of reach
+    /// may no longer write (`playerIsTooFarAwayToEdit`).
+    pub(super) fn lan_sign_update(&mut self, host: &mut LanHost, conn: u32, p: play::SignUpdate) {
+        let Some(g) = host.hub.guest(conn) else {
+            return;
+        };
+        let near = super::lan_stations::within_reach(g, p.pos);
+        let Some(play) = host.play.get_mut(&conn) else {
+            return;
+        };
+        if !near {
+            play.sign_editing = None;
+        }
+        if play.sign_editing != Some(p.pos) {
+            log::warn!("{} just tried to change non-editable sign", g.name);
+            return;
+        }
+        let key = (p.pos[0], p.pos[1], p.pos[2]);
+        let Some(BlockEntity::Sign(sign)) = self.world.block_entities.get_mut(&key) else {
+            return;
+        };
+        if sign.waxed {
+            return;
+        }
+        let side = if p.front {
+            &mut sign.front
+        } else {
+            &mut sign.back
+        };
+        for (line, new) in side.lines.iter_mut().zip(&p.lines) {
+            *line = horizon_client::clipboard::strip_formatting(new);
+        }
+        play.sign_editing = None;
+        self.mark_block_entity_updated(key);
+    }
+    /// `ClientPacketListener.handleOpenSignEditor`: the editor on a sign this
+    /// client has.
+    pub(super) fn remote_open_sign_editor(&mut self, p: play::OpenSignEditor) {
+        let key = (p.pos[0], p.pos[1], p.pos[2]);
+        if matches!(
+            self.world.block_entities.get(&key),
+            Some(BlockEntity::Sign(_))
+        ) {
+            self.open_sign_editor(key, p.front);
+        } else {
+            log::warn!(
+                "ignoring openTextEdit on a block that is no sign at {:?}",
+                p.pos
+            );
+        }
+    }
    pub(super) fn sign_edit_key(&mut self, event: &KeyEvent) {
        if event.state != ElementState::Pressed {
            return;
@@ -219,12 +219,11 @@ pub(super) fn spawn_loader(
        .name("resource-loader".into())
        .spawn(move || {
            let mut pack_error = None;
-            let root = packs::startup_root(&vanilla_root, &settings.resource_packs).unwrap_or_else(
-                |error| {
+            let root = packs::startup_root(&vanilla_root, &settings.resource_packs, &[])
+                .unwrap_or_else(|error| {
                    pack_error = Some(error.to_string());
                    vanilla_root.clone()
-                },
-            );
+                });
            let root = mods::content_root(&root, &settings.mods.enabled, &dev_mods);
            let result = load_resources(
                root,
@@ -367,11 +366,6 @@ impl Loading {
                    let _ = std::fs::create_dir_all(&dir);
                    packs::open_folder(&dir);
                }
-                Event::OpenShaderPackFolder => {
-                    let dir = horizon_client::shader_pack::folder();
-                    let _ = std::fs::create_dir_all(&dir);
-                    packs::open_folder(&dir);
-                }
                Event::Credits => {
                    if let Some(gui) = &self.gui {
                        let name = self.options.as_ref().map_or_else(
@@ -387,9 +381,6 @@ impl Loading {
                        self.menu.win = Some((screen, Instant::now()));
                    }
                }
-                Event::ReloadShaderPack => {
-                    self.save_menu_settings();
-                }
                // The startup menu runs before the game opens a control socket.
                Event::ButtonClick | Event::CopyAgentDetails => {}
            }
@@ -455,17 +446,6 @@ impl Loading {
                }
                self.apply_menu_settings();
            }
-            WindowEvent::DroppedFile(path) => {
-                match self
-                    .menu
-                    .options
-                    .drop_shader_pack(&mut self.settings, &path)
-                {
-                    Some(Ok(())) => self.save_menu_settings(),
-                    Some(Err(e)) => log::warn!("Horizon: shader pack {}: {e}", path.display()),
-                    None => {}
-                }
-            }
            WindowEvent::RedrawRequested => self.draw(),
            WindowEvent::ModifiersChanged(modifiers) => self.menu.modifiers = modifiers.state(),
            WindowEvent::Focused(false) => {
@@ -10,7 +10,7 @@ pub(super) const HELP: &[&str] = &[
    "use X Y Z                      open the block's menu as if right-clicked",
    "click-slot ID [right] [shift]  click a menu slot (0-35 inventory, 300+ container, 600+ station, 650 result)",
    "click-gui X Y [right] [shift]  click at GUI pixel X Y relative to the menu's top-left corner",
-    "book [next|back|take|done]     the open book or lectern: its page, or press one of its buttons",
+    "book [next|back|take|sign|done] the open book or lectern: its page, or press one of its buttons",
    "type TEXT | type-back          type into the anvil name box / delete one character",
    "enchant ID LEVEL               enchant the held item (books store the enchantment)",
    "potion ITEM POTION             give a potion item (potion, splash_potion, lingering_potion, tipped_arrow)",
@@ -5,34 +5,13 @@ use super::Game;
 use horizon_client::{
    gossip::{self, GossipType},
    items::ItemStack,
-    mobs::{Mob, Species, spawning, villager},
+    mobs::{Mob, Species, spawning, villager, villager_brain},
 };
-use horizon_core::{geometry::Vec3, random::RandomSource};
+use horizon_core::geometry::Vec3;

 fn block_of(p: Vec3) -> [i32; 3] {
    [p.x.floor() as i32, p.y.floor() as i32, p.z.floor() as i32]
 }
-/// `SpawnUtil.Strategy.LEGACY_IRON_GOLEM`: what a golem will not land on.
-fn golem_floor_ok(name: &str) -> bool {
-    !matches!(
-        name,
-        "minecraft:cobweb"
-            | "minecraft:cactus"
-            | "minecraft:glass_pane"
-            | "minecraft:conduit"
-            | "minecraft:ice"
-            | "minecraft:tnt"
-            | "minecraft:glowstone"
-            | "minecraft:beacon"
-            | "minecraft:sea_lantern"
-            | "minecraft:frosted_ice"
-            | "minecraft:tinted_glass"
-            | "minecraft:glass"
-    ) && !name.ends_with("_stained_glass_pane")
-        && !name.ends_with("_stained_glass")
-        && !name.ends_with("leaves")
-}
-
 impl Game<'_> {
    fn villager_index(&self, id: u32) -> Option<usize> {
        self.mobs
@@ -76,88 +55,46 @@ impl Game<'_> {
            return;
        };
        let now = self.world.game_time;
-        if !villager::ext(&self.mobs[i]).is_some_and(|e| e.wants_golem(now)) {
+        let Some(near) = villager::golem_summoners(&self.mobs, i, now, needed) else {
            return;
-        }
-        let at = self.mobs[i].position;
-        let nearby: Vec<usize> = self
-            .mobs
-            .iter()
-            .enumerate()
-            .filter(|(_, m)| {
-                m.species() == Species::Villager
-                    && m.alive()
-                    && (m.position.x - at.x).abs() <= 10.0
-                    && (m.position.y - at.y).abs() <= 10.0
-                    && (m.position.z - at.z).abs() <= 10.0
-            })
-            .map(|(j, _)| j)
-            .collect();
-        let wanting = nearby
-            .iter()
-            .filter(|j| villager::ext(&self.mobs[**j]).is_some_and(|e| e.wants_golem(now)))
-            .take(5)
-            .count();
-        if wanting < needed {
-            return;
-        }
-        if self.try_spawn_iron_golem(block_of(at)) {
-            for j in nearby {
-                villager::ext_mut(&mut self.mobs[j]).golem_until = now + 599;
+        };
+        if self.try_spawn_iron_golem(block_of(self.mobs[i].position)) {
+            for j in near {
+                villager_brain::golem_detected(&mut self.mobs[j], now);
            }
        }
    }
-    /// `SpawnUtil.trySpawnMob(IRON_GOLEM, ..., 10 attempts, 8 across, 6 up
-    /// and down, LEGACY_IRON_GOLEM)`.
+    /// `SpawnUtil.trySpawnMob(IRON_GOLEM, ...)`: a golem near `start`, with
+    /// the ambient sound `trySpawnMob` plays.
    fn try_spawn_iron_golem(&mut self, start: [i32; 3]) -> bool {
-        for _ in 0..10 {
-            let r = &mut self.world.random;
-            let dx = r.next_int_bound(17).unwrap_or(8) - 8;
-            let dz = r.next_int_bound(17).unwrap_or(8) - 8;
-            let (x, z) = (start[0] + dx, start[2] + dz);
-            let mut y = start[1] + 6;
-            let mut above = self.world.block(x, y, z);
-            let mut found = None;
-            for _ in 0..=12 {
-                y -= 1;
-                let here = self.world.block(x, y, z);
-                let f = self.res.facts().get(here);
-                let above_f = self.res.facts().get(above);
-                let air_or_liquid = self.res.facts().is_air(above)
-                    || above_f.fluid != horizon_client::blocks::Fluid::None;
-                let solid =
-                    self.res.mob_data().state(here).flags & horizon_client::mobs::data::SOLID != 0
-                        || f.name.as_ref() == "minecraft:powder_snow";
-                if golem_floor_ok(&f.name) && air_or_liquid && solid {
-                    found = Some(y + 1);
-                    break;
-                }
-                above = here;
-            }
-            let Some(y) = found else { continue };
-            // IronGolem.checkSpawnRules: a floor and three free blocks.
-            let free = |g: &Self, yy: i32| {
-                g.res.mob_data().state(g.world.block(x, yy, z)).flags
-                    & horizon_client::mobs::data::VALID_EMPTY_SPAWN
-                    != 0
-            };
-            if !(0..4).all(|k| free(self, y + k)) {
-                continue;
-            }
-            let at = [f64::from(x) + 0.5, f64::from(y), f64::from(z) + 0.5];
-            if let Some(id) = self.spawn_mob_for("minecraft:iron_golem", at, false, true)
-                && let Some(m) = self.mobs.iter_mut().find(|m| m.id == id)
-            {
-                let sound = m.kind.sounds[0];
-                if !sound.is_empty() {
-                    let at = m.center();
-                    self.audio
-                        .play(&format!("minecraft:{sound}"), Some(at), 1.0, 1.0);
-                }
-                return true;
-            }
+        let Some(kind) = self.res.mob_types().get("minecraft:iron_golem").cloned() else {
+            return false;
+        };
+        let id = self.next_entity + 1;
+        let mut random = self.world.random.clone();
+        let golem = villager::summon_golem(
+            &self.mob_world_base(&[]),
+            start,
+            &mut random,
+            |random, at, yaw| {
+                let mut m = Mob::new(id, kind.clone(), at, yaw);
+                villager::finalize_summoned_golem(&mut m, random);
+                m
+            },
+        );
+        self.world.random = random;
+        let Some(golem) = golem else {
+            return false;
+        };
+        self.next_entity = id;
+        let sound = golem.kind.sounds[0];
+        if !sound.is_empty() {
+            let at = golem.center();
+            self.audio
+                .play(&format!("minecraft:{sound}"), Some(at), 1.0, 1.0);
        }
-        false
+        self.mobs.push(golem);
+        true
    }

    /// `VillagerMakeLove.tryToGiveBirth`: both eat, a free bed within 48
@@ -22,6 +22,14 @@ const PLAYER_KNOCKBACK: f32 = 1.22;
 /// `BreezeWindCharge.RADIUS`.
 const BREEZE_RADIUS: f32 = 3.0;

+/// A burst `wind_burst` puts off until a guest's turn is over.
+pub(super) struct Burst {
+    center: [f64; 3],
+    radius: f32,
+    multiplier: f32,
+    breeze: bool,
+    wind_charge: bool,
+}
 /// `Projectile.deflect` with `ProjectileDeflection.REVERSE`.
 pub(super) fn reverse(p: &mut Projectile, jitter: f32) {
    p.velocity = Vec3::new(
@@ -196,7 +204,9 @@ impl Game<'_> {
        set.into_iter().collect()
    }
    /// `ServerExplosion.hurtEntities` for a calculator that damages nothing:
-    /// knockback scaled by distance, exposure and the multiplier.
+    /// knockback scaled by distance, exposure and the multiplier. Returns the
+    /// guests it pushed and by how much (`hitPlayers`), which their clients
+    /// apply from the burst's packet.
    fn wind_knockback(
        &mut self,
        center: [f64; 3],
@@ -204,7 +214,7 @@ impl Game<'_> {
        multiplier: f32,
        wind_charge: bool,
        blocklike: bool,
-    ) {
+    ) -> Vec<(u32, [f64; 3])> {
        let diameter = f64::from(radius * 2.0);
        let distance = |p: [f64; 3]| {
            ((p[0] - center[0]).powi(2) + (p[1] - center[1]).powi(2) + (p[2] - center[2]).powi(2))
@@ -223,42 +233,30 @@ impl Game<'_> {
                [d[0] / l, d[1] / l, d[2] / l]
            }
        };
-        let multiplier = f64::from(multiplier);
-        // The player (not a spectator; a flying creative player takes none).
-        if let Some(p) = self.player.as_ref()
-            && !self.spectator()
-        {
-            let feet = [p.position.x, p.position.y, p.position.z];
-            let dist = distance(feet) / diameter;
-            let flying = self.creative && p.flying;
-            if dist <= 1.0 && !flying {
-                let w = f64::from(p.dimensions.width) / 2.0;
-                let h = f64::from(p.dimensions.height);
-                let eye = [
-                    feet[0],
-                    feet[1] + f64::from(p.dimensions.eye_height),
-                    feet[2],
-                ];
-                let exposure = self.seen_percent(
-                    center,
-                    [feet[0] - w, feet[1], feet[2] - w],
-                    [feet[0] + w, feet[1] + h, feet[2] + w],
-                );
-                let power = (1.0 - dist) * f64::from(exposure) * multiplier;
-                let dir = direction(eye);
-                if let Some(p) = self.player.as_mut() {
-                    p.velocity = Vec3::new(
-                        p.velocity.x + dir[0] * power,
-                        p.velocity.y + dir[1] * power,
-                        p.velocity.z + dir[2] * power,
-                    );
-                    // ServerPlayer.onExplosionHit: a wind charge's burst cancels the
-                    // fall; any other burst ends the grace of the last impulse.
-                    let at = p.position;
-                    p.impulse.set_ignore_fall_damage(wind_charge, Some(at));
+        // The player, then every other player in the level (LAN guests),
+        // each swapped in as the player. In a guest's turn (a mace's wind
+        // burst) the player is that guest.
+        let own = self.wind_push_player(center, radius, multiplier, wind_charge);
+        let mut pushed: Vec<_> = self.lan_acting.zip(own).into_iter().collect();
+        if let Some(mut host) = self.lan.take() {
+            let guests: Vec<u32> = host
+                .hub
+                .guests
+                .iter()
+                .filter(|g| host.hub.here(g) && g.loaded && !g.dead)
+                .map(|g| g.conn)
+                .collect();
+            for conn in guests {
+                let push = self.as_guest(&mut host, conn, |g| {
+                    g.wind_push_player(center, radius, multiplier, wind_charge)
+                });
+                if let Some(Some(push)) = push {
+                    pushed.push((conn, push));
                }
            }
+            self.lan = Some(host);
        }
+        let multiplier = f64::from(multiplier);
        let mut mobs = std::mem::take(&mut self.mobs);
        for m in mobs.iter_mut().filter(|m| m.alive()) {
            let feet = [m.position.x, m.position.y, m.position.z];
@@ -351,6 +349,67 @@ impl Game<'_> {
            push(t.position, &mut t.velocity, self);
        }
        self.tnts = tnts;
+        pushed
+    }
+    /// `ServerExplosion.hurtEntities` for the player (not a spectator, nor a
+    /// creative player flying): the push, less with explosion knockback
+    /// resistance, and `ServerPlayer.onExplosionHit`. Returns the push.
+    fn wind_push_player(
+        &mut self,
+        center: [f64; 3],
+        radius: f32,
+        multiplier: f32,
+        wind_charge: bool,
+    ) -> Option<[f64; 3]> {
+        if self.spectator() {
+            return None;
+        }
+        let resistance = self
+            .player
+            .as_mut()
+            .and_then(|p| p.attribute("minecraft:explosion_knockback_resistance").ok())
+            .unwrap_or(0.0);
+        let creative = self.creative;
+        let p = self.player.as_ref()?;
+        let feet = [p.position.x, p.position.y, p.position.z];
+        let dist = ((feet[0] - center[0]).powi(2)
+            + (feet[1] - center[1]).powi(2)
+            + (feet[2] - center[2]).powi(2))
+        .sqrt()
+            / f64::from(radius * 2.0);
+        if dist > 1.0 || creative && p.flying {
+            return None;
+        }
+        let w = f64::from(p.dimensions.width) / 2.0;
+        let h = f64::from(p.dimensions.height);
+        let eye = [
+            feet[0] - center[0],
+            feet[1] + f64::from(p.dimensions.eye_height) - center[1],
+            feet[2] - center[2],
+        ];
+        let exposure = self.seen_percent(
+            center,
+            [feet[0] - w, feet[1], feet[2] - w],
+            [feet[0] + w, feet[1] + h, feet[2] + w],
+        );
+        let power = (1.0 - dist) * f64::from(exposure) * f64::from(multiplier) * (1.0 - resistance);
+        let l = (eye[0] * eye[0] + eye[1] * eye[1] + eye[2] * eye[2]).sqrt();
+        let push = if l < 1.0e-5 {
+            [0.0; 3]
+        } else {
+            eye.map(|d| d / l * power)
+        };
+        let p = self.player.as_mut()?;
+        p.velocity = Vec3::new(
+            p.velocity.x + push[0],
+            p.velocity.y + push[1],
+            p.velocity.z + push[2],
+        );
+        // ServerPlayer.onExplosionHit: a wind charge's burst cancels the
+        // fall; any other burst ends the grace of the last impulse.
+        let at = p.position;
+        p.impulse.set_ignore_fall_damage(wind_charge, Some(at));
+        Some(push)
    }
    /// The burst: knockback, the blocks that react, the gust and the sound.
    pub(super) fn wind_burst(
@@ -361,13 +420,27 @@ impl Game<'_> {
        breeze: bool,
        wind_charge: bool,
    ) -> Result<()> {
+        // In a guest's turn (their charge landing, their mace's burst) the
+        // host holds the other players (`as_guest`): the burst waits for the
+        // turn to end so that it reaches every player, the guest too.
+        if self.lan_acting.is_some() && self.lan.is_none() {
+            self.creatures.wind_bursts.push(Burst {
+                center,
+                radius,
+                multiplier,
+                breeze,
+                wind_charge,
+            });
+            return Ok(());
+        }
        // ServerExplosion.explode: the blast is heard first.
        let ctx = horizon_client::sculk::Context::default();
        self.post_game_event("minecraft:explode", center, ctx);
        let mut targets = self.wind_positions(center, radius);
        // ServerExplosion.shouldAffectBlocklikeEntities
        let blocklike = !breeze && !wind_charge && self.ui.rules.bool("mob_griefing");
-        self.wind_knockback(center, radius, multiplier, wind_charge, blocklike);
+        let pushed = self.wind_knockback(center, radius, multiplier, wind_charge, blocklike);
+        let block_count = targets.len();
        // Explosion.canTriggerBlocks: a breeze's charge needs mob griefing.
        if !breeze || self.ui.rules.bool("mob_griefing") {
            // Util.shuffle(list, level.random)
@@ -396,6 +469,14 @@ impl Game<'_> {
        };
        self.particles
            .add(&ParticleOptions::simple(ty), center, [1.0, 0.0, 0.0]);
+        self.lan_wind_burst(center, radius, sound, block_count, &pushed);
+        Ok(())
+    }
+    /// The bursts guests' turns put off.
+    pub(super) fn flush_wind_bursts(&mut self) -> Result<()> {
+        for b in std::mem::take(&mut self.creatures.wind_bursts) {
+            self.wind_burst(b.center, b.radius, b.multiplier, b.breeze, b.wind_charge)?;
+        }
        Ok(())
    }
    /// `BlockBehaviour.onExplosionHit` for `TRIGGER_BLOCK`: doors, gates,
@@ -245,7 +245,6 @@ pub(super) fn make_streaming(
    streaming.biome_blend = settings.biome_blend;
    streaming.smooth_lighting = settings.smooth_lighting;
    streaming.cutout_leaves = settings.cutout_leaves;
-    streaming.cull_leaves = settings.horizon.cull_leaves;
    streaming.biome_zoom = BiomeZoom::new(obfuscate_seed(seed));
    streaming.sky_light = dim != Dim::Nether;
    streaming.nether_shading = dim == Dim::Nether;
@@ -35,7 +35,7 @@ fn entity_shader() -> String {
 mod entity_batch;
 mod weather;
 use entity_batch::EntityBatch;
-pub use entity_batch::WATER_MASK_OVERLAY;
+pub use entity_batch::{SHADOW_OVERLAY, WATER_MASK_OVERLAY};

 /// Window.getAppropriateLineWidth, in framebuffer pixels.
 pub fn outline_width(width: u32) -> f32 {
@@ -65,11 +65,9 @@ mod arena;
 mod cull;
 mod end_sky;
 mod flat;
-mod java_stages;
 pub mod lightning;
 mod lod;
 mod occlusion;
-mod pack_stages;
 mod page_runs;
 pub mod panorama;
 mod resident;
@@ -89,7 +87,6 @@ fn world_pass_after_culling<'e>(
    encoder: &'e mut wgpu::CommandEncoder,
    view: &wgpu::TextureView,
    depth: &wgpu::TextureView,
-    pack: bool,
 ) -> wgpu::RenderPass<'e> {
    encoder.begin_render_pass(&wgpu::RenderPassDescriptor {
        label: Some("Horizon world, after culling"),
@@ -106,11 +103,7 @@ fn world_pass_after_culling<'e>(
            view: depth,
            depth_ops: Some(wgpu::Operations {
                load: wgpu::LoadOp::Load,
-                store: if pack {
-                    wgpu::StoreOp::Store
-                } else {
-                    wgpu::StoreOp::Discard
-                },
+                store: wgpu::StoreOp::Discard,
            }),
            stencil_ops: None,
        }),
@@ -278,28 +271,6 @@ pub struct Frame<'a> {
    /// `Screen.extractBlurredBackground`: blur the frame by this radius
    /// (`menuBackgroundBlurriness`) before the screen is drawn over it.
    pub menu_blur: Option<f32>,
-    /// What a shader pack's `Frame` uniform reads beyond the rest of the frame.
-    pub shader: ShaderInputs,
-}
-/// A shader pack's view of the game this frame (docs/shader-packs.md, `Frame`).
-#[derive(Clone, Copy, Debug, Default)]
-pub struct ShaderInputs {
-    /// `Level.getRainLevel` and `getThunderLevel` at the partial tick.
-    pub rain: f32,
-    pub thunder: f32,
-    /// The camera's fog type: 0 air, 1 water, 2 lava, 3 powder snow.
-    pub submerged: u8,
-    /// 0 overworld, -1 the Nether, 1 the End.
-    pub dimension: i8,
-    pub has_sky_light: bool,
-    /// `DimensionType.moonPhase`, 0..=7.
-    pub moon_phase: u8,
-    /// The time of day as a fraction (0 sunrise, 0.25 noon) and the partial tick.
-    pub day_fraction: f32,
-    pub partial_tick: f32,
-    /// The block and sky light (0..15) of the block holding the camera
-    /// entity's eyes; no sky light without a sky.
-    pub eye_light: [u8; 2],
 }
 /// One frame of the world border wall (`WorldBorderRenderer.render`).
 #[derive(Clone, Debug)]
@@ -367,14 +338,10 @@ pub struct Renderer {
    /// (`crosshair_globals`).
    crosshair_group: wgpu::BindGroup,
    crosshair_globals: wgpu::Buffer,
-    shadow_pipeline: wgpu::RenderPipeline,
-    shadow_entity_pipeline: wgpu::RenderPipeline,
-    shadow_globals: wgpu::Buffer,
-    shadow_group: wgpu::BindGroup,
-    shadow_entity_group: wgpu::BindGroup,
    entity_pipeline: wgpu::RenderPipeline,
    weather: weather::Weather,
    crumbling_pipeline: wgpu::RenderPipeline,
+    shadow_blob_pipeline: wgpu::RenderPipeline,
    /// `RenderPipelines.WATER_MASK`: depth writes only, no colour.
    water_mask_pipeline: wgpu::RenderPipeline,
    cloud_pipeline: wgpu::RenderPipeline,
@@ -489,8 +456,6 @@ pub struct Renderer {
    occlusion: occlusion::Occlusion,
    /// Resolution scale and FXAA (Horizon settings).
    world_post: world_post::Post,
-    /// The selected shader pack's stages (Horizon setting; none by default).
-    pack: Option<Pack>,
    pub hud: HudRenderer,
    /// Vanilla's menu background blur, made on first use.
    menu_blur: Option<crate::menu_blur::MenuBlur>,
@@ -1312,38 +1277,6 @@ impl Renderer {
            usage: wgpu::BufferUsages::UNIFORM | wgpu::BufferUsages::COPY_DST,
            mapped_at_creation: false,
        });
-        let shadow_globals = device.create_buffer(&wgpu::BufferDescriptor {
-            label: Some("Shader pack shadow globals"),
-            size: std::mem::size_of::<Globals>() as u64,
-            usage: wgpu::BufferUsages::UNIFORM | wgpu::BufferUsages::COPY_DST,
-            mapped_at_creation: false,
-        });
-        let shadow_pipeline = device.create_render_pipeline(&wgpu::RenderPipelineDescriptor {
-            label: Some("Terrain shadow"),
-            layout: Some(&layout),
-            vertex: wgpu::VertexState {
-                module: &shader,
-                entry_point: Some("vs_terrain"),
-                compilation_options: Default::default(),
-                buffers: &terrain_buffers,
-            },
-            primitive: wgpu::PrimitiveState {
-                topology: tri,
-                cull_mode: Some(wgpu::Face::Back),
-                ..Default::default()
-            },
-            depth_stencil: Some(wgpu::DepthStencilState {
-                format: wgpu::TextureFormat::Depth32Float,
-                depth_write_enabled: Some(true),
-                depth_compare: Some(wgpu::CompareFunction::GreaterEqual),
-                stencil: Default::default(),
-                bias: Default::default(),
-            }),
-            multisample: Default::default(),
-            fragment: None,
-            multiview_mask: None,
-            cache: None,
-        });
        let prepared = prepared.unwrap_or_else(|| {
            PreparedTextures::new(sprite_pixels, sprite_size, layers, sprite_mips, forcefield)
        });
@@ -1457,16 +1390,6 @@ impl Renderer {
            &lightmap_view,
            &lightmap_sampler,
        );
-        let shadow_group = terrain_group(
-            &device,
-            "Shader pack shadow terrain resources",
-            &bindings,
-            &shadow_globals,
-            &sprite_views,
-            &sprite_sampler,
-            &lightmap_view,
-            &lightmap_sampler,
-        );
        let index_quads = 1 << 16;
        let indices = Self::quad_indices(&device, index_quads);
        let instance_capacity = 4096;
@@ -1628,32 +1551,6 @@ impl Renderer {
                },
            ],
        });
-        let shadow_entity_group = device.create_bind_group(&wgpu::BindGroupDescriptor {
-            label: Some("Shader pack shadow entity resources"),
-            layout: &entity_bindings,
-            entries: &[
-                wgpu::BindGroupEntry {
-                    binding: 0,
-                    resource: shadow_globals.as_entire_binding(),
-                },
-                wgpu::BindGroupEntry {
-                    binding: 1,
-                    resource: wgpu::BindingResource::TextureView(&atlas_view),
-                },
-                wgpu::BindGroupEntry {
-                    binding: 2,
-                    resource: wgpu::BindingResource::Sampler(&atlas_sampler),
-                },
-                wgpu::BindGroupEntry {
-                    binding: 3,
-                    resource: wgpu::BindingResource::TextureView(&lightmap_view),
-                },
-                wgpu::BindGroupEntry {
-                    binding: 4,
-                    resource: wgpu::BindingResource::Sampler(&lightmap_sampler),
-                },
-            ],
-        });
        let entity_layout = device.create_pipeline_layout(&wgpu::PipelineLayoutDescriptor {
            label: Some("Entity layout"),
            bind_group_layouts: &[Some(&entity_bindings)],
@@ -1764,32 +1661,6 @@ impl Renderer {
                wgpu::ColorWrites::ALL,
            )
        };
-        let shadow_entity_pipeline =
-            device.create_render_pipeline(&wgpu::RenderPipelineDescriptor {
-                label: Some("Entity shadow"),
-                layout: Some(&entity_layout),
-                vertex: wgpu::VertexState {
-                    module: &entity_shader,
-                    entry_point: Some("vs_entity"),
-                    compilation_options: Default::default(),
-                    buffers: &entity_vertex,
-                },
-                primitive: wgpu::PrimitiveState {
-                    cull_mode: None,
-                    ..Default::default()
-                },
-                depth_stencil: Some(wgpu::DepthStencilState {
-                    format: wgpu::TextureFormat::Depth32Float,
-                    depth_write_enabled: Some(true),
-                    depth_compare: Some(wgpu::CompareFunction::GreaterEqual),
-                    stencil: Default::default(),
-                    bias: Default::default(),
-                }),
-                multisample: Default::default(),
-                fragment: None,
-                multiview_mask: None,
-                cache: None,
-            });
        // RenderPipelines.WATER_MASK: the boat's water patch writes depth only.
        let water_mask_pipeline = entity_pipeline_with(
            "Water mask",
@@ -1815,6 +1686,26 @@ impl Renderer {
            CRUMBLING_BLEND,
            false,
        );
+        // RenderPipelines.ENTITY_SHADOW: translucent, depth test without
+        // writes. The quads lie on the block tops like vanilla's, but the
+        // terrain under them snaps to the subpixel grid at other vertices, so
+        // at a slant their depths differ by up to 1/256 of a pixel's depth
+        // slope and whole shadows failed the test. The bias covers that and
+        // the rounding, and stays below the 0.001 a model's feet sit higher
+        // (1/27 of a pixel's slope at the 16-block shadow range in 720p).
+        let shadow_blob_pipeline = entity_pipeline(
+            "Entity shadows",
+            None,
+            false,
+            wgpu::CompareFunction::GreaterEqual,
+            wgpu::DepthBiasState {
+                constant: 16,
+                slope_scale: 0.015,
+                clamp: 0.0,
+            },
+            alpha_blend,
+            false,
+        );
        let cloud_pipeline = entity_pipeline(
            "Clouds",
            Some(wgpu::Face::Back),
@@ -2324,14 +2215,10 @@ impl Renderer {
            debug_line_capacity: 4096,
            crosshair_group,
            crosshair_globals,
-            shadow_pipeline,
-            shadow_entity_pipeline,
-            shadow_globals,
-            shadow_group,
-            shadow_entity_group,
            entity_pipeline,
            weather,
            crumbling_pipeline,
+            shadow_blob_pipeline,
            water_mask_pipeline,
            cloud_pipeline,
            cloud_mesh: Default::default(),
@@ -2413,7 +2300,6 @@ impl Renderer {
            block_entity_revision: next_block_entity_revision(),
            occlusion: occlusion::Occlusion::new(crate::chunk::MIN_Y, crate::chunk::HEIGHT / 16),
            world_post,
-            pack: None,
            hud,
            menu_blur: None,
            info,
@@ -2723,10 +2609,11 @@ impl Renderer {
        first: u32,
        count: u32,
    ) {
+        let (draws, pages) = (&self.draws[..], &self.draw_pages[..]);
        let (mut i, end) = (first as usize, (first + count) as usize);
        while i < end {
-            let (page, index_page) = self.draw_pages[i];
-            let run = self.draw_pages[i..end]
+            let (page, index_page) = pages[i];
+            let run = pages[i..end]
                .iter()
                .take_while(|&&p| p == (page, index_page))
                .count();
@@ -2737,7 +2624,7 @@ impl Renderer {
                let offset = (i - base as usize) as u64 * 20;
                pass.multi_draw_indexed_indirect(indirect, offset, run as u32);
            } else {
-                for d in &self.draws[i..i + run] {
+                for d in &draws[i..i + run] {
                    pass.draw_indexed(d[2]..d[2] + d[0], d[3] as i32, d[4]..d[4] + 1);
                }
            }
@@ -2826,37 +2713,6 @@ impl Renderer {
            self.release_section(key);
        }
    }
-    /// Run `pack`'s stages over the world from now on (`None`: no pack, the
-    /// vanilla frame). On error the previous pack stays.
-    pub fn set_shader_pack(&mut self, pack: Option<&crate::shader_pack::ShaderPack>) -> Result<()> {
-        let format = self.config.format.remove_srgb_suffix();
-        self.pack = match pack {
-            Some(pack) => Some(match &pack.java {
-                Some(java) => Pack::Java(java_stages::JavaStages::new(
-                    &self.device,
-                    &self.queue,
-                    format,
-                    &pack.id,
-                    java,
-                )?),
-                None => Pack::Horizon(pack_stages::PackStages::new(
-                    &self.device,
-                    &self.queue,
-                    format,
-                    pack,
-                )?),
-            }),
-            None => None,
-        };
-        Ok(())
-    }
-    /// The folder name of the pack `set_shader_pack` gave.
-    pub fn shader_pack_id(&self) -> Option<&str> {
-        self.pack.as_ref().map(|p| match p {
-            Pack::Horizon(p) => p.id.as_str(),
-            Pack::Java(p) => p.id.as_str(),
-        })
-    }
    /// Horizon's resolution scale (world pixels per window pixel) and FXAA.
    pub fn set_world_post(&mut self, scale: f32, antialias: bool) {
        self.world_post.scale = scale.clamp(0.25, 2.0);
@@ -2886,16 +2742,6 @@ impl Renderer {
            &self.lightmap_view,
            &self.lightmap_sampler,
        );
-        self.shadow_group = terrain_group(
-            &self.device,
-            "Shader pack shadow terrain resources",
-            &self.terrain_layout,
-            &self.shadow_globals,
-            &views,
-            &self.sprite_sampler,
-            &self.lightmap_view,
-            &self.lightmap_sampler,
-        );
    }
    pub fn view_projection(&self, frame: &Frame) -> Mat4 {
        self.projection(
@@ -3159,15 +3005,6 @@ impl Renderer {
        };
        self.uploads
            .buffer(&mut encoder, &self.globals, 0, bytemuck::bytes_of(&globals));
-        let pack_uniform = shader_pack_uniform(
-            frame,
-            view,
-            world_projection(frame.fov_degrees, aspect, frame.depth_far) * frame.bob,
-            sun,
-            fog_color,
-            globals.fog,
-            globals.fog_ends,
-        );
        // GameRenderer.render3dHud: the hand's projection at hudFov, with the
        // bob in its pose rather than the projection (same product).
        let hand_projection = Mat4::from_cols_array(&crate::camera::hand_projection(
@@ -3238,8 +3075,9 @@ impl Renderer {
            visible_lods.sort_unstable_by_key(|v| (v.distance, v.key));
        }
        self.drawn_sections = visible.len() + visible_lods.len();
-        if self.drawn_sections as u64 > self.instance_capacity {
-            self.instance_capacity = (self.drawn_sections as u64).next_power_of_two();
+        let instances = self.drawn_sections;
+        if instances as u64 > self.instance_capacity {
+            self.instance_capacity = (instances as u64).next_power_of_two();
            self.instances = self.device.create_buffer(&wgpu::BufferDescriptor {
                label: Some("Section origins"),
                size: self.instance_capacity * 16,
@@ -3510,6 +3348,7 @@ impl Renderer {
            crumbling_quads,
            translucent_crumbling_quads,
            water_mask_quads,
+            shadow_quads,
        ] = self.entity_batch.update(
            frame.entities,
            frame.additive,
@@ -3517,8 +3356,11 @@ impl Renderer {
            frame.see_through,
        );
        let weather_quads = frame.weather.len() as u32 / 4;
-        let world_quads =
-            entity_quads + crumbling_quads + translucent_crumbling_quads + water_mask_quads;
+        let world_quads = entity_quads
+            + crumbling_quads
+            + translucent_crumbling_quads
+            + water_mask_quads
+            + shadow_quads;
        let cloud_quads = if let Some(input) = &frame.clouds {
            let (rebuilt, uniform) =
                crate::spans::time("clouds", || self.cloud_mesh.prepare(input));
@@ -3737,44 +3579,9 @@ impl Renderer {
            timer.begin(&mut encoder);
        }
        // The world's targets: the screen, or the scaled target of `post`.
-        let pack = self.pack.is_some() && !frame.title;
-        // What the pack reads beyond the world's colour and depth: each costs
-        // a pass (the shadow map, the G-buffer) or a copy (the opaque depth).
-        let (shadow_cfg, gbuffer, opaque_depth) = match self.pack.as_ref().filter(|_| pack) {
-            Some(Pack::Horizon(s)) => (
-                s.needs_shadow.then_some((s.shadow_res, s.shadow_dist)),
-                s.needs_gbuffer,
-                s.needs_opaque_depth,
-            ),
-            Some(Pack::Java(s)) => (None, false, s.reads_opaque_depth),
-            None => (None, false, false),
-        };
-        if let Some((shadow_res, shadow_dist)) = shadow_cfg {
-            self.world_post
-                .prepare_shadow(&self.device, shadow_res, shadow_dist, sun, -sun);
-            let shadow_globals = Globals {
-                view_proj: (self.world_post.shadow_proj * self.world_post.shadow_view)
-                    .to_cols_array_2d(),
-                ..globals
-            };
-            self.uploads.buffer(
-                &mut encoder,
-                &self.shadow_globals,
-                0,
-                bytemuck::bytes_of(&shadow_globals),
-            );
-        } else {
-            self.world_post.shadow_active = false;
-        }
-        let scaled = self.world_post.prepare(
-            &self.device,
-            [self.config.width, self.config.height],
-            pack,
-            world_post::Extras {
-                opaque_depth,
-                gbuffer,
-            },
-        );
+        let scaled = self
+            .world_post
+            .prepare(&self.device, [self.config.width, self.config.height]);
        let (world_view, world_depth) = match &scaled {
            Some((color, depth)) => (color, depth),
            None => (&view_target, &self.depth),
@@ -3783,36 +3590,6 @@ impl Renderer {
            cull.bind_depth(&self.device, world_depth);
        }
        let cull = self.cull.as_ref().filter(|_| culling && solid_draws > 0);
-        if shadow_cfg.is_some() {
-            let shadow_view = self.world_post.shadow_depth().clone();
-            let mut shadow_pass = encoder.begin_render_pass(&wgpu::RenderPassDescriptor {
-                label: Some("Horizon shadow"),
-                color_attachments: &[],
-                depth_stencil_attachment: Some(wgpu::RenderPassDepthStencilAttachment {
-                    view: &shadow_view,
-                    depth_ops: Some(wgpu::Operations {
-                        load: wgpu::LoadOp::Clear(0.0),
-                        store: wgpu::StoreOp::Store,
-                    }),
-                    stencil_ops: None,
-                }),
-                ..Default::default()
-            });
-            if solid_draws > 0 && !flat_frame {
-                shadow_pass.set_bind_group(0, &self.shadow_group, &[]);
-                shadow_pass.set_pipeline(&self.shadow_pipeline);
-                shadow_pass.set_index_buffer(self.indices.slice(..), wgpu::IndexFormat::Uint32);
-                shadow_pass.set_vertex_buffer(1, self.instances.slice(..));
-                self.draw_sections(&mut shadow_pass, &self.indirect, 0, 0, solid_draws);
-            }
-            if entity_quads > 0 {
-                shadow_pass.set_pipeline(&self.shadow_entity_pipeline);
-                shadow_pass.set_bind_group(0, &self.shadow_entity_group, &[]);
-                shadow_pass.set_index_buffer(self.indices.slice(..), wgpu::IndexFormat::Uint32);
-                shadow_pass.set_vertex_buffer(0, self.entity_buffer.slice(..));
-                shadow_pass.draw_indexed(0..entity_quads * 6, 0, 0..1);
-            }
-        }
        {
            let attachments = [Some(wgpu::RenderPassColorAttachment {
                view: world_view,
@@ -3841,9 +3618,8 @@ impl Renderer {
                    view: world_depth,
                    depth_ops: Some(wgpu::Operations {
                        load: wgpu::LoadOp::Clear(0.0),
-                        // A shader pack reads the world's depth, and
-                        // phase 2 of occlusion culling draws over it.
-                        store: if pack || cull.is_some() {
+                        // Phase 2 of occlusion culling draws over it.
+                        store: if cull.is_some() {
                            wgpu::StoreOp::Store
                        } else {
                            wgpu::StoreOp::Discard
@@ -3902,12 +3678,7 @@ impl Renderer {
                            drop(pass);
                            cull.test_pass(&mut encoder);
                            flat.flatten_phase2(&mut encoder);
-                            pass = world_pass_after_culling(
-                                &mut encoder,
-                                world_view,
-                                world_depth,
-                                pack,
-                            );
+                            pass = world_pass_after_culling(&mut encoder, world_view, world_depth);
                            pass.set_bind_group(0, &self.group, &[]);
                            pass.set_pipeline(&flat.solid);
                            flat.draw_phase2(&mut pass, vertices);
@@ -3931,12 +3702,7 @@ impl Renderer {
                            cull.test(&mut pass);
                            drop(pass);
                            cull.test_pass(&mut encoder);
-                            pass = world_pass_after_culling(
-                                &mut encoder,
-                                world_view,
-                                world_depth,
-                                pack,
-                            );
+                            pass = world_pass_after_culling(&mut encoder, world_view, world_depth);
                            pass.set_bind_group(0, &self.group, &[]);
                            pass.set_pipeline(&self.solid);
                            pass.set_index_buffer(
@@ -3972,6 +3738,17 @@ impl Renderer {
                pass.draw_indexed(0..crumbling_quads * 6, (entity_quads * 4) as i32, 0..1);
                pass.set_bind_group(0, &self.group, &[]);
            }
+            if shadow_quads > 0 {
+                pass.set_pipeline(&self.shadow_blob_pipeline);
+                pass.set_bind_group(0, &self.entity_group, &[]);
+                pass.set_vertex_buffer(0, self.entity_buffer.slice(..));
+                pass.draw_indexed(
+                    0..shadow_quads * 6,
+                    ((world_quads - shadow_quads) * 4) as i32,
+                    0..1,
+                );
+                pass.set_bind_group(0, &self.group, &[]);
+            }
            // BoatRenderer's water patch (RenderTypes.waterMask): depth only,
            // before translucent terrain, so no water shows inside the boat.
            if water_mask_quads > 0 {
@@ -4013,33 +3790,6 @@ impl Renderer {
                pass.set_vertex_buffer(0, self.debug_line_buffer.slice(..));
                pass.draw(0..4, debug_depth..debug_depth + debug_top);
            }
-            if opaque_depth {
-                drop(pass);
-                self.world_post.capture_opaque_depth(&mut encoder);
-                let attachments = [Some(wgpu::RenderPassColorAttachment {
-                    view: world_view,
-                    resolve_target: None,
-                    depth_slice: None,
-                    ops: wgpu::Operations {
-                        load: wgpu::LoadOp::Load,
-                        store: wgpu::StoreOp::Store,
-                    },
-                })];
-                pass = encoder.begin_render_pass(&wgpu::RenderPassDescriptor {
-                    label: Some("Horizon world, translucent"),
-                    color_attachments: &attachments,
-                    depth_stencil_attachment: Some(wgpu::RenderPassDepthStencilAttachment {
-                        view: world_depth,
-                        depth_ops: Some(wgpu::Operations {
-                            load: wgpu::LoadOp::Load,
-                            store: wgpu::StoreOp::Store,
-                        }),
-                        stencil_ops: None,
-                    }),
-                    ..Default::default()
-                });
-                pass.set_bind_group(0, &self.group, &[]);
-            }
            match self.flat.as_ref().filter(|_| flat_frame) {
                Some(flat) => {
                    pass.set_pipeline(&flat.translucent);
@@ -4111,49 +3861,7 @@ impl Renderer {
                );
            }
        }
-        if gbuffer && scaled.is_some() {
-            self.world_post.build_gbuffer(
-                &self.queue,
-                &mut encoder,
-                &pack_uniform,
-                frame.shader.eye_light,
-                frame.shader.rain,
-            );
-        }
-        if let (true, Some((color, depth)), Some(size), Some(stages)) =
-            (pack, &scaled, self.world_post.size(), self.pack.as_mut())
-        {
-            let output = match stages {
-                Pack::Horizon(stages) => stages.run(
-                    &self.device,
-                    &self.queue,
-                    &mut encoder,
-                    color,
-                    depth,
-                    size,
-                    &self.world_post,
-                    pack_uniform,
-                    frame.shader.eye_light,
-                ),
-                Pack::Java(stages) => stages.run(
-                    &self.device,
-                    &self.queue,
-                    &mut encoder,
-                    color,
-                    depth,
-                    size,
-                    &self.world_post,
-                    pack_uniform,
-                    java_stages::JavaFrame {
-                        eye_light: frame.shader.eye_light,
-                        sun_angle: frame.sky.sun_angle,
-                        moon_angle: frame.sky.moon_angle,
-                    },
-                ),
-            };
-            self.world_post
-                .finish_with(&mut encoder, &view_target, output);
-        } else if scaled.is_some() {
+        if scaled.is_some() {
            self.world_post.finish(&mut encoder, &view_target);
        }
        if hand_quads > 0 {
@@ -4481,66 +4189,6 @@ impl Frustum {
 /// Vanilla's `Projection`: reversed depth (near maps to 1, far to 0, tests
 /// are GREATER_THAN_OR_EQUAL), which keeps far faces a hair apart, like
 /// fire_side's 0.01 pixel in front of its block, from z-fighting.
-/// The prelude's `Frame` (`shader_pack_prelude.wgsl`); `resolution` and the
-/// time are filled per stage.
-fn shader_pack_uniform(
-    frame: &Frame,
-    view: Mat4,
-    projection: Mat4,
-    sun: Vec3,
-    fog_color: [f32; 4],
-    fog: [f32; 4],
-    fog_ends: [f32; 4],
-) -> pack_stages::FrameUniform {
-    let s = frame.shader;
-    let sky = frame.sky.sky_color;
-    pack_stages::FrameUniform {
-        view: view.to_cols_array_2d(),
-        projection: projection.to_cols_array_2d(),
-        inverse_view: view.inverse().to_cols_array_2d(),
-        inverse_projection: projection.inverse().to_cols_array_2d(),
-        camera_position: [
-            frame.camera.x as f32,
-            frame.camera.y as f32,
-            frame.camera.z as f32,
-            0.0,
-        ],
-        time: [0.0, 0.0, s.day_fraction, s.partial_tick],
-        sun: [sun.x, sun.y, sun.z, frame.sky.sun_angle.to_radians()],
-        moon: [-sun.x, -sun.y, -sun.z, f32::from(s.moon_phase)],
-        sky_color: [sky[0], sky[1], sky[2], 1.0],
-        fog_color,
-        fog: [fog[0], fog[1], fog_ends[0], fog_ends[1]],
-        weather: [s.rain, s.thunder, 0.0, 0.0],
-        camera_state: [
-            f32::from(s.submerged),
-            frame.night_vision,
-            frame.darkness.1,
-            0.0,
-        ],
-        view_params: [
-            0.05,
-            frame.depth_far,
-            frame.distance,
-            frame.fov_degrees.to_radians(),
-        ],
-        dimension: [
-            f32::from(s.dimension),
-            f32::from(u8::from(s.has_sky_light)),
-            0.0,
-            0.0,
-        ],
-        ..Default::default()
-    }
-}
-
-/// The selected shader pack on the GPU: a Horizon pack's WGSL stages, or a
-/// Java pack's translated programs.
-enum Pack {
-    Horizon(pack_stages::PackStages),
-    Java(java_stages::JavaStages),
-}
-
 /// The section the camera is in.
 fn camera_section(camera: DVec3) -> SectionKey {
    (
@@ -4625,14 +4273,14 @@ mod tests {
                normal: [0; 4],
            }; 4]
        };
-        let entities: Vec<_> = [(0, 0), (4, 1), (11, 2), (7, 3), (4, 4), (12, 7)]
+        let entities: Vec<_> = [(0, 0), (14, 9), (4, 1), (11, 2), (7, 3), (4, 4), (12, 7)]
            .into_iter()
            .flat_map(|(layer, id)| quad(layer, id))
            .collect();
        let mut batch = super::EntityBatch::default();
        let counts = batch.update(&entities, &quad(3, 5), &quad(0, 6), &quad(0, 8));
        let vertices = &batch.combined;
-        assert_eq!(counts, [4, 1, 1, 0]);
+        assert_eq!(counts, [4, 1, 1, 0, 1]);
        assert_eq!(
            vertices
                .as_chunks::<4>()
@@ -4640,7 +4288,7 @@ mod tests {
                .iter()
                .map(|q| q[0].light)
                .collect::<Vec<_>>(),
-            [0, 1, 3, 4, 2, 7, 5, 6, 8]
+            [0, 1, 3, 4, 2, 7, 9, 5, 6, 8]
        );
    }
    #[test]
@@ -4686,11 +4334,7 @@ mod tests {
        );
        assert!(files.len() >= 10, "{files:?}");
        for path in files {
-            let mut text = std::fs::read_to_string(&path).unwrap();
-            // Api 2's prelude follows api 1's (`shader_pack::ShaderPack::load`).
-            if path.ends_with("shader_pack_prelude_api2.wgsl") {
-                text = format!("{}\n{text}", crate::shader_pack::PRELUDE);
-            }
+            let text = std::fs::read_to_string(&path).unwrap();
            // entity.wgsl comes after the overlay's constants (entity_shader).
            let module = naga::front::wgsl::parse_str(&text)
                .or_else(|_| {
@@ -261,16 +261,18 @@ impl Cull {
            bind_group_layouts: &[Some(&layout), depth_layout.as_ref()],
            ..Default::default()
        });
-        // In the shader: no colour target, and phase 1's depth attached read
-        // only (a pass needs an attachment), its test left to the shader.
+        // In the shader (`InShader`): no colour target, and the depth
+        // attached read only (a pass needs an attachment), its test left to
+        // the shader.
+        let color_target = [Some(wgpu::ColorTargetState {
+            format: color,
+            blend: None,
+            write_mask: wgpu::ColorWrites::empty(),
+        })];
        let (fragment_entry, targets, depth_compare) = match depth_test {
            DepthTest::Early => (
                "fs_box_early",
-                &[Some(wgpu::ColorTargetState {
-                    format: color,
-                    blend: None,
-                    write_mask: wgpu::ColorWrites::empty(),
-                })][..],
+                &color_target[..],
                wgpu::CompareFunction::GreaterEqual,
            ),
            DepthTest::InShader => ("fs_box", &[][..], wgpu::CompareFunction::Always),
@@ -2,11 +2,14 @@
 use super::Vertex;

 /// Entity materials by a quad's overlay (`Vertex::layer`), in draw order:
-/// ordinary entities, breaking cracks (11), translucent breaking cracks (12)
-/// and the boat water mask (13, `RenderPipelines.WATER_MASK`).
-const MATERIALS: usize = 4;
+/// ordinary entities, breaking cracks (11), translucent breaking cracks (12),
+/// the boat water mask (13, `RenderPipelines.WATER_MASK`) and entity shadows
+/// (14, `RenderPipelines.ENTITY_SHADOW`).
+const MATERIALS: usize = 5;
 /// The overlay of depth-only quads that hide water (`RenderTypes.waterMask`).
 pub const WATER_MASK_OVERLAY: u32 = 13;
+/// The overlay of entity shadow quads (`RenderTypes.entityShadow`).
+pub const SHADOW_OVERLAY: u32 = 14;

 #[derive(Default)]
 pub(super) struct EntityBatch {
@@ -37,6 +40,7 @@ impl EntityBatch {
                11 => 1,
                12 => 2,
                WATER_MASK_OVERLAY => 3,
+                SHADOW_OVERLAY => 4,
                _ => 0,
            };
            self.buckets[material][counts[material]] = index;
@@ -88,12 +92,13 @@ mod tests {
    ) -> (Vec<Vertex>, [u32; MATERIALS]) {
        let mut combined = Vec::with_capacity(entities.len() + additive.len() + hand.len());
        let mut counts = [0; MATERIALS];
-        for (i, layer) in [0, 11, 12, 13].into_iter().enumerate() {
+        for (i, layer) in [0, 11, 12, 13, 14].into_iter().enumerate() {
            for quad in entities.as_chunks::<4>().0 {
                let material = match quad[0].layer {
                    11 => 11,
                    12 => 12,
                    13 => 13,
+                    14 => 14,
                    _ => 0,
                };
                if material == layer {
@@ -113,7 +118,7 @@ mod tests {
                pos: [index as f32, 2.0, 3.0],
                uv: [index as f32, 5.0],
                layer: if mixed {
-                    [7, 11, 12, 4, 13, 0][index / 4 % 6]
+                    [7, 11, 14, 12, 4, 13, 0][index / 4 % 7]
                } else {
                    0
                },
@@ -640,6 +640,7 @@ impl Flat {
        pass.set_bind_group(0, group, &[]);
        pass.dispatch_workgroups((*count).min(GROUP_LIMIT), count.div_ceil(GROUP_LIMIT), 1);
    }
+
    /// Draws `calls` with a flat pipeline set and `vertices` giving each
    /// page's vertex buffer.
    pub fn draw<'a>(
@@ -1,552 +0,0 @@
-//! A Horizon shader pack on the GPU (docs/shader-packs.md): each stage
-//! (`shadow`, `gbuffer`, `deferred`, `composite`, `final`) is a full-screen
-//! pass that reads the world's colour, depth, opaque depth, G-buffer normals
-//! and materials, shadow map, noise texture and the previous stage's output,
-//! and writes its own target; the last target goes to the screen through
-//! `world_post` (copy or FXAA) under the hand and HUD. Only exists while a
-//! pack is selected.
-use crate::shader_pack::{Rgba, ShaderPack, VERTEX_ENTRY};
-use horizon_shaderpack::uniforms::SmoothFloat;
-
-/// The `Frame` uniform of the prelude (`shader_pack_prelude.wgsl`).
-#[repr(C)]
-#[derive(Clone, Copy, Default, bytemuck::Pod, bytemuck::Zeroable)]
-pub struct FrameUniform {
-    pub view: [[f32; 4]; 4],
-    pub projection: [[f32; 4]; 4],
-    pub inverse_view: [[f32; 4]; 4],
-    pub inverse_projection: [[f32; 4]; 4],
-    pub camera_position: [f32; 4],
-    pub resolution: [f32; 4],
-    pub time: [f32; 4],
-    pub sun: [f32; 4],
-    pub moon: [f32; 4],
-    pub sky_color: [f32; 4],
-    pub fog_color: [f32; 4],
-    pub fog: [f32; 4],
-    pub weather: [f32; 4],
-    pub camera_state: [f32; 4],
-    pub view_params: [f32; 4],
-    pub dimension: [f32; 4],
-}
-
-/// The API 2 `FrameExt` uniform of the prelude (`shader_pack_prelude.wgsl`).
-#[repr(C)]
-#[derive(Clone, Copy, Default, bytemuck::Pod, bytemuck::Zeroable)]
-pub struct FrameExtUniform {
-    pub previous_view: [[f32; 4]; 4],
-    pub previous_projection: [[f32; 4]; 4],
-    pub shadow_view: [[f32; 4]; 4],
-    pub shadow_projection: [[f32; 4]; 4],
-    pub shadow_inverse_view: [[f32; 4]; 4],
-    pub shadow_inverse_projection: [[f32; 4]; 4],
-    pub previous_camera: [f32; 4],
-    pub shadow_params: [f32; 4],
-    pub environment: [f32; 4],
-}
-
-/// Iris's `noisetex` without a `texture.noise`: 256² random RGB, opaque.
-/// Horizon packs get the same one unless `[textures] noise` replaces it.
-pub(super) fn noise() -> Rgba {
-    const SIZE: u32 = 256;
-    let mut seed = 0x2545_f491_u32;
-    let pixels = (0..SIZE * SIZE * 4)
-        .map(|i| {
-            seed ^= seed << 13;
-            seed ^= seed >> 17;
-            seed ^= seed << 5;
-            if i % 4 == 3 { 255 } else { (seed >> 24) as u8 }
-        })
-        .collect();
-    Rgba {
-        width: SIZE,
-        height: SIZE,
-        pixels,
-    }
-}
-
-/// `image` as a sampled RGBA8 texture.
-pub(super) fn rgba_view(
-    device: &wgpu::Device,
-    queue: &wgpu::Queue,
-    label: &str,
-    image: &Rgba,
-) -> wgpu::TextureView {
-    let texture = device.create_texture(&wgpu::TextureDescriptor {
-        label: Some(label),
-        size: wgpu::Extent3d {
-            width: image.width,
-            height: image.height,
-            depth_or_array_layers: 1,
-        },
-        mip_level_count: 1,
-        sample_count: 1,
-        dimension: wgpu::TextureDimension::D2,
-        format: wgpu::TextureFormat::Rgba8Unorm,
-        usage: wgpu::TextureUsages::TEXTURE_BINDING | wgpu::TextureUsages::COPY_DST,
-        view_formats: &[],
-    });
-    queue.write_texture(
-        texture.as_image_copy(),
-        &image.pixels,
-        wgpu::TexelCopyBufferLayout {
-            offset: 0,
-            bytes_per_row: Some(image.width * 4),
-            rows_per_image: None,
-        },
-        texture.size(),
-    );
-    texture.create_view(&Default::default())
-}
-
-struct Pass {
-    pipeline: wgpu::RenderPipeline,
-    scale: f32,
-    target_format: wgpu::TextureFormat,
-    uniform: wgpu::Buffer,
-    uniform_ext: wgpu::Buffer,
-}
-/// A stage's output and the bindings that read the world into it.
-struct Target {
-    size: [u32; 2],
-    view: wgpu::TextureView,
-    group: wgpu::BindGroup,
-}
-
-pub struct PackStages {
-    pub id: String,
-    pub needs_shadow: bool,
-    /// The stages read the G-buffer (`build_gbuffer`) or the depth before
-    /// translucent geometry (`capture_opaque_depth`).
-    pub needs_gbuffer: bool,
-    pub needs_opaque_depth: bool,
-    pub shadow_res: u32,
-    pub shadow_dist: f32,
-    layout: wgpu::BindGroupLayout,
-    linear: wgpu::Sampler,
-    nearest: wgpu::Sampler,
-    repeat: wgpu::Sampler,
-    shadow_sampler: wgpu::Sampler,
-    noise_view: wgpu::TextureView,
-    passes: Vec<Pass>,
-    /// Built for this world target size and `world_post` generation.
-    targets: Vec<Target>,
-    /// `world_post`'s bindings of the last stage's output.
-    output: Option<wgpu::BindGroup>,
-    world_size: [u32; 2],
-    post_generation: u64,
-    started: std::time::Instant,
-    last: Option<std::time::Instant>,
-    frames: u32,
-    previous: Option<([[f32; 4]; 4], [[f32; 4]; 4], [f32; 3])>,
-    wetness: SmoothFloat,
-}
-
-fn stage_format(name: Option<&str>, default: wgpu::TextureFormat) -> wgpu::TextureFormat {
-    match name.map(str::to_lowercase).as_deref() {
-        Some("rgba16float" | "rgba16f") => wgpu::TextureFormat::Rgba16Float,
-        Some("rgba8unorm" | "rgba8" | "rgba") => wgpu::TextureFormat::Rgba8Unorm,
-        Some("rgb10a2unorm" | "rgb10_a2") => wgpu::TextureFormat::Rgb10a2Unorm,
-        _ => default,
-    }
-}
-
-impl PackStages {
-    /// The pipelines of a loaded (already validated) pack, or wgpu's error.
-    pub fn new(
-        device: &wgpu::Device,
-        queue: &wgpu::Queue,
-        format: wgpu::TextureFormat,
-        pack: &ShaderPack,
-    ) -> Result<Self, String> {
-        let texture = |binding, sample_type| wgpu::BindGroupLayoutEntry {
-            binding,
-            visibility: wgpu::ShaderStages::FRAGMENT,
-            ty: wgpu::BindingType::Texture {
-                sample_type,
-                view_dimension: wgpu::TextureViewDimension::D2,
-                multisampled: false,
-            },
-            count: None,
-        };
-        let float = wgpu::TextureSampleType::Float { filterable: true };
-        let sampler = |binding, ty| wgpu::BindGroupLayoutEntry {
-            binding,
-            visibility: wgpu::ShaderStages::FRAGMENT,
-            ty: wgpu::BindingType::Sampler(ty),
-            count: None,
-        };
-        let uniform_entry = |binding| wgpu::BindGroupLayoutEntry {
-            binding,
-            visibility: wgpu::ShaderStages::FRAGMENT,
-            ty: wgpu::BindingType::Buffer {
-                ty: wgpu::BufferBindingType::Uniform,
-                has_dynamic_offset: false,
-                min_binding_size: None,
-            },
-            count: None,
-        };
-        let layout = device.create_bind_group_layout(&wgpu::BindGroupLayoutDescriptor {
-            label: Some("Shader pack stage"),
-            entries: &[
-                texture(0, float),
-                texture(1, wgpu::TextureSampleType::Depth),
-                texture(2, float),
-                sampler(3, wgpu::SamplerBindingType::Filtering),
-                sampler(4, wgpu::SamplerBindingType::NonFiltering),
-                uniform_entry(5),
-                uniform_entry(6),
-                texture(7, float),
-                texture(8, float),
-                texture(9, wgpu::TextureSampleType::Depth),
-                texture(10, wgpu::TextureSampleType::Depth),
-                sampler(11, wgpu::SamplerBindingType::Comparison),
-                texture(12, float),
-                sampler(13, wgpu::SamplerBindingType::Filtering),
-            ],
-        });
-        let pipeline_layout = device.create_pipeline_layout(&wgpu::PipelineLayoutDescriptor {
-            label: Some("Shader pack stage"),
-            bind_group_layouts: &[Some(&layout)],
-            ..Default::default()
-        });
-        let constants = pack.constants();
-        let scope = device.push_error_scope(wgpu::ErrorFilter::Validation);
-        let stage_count = pack.stages.len();
-        let passes = pack
-            .stages
-            .iter()
-            .enumerate()
-            .map(|(idx, stage)| {
-                let is_last = idx + 1 == stage_count;
-                let target_format = if is_last {
-                    format
-                } else {
-                    stage_format(stage.format.as_deref(), format)
-                };
-                let module = device.create_shader_module(wgpu::ShaderModuleDescriptor {
-                    label: Some(&stage.file),
-                    source: wgpu::ShaderSource::Wgsl(stage.source.as_str().into()),
-                });
-                // Only the overrides a stage declares may be passed to it.
-                let constants: Vec<(&str, f64)> = constants
-                    .iter()
-                    .copied()
-                    .filter(|(key, _)| declares_override(&stage.source, key))
-                    .collect();
-                let pipeline = device.create_render_pipeline(&wgpu::RenderPipelineDescriptor {
-                    label: Some(&stage.file),
-                    layout: Some(&pipeline_layout),
-                    vertex: wgpu::VertexState {
-                        module: &module,
-                        entry_point: Some(VERTEX_ENTRY),
-                        compilation_options: Default::default(),
-                        buffers: &[],
-                    },
-                    primitive: Default::default(),
-                    depth_stencil: None,
-                    multisample: Default::default(),
-                    fragment: Some(wgpu::FragmentState {
-                        module: &module,
-                        entry_point: Some(&stage.entry),
-                        compilation_options: wgpu::PipelineCompilationOptions {
-                            constants: &constants,
-                            ..Default::default()
-                        },
-                        targets: &[Some(wgpu::ColorTargetState {
-                            format: target_format,
-                            blend: None,
-                            write_mask: wgpu::ColorWrites::ALL,
-                        })],
-                    }),
-                    multiview_mask: None,
-                    cache: None,
-                });
-                Pass {
-                    pipeline,
-                    scale: stage.scale,
-                    target_format,
-                    uniform: device.create_buffer(&wgpu::BufferDescriptor {
-                        label: Some("Shader pack frame"),
-                        size: std::mem::size_of::<FrameUniform>() as u64,
-                        usage: wgpu::BufferUsages::UNIFORM | wgpu::BufferUsages::COPY_DST,
-                        mapped_at_creation: false,
-                    }),
-                    uniform_ext: device.create_buffer(&wgpu::BufferDescriptor {
-                        label: Some("Shader pack frame ext"),
-                        size: std::mem::size_of::<FrameExtUniform>() as u64,
-                        usage: wgpu::BufferUsages::UNIFORM | wgpu::BufferUsages::COPY_DST,
-                        mapped_at_creation: false,
-                    }),
-                }
-            })
-            .collect();
-        if let Some(error) = pollster::block_on(scope.pop()) {
-            return Err(error.to_string());
-        }
-        let make_sampler = |filter, address, compare| {
-            device.create_sampler(&wgpu::SamplerDescriptor {
-                label: Some("Shader pack"),
-                address_mode_u: address,
-                address_mode_v: address,
-                address_mode_w: address,
-                mag_filter: filter,
-                min_filter: filter,
-                compare,
-                ..Default::default()
-            })
-        };
-        let noise_view = match &pack.custom_noise {
-            Some(image) => rgba_view(device, queue, "Shader pack noise", image),
-            None => rgba_view(device, queue, "Shader pack noise", &noise()),
-        };
-        let (shadow_res, shadow_dist) = pack.shadow_config();
-        Ok(Self {
-            id: pack.id.clone(),
-            needs_shadow: pack.needs_shadow(),
-            needs_gbuffer: pack.needs_gbuffer(),
-            needs_opaque_depth: pack.needs_opaque_depth(),
-            shadow_res,
-            shadow_dist,
-            layout,
-            linear: make_sampler(
-                wgpu::FilterMode::Linear,
-                wgpu::AddressMode::ClampToEdge,
-                None,
-            ),
-            nearest: make_sampler(
-                wgpu::FilterMode::Nearest,
-                wgpu::AddressMode::ClampToEdge,
-                None,
-            ),
-            repeat: make_sampler(wgpu::FilterMode::Linear, wgpu::AddressMode::Repeat, None),
-            shadow_sampler: make_sampler(
-                wgpu::FilterMode::Linear,
-                wgpu::AddressMode::ClampToEdge,
-                Some(wgpu::CompareFunction::GreaterEqual),
-            ),
-            noise_view,
-            passes,
-            targets: Vec::new(),
-            output: None,
-            world_size: [0, 0],
-            post_generation: u64::MAX,
-            started: std::time::Instant::now(),
-            last: None,
-            frames: 0,
-            previous: None,
-            wetness: SmoothFloat::default(),
-        })
-    }
-
-    /// Run every stage over the world's `color` and `depth` (`size`) and
-    /// return `post`'s bindings of the last stage's output.
-    #[allow(clippy::too_many_arguments)]
-    pub fn run(
-        &mut self,
-        device: &wgpu::Device,
-        queue: &wgpu::Queue,
-        encoder: &mut wgpu::CommandEncoder,
-        color: &wgpu::TextureView,
-        depth: &wgpu::TextureView,
-        size: [u32; 2],
-        post: &super::world_post::Post,
-        mut uniform: FrameUniform,
-        eye_light: [u8; 2],
-    ) -> &wgpu::BindGroup {
-        if self.world_size != size
-            || self.post_generation != post.generation()
-            || self.targets.len() != self.passes.len()
-        {
-            self.world_size = size;
-            self.post_generation = post.generation();
-            self.targets.clear();
-            for pass in &self.passes {
-                let target_size = size.map(|v| ((v as f32 * pass.scale).round() as u32).max(1));
-                let view = device
-                    .create_texture(&wgpu::TextureDescriptor {
-                        label: Some("Shader pack stage"),
-                        size: wgpu::Extent3d {
-                            width: target_size[0],
-                            height: target_size[1],
-                            depth_or_array_layers: 1,
-                        },
-                        mip_level_count: 1,
-                        sample_count: 1,
-                        dimension: wgpu::TextureDimension::D2,
-                        format: pass.target_format,
-                        usage: wgpu::TextureUsages::RENDER_ATTACHMENT
-                            | wgpu::TextureUsages::TEXTURE_BINDING,
-                        view_formats: &[],
-                    })
-                    .create_view(&Default::default());
-                let previous = self.targets.last().map_or(color, |t: &Target| &t.view);
-                let group = device.create_bind_group(&wgpu::BindGroupDescriptor {
-                    label: Some("Shader pack stage"),
-                    layout: &self.layout,
-                    entries: &[
-                        wgpu::BindGroupEntry {
-                            binding: 0,
-                            resource: wgpu::BindingResource::TextureView(color),
-                        },
-                        wgpu::BindGroupEntry {
-                            binding: 1,
-                            resource: wgpu::BindingResource::TextureView(depth),
-                        },
-                        wgpu::BindGroupEntry {
-                            binding: 2,
-                            resource: wgpu::BindingResource::TextureView(previous),
-                        },
-                        wgpu::BindGroupEntry {
-                            binding: 3,
-                            resource: wgpu::BindingResource::Sampler(&self.linear),
-                        },
-                        wgpu::BindGroupEntry {
-                            binding: 4,
-                            resource: wgpu::BindingResource::Sampler(&self.nearest),
-                        },
-                        wgpu::BindGroupEntry {
-                            binding: 5,
-                            resource: pass.uniform.as_entire_binding(),
-                        },
-                        wgpu::BindGroupEntry {
-                            binding: 6,
-                            resource: pass.uniform_ext.as_entire_binding(),
-                        },
-                        wgpu::BindGroupEntry {
-                            binding: 7,
-                            resource: wgpu::BindingResource::TextureView(post.normal()),
-                        },
-                        wgpu::BindGroupEntry {
-                            binding: 8,
-                            resource: wgpu::BindingResource::TextureView(post.material()),
-                        },
-                        wgpu::BindGroupEntry {
-                            binding: 9,
-                            resource: wgpu::BindingResource::TextureView(post.opaque_depth()),
-                        },
-                        wgpu::BindGroupEntry {
-                            binding: 10,
-                            resource: wgpu::BindingResource::TextureView(post.shadow_depth()),
-                        },
-                        wgpu::BindGroupEntry {
-                            binding: 11,
-                            resource: wgpu::BindingResource::Sampler(&self.shadow_sampler),
-                        },
-                        wgpu::BindGroupEntry {
-                            binding: 12,
-                            resource: wgpu::BindingResource::TextureView(&self.noise_view),
-                        },
-                        wgpu::BindGroupEntry {
-                            binding: 13,
-                            resource: wgpu::BindingResource::Sampler(&self.repeat),
-                        },
-                    ],
-                });
-                self.targets.push(Target {
-                    size: target_size,
-                    view,
-                    group,
-                });
-            }
-            let last = &self.targets.last().expect("a pack has a stage").view;
-            self.output = Some(post.bind(device, last));
-        }
-        let now = std::time::Instant::now();
-        let dt = self.last.map_or(0.0, |t| (now - t).as_secs_f32());
-        self.last = Some(now);
-        let wet = self.wetness.update(uniform.weather[0], 60.0, 120.0, dt);
-        let cam = [
-            uniform.camera_position[0],
-            uniform.camera_position[1],
-            uniform.camera_position[2],
-        ];
-        let (prev_view, prev_proj, prev_cam) =
-            self.previous
-                .unwrap_or((uniform.view, uniform.projection, cam));
-        self.previous = Some((uniform.view, uniform.projection, cam));
-        let shadow_view = post.shadow_view;
-        let shadow_proj = post.shadow_proj;
-        let ext = FrameExtUniform {
-            previous_view: prev_view,
-            previous_projection: prev_proj,
-            shadow_view: shadow_view.to_cols_array_2d(),
-            shadow_projection: shadow_proj.to_cols_array_2d(),
-            shadow_inverse_view: shadow_view.inverse().to_cols_array_2d(),
-            shadow_inverse_projection: shadow_proj.inverse().to_cols_array_2d(),
-            previous_camera: [prev_cam[0], prev_cam[1], prev_cam[2], dt],
-            shadow_params: [
-                post.shadow_resolution as f32,
-                post.shadow_distance,
-                0.0,
-                if post.shadow_active { 1.0 } else { 0.0 },
-            ],
-            environment: [
-                f32::from(eye_light[0]) * 16.0,
-                f32::from(eye_light[1]) * 16.0,
-                wet,
-                0.0,
-            ],
-        };
-        uniform.time[0] = self.started.elapsed().as_secs_f32();
-        uniform.time[1] = self.frames as f32;
-        self.frames = self.frames.wrapping_add(1);
-        for (pass, target) in self.passes.iter().zip(&self.targets) {
-            let [w, h] = target.size.map(|v| v as f32);
-            uniform.resolution = [w, h, 1.0 / w, 1.0 / h];
-            queue.write_buffer(&pass.uniform, 0, bytemuck::bytes_of(&uniform));
-            queue.write_buffer(&pass.uniform_ext, 0, bytemuck::bytes_of(&ext));
-            let attachments = [Some(wgpu::RenderPassColorAttachment {
-                view: &target.view,
-                resolve_target: None,
-                depth_slice: None,
-                ops: wgpu::Operations {
-                    load: wgpu::LoadOp::Clear(wgpu::Color::BLACK),
-                    store: wgpu::StoreOp::Store,
-                },
-            })];
-            let mut render = encoder.begin_render_pass(&wgpu::RenderPassDescriptor {
-                label: Some("Shader pack stage"),
-                color_attachments: &attachments,
-                ..Default::default()
-            });
-            render.set_pipeline(&pass.pipeline);
-            render.set_bind_group(0, &target.group, &[]);
-            render.draw(0..3, 0..1);
-        }
-        self.output.as_ref().expect("bound with the targets")
-    }
-}
-
-/// `override <key>` appears in the source (a declaration, not just a use).
-fn declares_override(source: &str, key: &str) -> bool {
-    source.lines().any(|line| {
-        line.trim_start()
-            .strip_prefix("override")
-            .and_then(|rest| rest.trim_start().strip_prefix(key))
-            .is_some_and(|rest| rest.trim_start().starts_with([':', '=']))
-    })
-}
-
-#[cfg(test)]
-mod tests {
-    #[test]
-    fn the_frame_uniform_matches_the_prelude() {
-        // 4 matrices and 12 vectors, as `struct Frame` in the prelude.
-        assert_eq!(std::mem::size_of::<super::FrameUniform>(), 4 * 64 + 12 * 16);
-        let prelude = crate::shader_pack::PRELUDE;
-        let body = prelude.split("struct Frame {").nth(1).unwrap();
-        let body = &body[..body.find('}').unwrap()];
-        assert_eq!(body.matches("mat4x4<f32>").count(), 4);
-        assert_eq!(body.matches("vec4<f32>").count(), 12);
-    }
-    #[test]
-    fn only_declared_overrides_are_passed() {
-        let source =
-            "override saturation: f32 = 1.0;\noverride  vignette = true;\nlet x = saturation_2;";
-        assert!(super::declares_override(source, "saturation"));
-        assert!(super::declares_override(source, "vignette"));
-        assert!(!super::declares_override(source, "saturation_2"));
-        assert!(!super::declares_override(source, "haze"));
-    }
-}
@@ -1,163 +1,25 @@
-//! Resolution scale, FXAA, and shader-pack G-buffer/shadow targets (Horizon
-//! settings): the world renders into its own target at the scaled size, then
-//! one full-screen pass copies or anti-aliases it onto the screen, under the
-//! hand and HUD. For a shader pack that reads them, `Post` also keeps:
-//! - `opaque_depth`: the depth before translucent terrain (water, stained
-//!   glass, ice) draws, a Java pack's `depthtex1`/`depthtex2`;
-//! - `normal` and `material`, an api 2 pack's `scene_normal` and
-//!   `scene_material`: surface normals and material properties
-//!   reconstructed from depth and scene colour;
-//! - `shadow_depth`, an api 2 pack's: the sun/moon shadow map and its
-//!   light-space `shadow_view` and `shadow_proj` matrices.
-//!
-//! With none of them on, the world renders straight to the screen as before.
-
-use super::pack_stages::FrameUniform;
-use glam::{Mat4, Vec3};
-
-const GBUFFER_WGSL: &str = r#"
-struct GbufferParams {
-    inverse_view: mat4x4<f32>,
-    inverse_projection: mat4x4<f32>,
-    resolution: vec4<f32>,
-    // x: eye block light (0..1), y: eye sky light (0..1), z: wetness (0..1), w: sun elevation
-    env: vec4<f32>,
-}
-
-@group(0) @binding(0) var world_color: texture_2d<f32>;
-@group(0) @binding(1) var world_depth: texture_depth_2d;
-@group(0) @binding(2) var opaque_depth: texture_depth_2d;
-@group(0) @binding(3) var nearest_sampler: sampler;
-@group(0) @binding(4) var<uniform> params: GbufferParams;
-
-struct VsOut {
-    @builtin(position) clip: vec4<f32>,
-    @location(0) uv: vec2<f32>,
-}
-
-@vertex
-fn vs_gbuffer(@builtin(vertex_index) i: u32) -> VsOut {
-    let p = vec2<f32>(f32((i << 1u) & 2u), f32(i & 2u));
-    var out: VsOut;
-    out.clip = vec4<f32>(p * 2.0 - 1.0, 0.0, 1.0);
-    out.uv = vec2<f32>(p.x, 1.0 - p.y);
-    return out;
-}
-
-struct GbufferOut {
-    @location(0) normal: vec4<f32>,
-    @location(1) material: vec4<f32>,
-}
-
-fn world_pos(uv: vec2<f32>, d: f32) -> vec3<f32> {
-    let v = params.inverse_projection * vec4<f32>(uv.x * 2.0 - 1.0, 1.0 - uv.y * 2.0, d, 1.0);
-    let view = v.xyz / max(v.w, 1e-6);
-    return (params.inverse_view * vec4<f32>(view, 1.0)).xyz;
-}
-
-@fragment
-fn fs_gbuffer(in: VsOut) -> GbufferOut {
-    let d_all = textureSampleLevel(world_depth, nearest_sampler, in.uv, 0);
-    let d_opq = textureSampleLevel(opaque_depth, nearest_sampler, in.uv, 0);
-    let color = textureSampleLevel(world_color, nearest_sampler, in.uv, 0.0);
-    var out: GbufferOut;
-    if d_all <= 0.0 && d_opq <= 0.0 {
-        out.normal = vec4<f32>(0.5, 1.0, 0.5, 0.0);
-        out.material = vec4<f32>(0.0, params.env.y, 0.0, 1.0);
-        return out;
-    }
-    let d = select(d_all, d_opq, d_opq > 0.0);
-    let step_uv = params.resolution.zw;
-    let p0 = world_pos(in.uv, d);
-    let uv_r = clamp(in.uv + vec2<f32>(step_uv.x, 0.0), vec2<f32>(0.0), vec2<f32>(1.0));
-    let uv_l = clamp(in.uv - vec2<f32>(step_uv.x, 0.0), vec2<f32>(0.0), vec2<f32>(1.0));
-    let uv_d = clamp(in.uv + vec2<f32>(0.0, step_uv.y), vec2<f32>(0.0), vec2<f32>(1.0));
-    let uv_u = clamp(in.uv - vec2<f32>(0.0, step_uv.y), vec2<f32>(0.0), vec2<f32>(1.0));
-    let dr = textureSampleLevel(opaque_depth, nearest_sampler, uv_r, 0);
-    let dl = textureSampleLevel(opaque_depth, nearest_sampler, uv_l, 0);
-    let dd = textureSampleLevel(opaque_depth, nearest_sampler, uv_d, 0);
-    let du = textureSampleLevel(opaque_depth, nearest_sampler, uv_u, 0);
-    let dx = select(world_pos(uv_r, dr) - p0, p0 - world_pos(uv_l, dl), abs(dl - d) < abs(dr - d));
-    let dy = select(world_pos(uv_d, dd) - p0, p0 - world_pos(uv_u, du), abs(du - d) < abs(dd - d));
-    let raw_n = cross(dy, dx);
-    let n_len = length(raw_n);
-    let n = select(vec3<f32>(0.0, 1.0, 0.0), raw_n / max(n_len, 1e-6), n_len > 1e-6);
-    // Reversed depth: closer translucent geometry has larger depth than opaque geometry.
-    let is_translucent = select(0.0, 1.0, d_all > d_opq + 1e-5);
-    let luma = dot(color.rgb, vec3<f32>(0.2126, 0.7152, 0.0722));
-    let block_light = clamp(max(params.env.x, smoothstep(0.65, 0.98, luma)), 0.0, 1.0);
-    let roughness = select(clamp(0.85 - params.env.z * 0.45, 0.1, 1.0), 0.05, is_translucent > 0.5);
-    out.normal = vec4<f32>(n * 0.5 + 0.5, 1.0);
-    out.material = vec4<f32>(block_light, params.env.y, is_translucent, roughness);
-    return out;
-}
-"#;
-
-#[repr(C)]
-#[derive(Clone, Copy, Default, bytemuck::Pod, bytemuck::Zeroable)]
-struct GbufferUniform {
-    inverse_view: [[f32; 4]; 4],
-    inverse_projection: [[f32; 4]; 4],
-    resolution: [f32; 4],
-    env: [f32; 4],
-}
-
-/// What the frame's shader pack reads beyond the world's colour and depth:
-/// `Post` keeps these targets only while one does.
-#[derive(Clone, Copy, Debug, Default, PartialEq, Eq)]
-pub struct Extras {
-    pub opaque_depth: bool,
-    pub gbuffer: bool,
-}
+//! Resolution scale and FXAA (Horizon settings): the world renders into its
+//! own target at the scaled size, then one full-screen pass copies or
+//! anti-aliases it onto the screen, under the hand and HUD. With neither on,
+//! the world renders straight to the screen.

 struct WorldTarget {
    size: [u32; 2],
-    extras: Extras,
    color: wgpu::TextureView,
-    depth_tex: wgpu::Texture,
    depth: wgpu::TextureView,
-    /// With `extras.opaque_depth` or `extras.gbuffer` (which reads it).
-    opaque_depth: Option<(wgpu::Texture, wgpu::TextureView)>,
-    gbuffer: Option<Gbuffer>,
    group: wgpu::BindGroup,
-    opaque_captured: bool,
-}
-
-struct Gbuffer {
-    normal: wgpu::TextureView,
-    material: wgpu::TextureView,
-    group: wgpu::BindGroup,
-}
-
-struct ShadowTarget {
-    resolution: u32,
-    depth: wgpu::TextureView,
 }

 pub struct Post {
    layout: wgpu::BindGroupLayout,
    sampler: wgpu::Sampler,
-    nearest: wgpu::Sampler,
    copy: wgpu::RenderPipeline,
    fxaa: wgpu::RenderPipeline,
-    gbuffer_layout: wgpu::BindGroupLayout,
-    gbuffer_pipeline: wgpu::RenderPipeline,
-    gbuffer_uniform: wgpu::Buffer,
    format: wgpu::TextureFormat,
    /// World resolution relative to the window (0.5..=2.0).
    pub scale: f32,
    pub antialias: bool,
    target: Option<WorldTarget>,
-    shadow: Option<ShadowTarget>,
-    /// Bumped whenever a target is made: bindings of the old ones are stale.
-    generation: u64,
-    fallback_shadow: wgpu::TextureView,
-    fallback_color: wgpu::TextureView,
-    pub shadow_view: Mat4,
-    pub shadow_proj: Mat4,
-    pub shadow_distance: f32,
-    pub shadow_resolution: u32,
-    pub shadow_active: bool,
 }

 impl Post {
@@ -225,192 +87,31 @@ impl Post {
            min_filter: wgpu::FilterMode::Linear,
            ..Default::default()
        });
-        let nearest = device.create_sampler(&wgpu::SamplerDescriptor {
-            label: Some("Horizon post nearest"),
-            mag_filter: wgpu::FilterMode::Nearest,
-            min_filter: wgpu::FilterMode::Nearest,
-            ..Default::default()
-        });
-
-        let gbuffer_shader = device.create_shader_module(wgpu::ShaderModuleDescriptor {
-            label: Some("Horizon gbuffer"),
-            source: wgpu::ShaderSource::Wgsl(GBUFFER_WGSL.into()),
-        });
-        let gbuffer_layout = device.create_bind_group_layout(&wgpu::BindGroupLayoutDescriptor {
-            label: Some("Horizon gbuffer layout"),
-            entries: &[
-                wgpu::BindGroupLayoutEntry {
-                    binding: 0,
-                    visibility: wgpu::ShaderStages::FRAGMENT,
-                    ty: wgpu::BindingType::Texture {
-                        sample_type: wgpu::TextureSampleType::Float { filterable: true },
-                        view_dimension: wgpu::TextureViewDimension::D2,
-                        multisampled: false,
-                    },
-                    count: None,
-                },
-                wgpu::BindGroupLayoutEntry {
-                    binding: 1,
-                    visibility: wgpu::ShaderStages::FRAGMENT,
-                    ty: wgpu::BindingType::Texture {
-                        sample_type: wgpu::TextureSampleType::Depth,
-                        view_dimension: wgpu::TextureViewDimension::D2,
-                        multisampled: false,
-                    },
-                    count: None,
-                },
-                wgpu::BindGroupLayoutEntry {
-                    binding: 2,
-                    visibility: wgpu::ShaderStages::FRAGMENT,
-                    ty: wgpu::BindingType::Texture {
-                        sample_type: wgpu::TextureSampleType::Depth,
-                        view_dimension: wgpu::TextureViewDimension::D2,
-                        multisampled: false,
-                    },
-                    count: None,
-                },
-                wgpu::BindGroupLayoutEntry {
-                    binding: 3,
-                    visibility: wgpu::ShaderStages::FRAGMENT,
-                    ty: wgpu::BindingType::Sampler(wgpu::SamplerBindingType::NonFiltering),
-                    count: None,
-                },
-                wgpu::BindGroupLayoutEntry {
-                    binding: 4,
-                    visibility: wgpu::ShaderStages::FRAGMENT,
-                    ty: wgpu::BindingType::Buffer {
-                        ty: wgpu::BufferBindingType::Uniform,
-                        has_dynamic_offset: false,
-                        min_binding_size: None,
-                    },
-                    count: None,
-                },
-            ],
-        });
-        let gbuffer_pipe_layout = device.create_pipeline_layout(&wgpu::PipelineLayoutDescriptor {
-            label: Some("Horizon gbuffer"),
-            bind_group_layouts: &[Some(&gbuffer_layout)],
-            ..Default::default()
-        });
-        let gbuffer_pipeline = device.create_render_pipeline(&wgpu::RenderPipelineDescriptor {
-            label: Some("Horizon gbuffer"),
-            layout: Some(&gbuffer_pipe_layout),
-            vertex: wgpu::VertexState {
-                module: &gbuffer_shader,
-                entry_point: Some("vs_gbuffer"),
-                compilation_options: Default::default(),
-                buffers: &[],
-            },
-            primitive: Default::default(),
-            depth_stencil: None,
-            multisample: Default::default(),
-            fragment: Some(wgpu::FragmentState {
-                module: &gbuffer_shader,
-                entry_point: Some("fs_gbuffer"),
-                compilation_options: Default::default(),
-                targets: &[
-                    Some(wgpu::ColorTargetState {
-                        format: wgpu::TextureFormat::Rgba8Unorm,
-                        blend: None,
-                        write_mask: wgpu::ColorWrites::ALL,
-                    }),
-                    Some(wgpu::ColorTargetState {
-                        format: wgpu::TextureFormat::Rgba8Unorm,
-                        blend: None,
-                        write_mask: wgpu::ColorWrites::ALL,
-                    }),
-                ],
-            }),
-            multiview_mask: None,
-            cache: None,
-        });
-        let gbuffer_uniform = device.create_buffer(&wgpu::BufferDescriptor {
-            label: Some("Horizon gbuffer uniform"),
-            size: std::mem::size_of::<GbufferUniform>() as u64,
-            usage: wgpu::BufferUsages::UNIFORM | wgpu::BufferUsages::COPY_DST,
-            mapped_at_creation: false,
-        });
-        let fallback_shadow = device
-            .create_texture(&wgpu::TextureDescriptor {
-                label: Some("Horizon fallback shadow"),
-                size: wgpu::Extent3d {
-                    width: 1,
-                    height: 1,
-                    depth_or_array_layers: 1,
-                },
-                mip_level_count: 1,
-                sample_count: 1,
-                dimension: wgpu::TextureDimension::D2,
-                format: wgpu::TextureFormat::Depth32Float,
-                usage: wgpu::TextureUsages::RENDER_ATTACHMENT
-                    | wgpu::TextureUsages::TEXTURE_BINDING,
-                view_formats: &[],
-            })
-            .create_view(&Default::default());
-        let fallback_color = device
-            .create_texture(&wgpu::TextureDescriptor {
-                label: Some("Horizon fallback gbuffer"),
-                size: wgpu::Extent3d {
-                    width: 1,
-                    height: 1,
-                    depth_or_array_layers: 1,
-                },
-                mip_level_count: 1,
-                sample_count: 1,
-                dimension: wgpu::TextureDimension::D2,
-                format: wgpu::TextureFormat::Rgba8Unorm,
-                usage: wgpu::TextureUsages::RENDER_ATTACHMENT
-                    | wgpu::TextureUsages::TEXTURE_BINDING,
-                view_formats: &[],
-            })
-            .create_view(&Default::default());
        Self {
            copy: pipeline("fs_copy"),
            fxaa: pipeline("fs_fxaa"),
            layout,
            sampler,
-            nearest,
-            gbuffer_layout,
-            gbuffer_pipeline,
-            gbuffer_uniform,
            format,
            scale: 1.0,
            antialias: false,
            target: None,
-            shadow: None,
-            generation: 0,
-            fallback_shadow,
-            fallback_color,
-            shadow_view: Mat4::IDENTITY,
-            shadow_proj: Mat4::IDENTITY,
-            shadow_distance: 128.0,
-            shadow_resolution: 2048,
-            shadow_active: false,
        }
    }

    /// The world's colour and depth targets this frame, or `None` to draw
-    /// it straight to the screen. `pack`: a shader pack runs this frame,
-    /// reading `extras`.
+    /// it straight to the screen.
    pub fn prepare(
        &mut self,
        device: &wgpu::Device,
        window: [u32; 2],
-        pack: bool,
-        extras: Extras,
    ) -> Option<(wgpu::TextureView, wgpu::TextureView)> {
-        if self.scale == 1.0 && !self.antialias && !pack {
+        if self.scale == 1.0 && !self.antialias {
            self.target = None;
-            self.shadow_active = false;
            return None;
        }
        let size = window.map(|v| ((v as f32 * self.scale).round() as u32).clamp(1, 8192));
-        if self
-            .target
-            .as_ref()
-            .is_none_or(|t| t.size != size || t.extras != extras)
-        {
-            self.generation += 1;
+        if self.target.as_ref().is_none_or(|t| t.size != size) {
            let extent = wgpu::Extent3d {
                width: size[0],
                height: size[1],
@@ -434,273 +135,26 @@ impl Post {
                wgpu::TextureUsages::RENDER_ATTACHMENT | wgpu::TextureUsages::TEXTURE_BINDING,
            )
            .create_view(&Default::default());
-            let depth_tex = make_tex(
+            // TEXTURE_BINDING: occlusion culling reads it.
+            let depth = make_tex(
                "Scaled world depth",
                wgpu::TextureFormat::Depth32Float,
-                wgpu::TextureUsages::RENDER_ATTACHMENT
-                    | wgpu::TextureUsages::TEXTURE_BINDING
-                    | wgpu::TextureUsages::COPY_SRC,
-            );
-            let depth = depth_tex.create_view(&Default::default());
-            let opaque_depth = (extras.opaque_depth || extras.gbuffer).then(|| {
-                let tex = make_tex(
-                    "Opaque world depth",
-                    wgpu::TextureFormat::Depth32Float,
-                    wgpu::TextureUsages::TEXTURE_BINDING | wgpu::TextureUsages::COPY_DST,
-                );
-                let view = tex.create_view(&Default::default());
-                (tex, view)
-            });
-            let gbuffer = opaque_depth
-                .as_ref()
-                .filter(|_| extras.gbuffer)
-                .map(|(_, opaque)| {
-                    let color_target = |label| {
-                        make_tex(
-                            label,
-                            wgpu::TextureFormat::Rgba8Unorm,
-                            wgpu::TextureUsages::RENDER_ATTACHMENT
-                                | wgpu::TextureUsages::TEXTURE_BINDING,
-                        )
-                        .create_view(&Default::default())
-                    };
-                    let group = device.create_bind_group(&wgpu::BindGroupDescriptor {
-                        label: Some("Horizon gbuffer"),
-                        layout: &self.gbuffer_layout,
-                        entries: &[
-                            wgpu::BindGroupEntry {
-                                binding: 0,
-                                resource: wgpu::BindingResource::TextureView(&color),
-                            },
-                            wgpu::BindGroupEntry {
-                                binding: 1,
-                                resource: wgpu::BindingResource::TextureView(&depth),
-                            },
-                            wgpu::BindGroupEntry {
-                                binding: 2,
-                                resource: wgpu::BindingResource::TextureView(opaque),
-                            },
-                            wgpu::BindGroupEntry {
-                                binding: 3,
-                                resource: wgpu::BindingResource::Sampler(&self.nearest),
-                            },
-                            wgpu::BindGroupEntry {
-                                binding: 4,
-                                resource: self.gbuffer_uniform.as_entire_binding(),
-                            },
-                        ],
-                    });
-                    Gbuffer {
-                        normal: color_target("World G-buffer normal"),
-                        material: color_target("World G-buffer material"),
-                        group,
-                    }
-                });
+                wgpu::TextureUsages::RENDER_ATTACHMENT | wgpu::TextureUsages::TEXTURE_BINDING,
+            )
+            .create_view(&Default::default());
            let group = self.bind(device, &color);
            self.target = Some(WorldTarget {
                size,
-                extras,
                color,
-                depth_tex,
                depth,
-                opaque_depth,
-                gbuffer,
                group,
-                opaque_captured: false,
            });
        }
-        if let Some(t) = &mut self.target {
-            t.opaque_captured = false;
-        }
        self.target
            .as_ref()
            .map(|t| (t.color.clone(), t.depth.clone()))
    }

-    /// Prepare the directional sun/moon shadow map target and compute its
-    /// camera-relative orthographic `shadow_view` and `shadow_proj` matrices.
-    pub fn prepare_shadow(
-        &mut self,
-        device: &wgpu::Device,
-        resolution: u32,
-        distance: f32,
-        sun_dir: Vec3,
-        moon_dir: Vec3,
-    ) -> &wgpu::TextureView {
-        let resolution = resolution.clamp(256, 4096);
-        let distance = distance.clamp(16.0, 512.0);
-        if self
-            .shadow
-            .as_ref()
-            .is_none_or(|s| s.resolution != resolution)
-        {
-            let depth = device
-                .create_texture(&wgpu::TextureDescriptor {
-                    label: Some("Horizon shadow map"),
-                    size: wgpu::Extent3d {
-                        width: resolution,
-                        height: resolution,
-                        depth_or_array_layers: 1,
-                    },
-                    mip_level_count: 1,
-                    sample_count: 1,
-                    dimension: wgpu::TextureDimension::D2,
-                    format: wgpu::TextureFormat::Depth32Float,
-                    usage: wgpu::TextureUsages::RENDER_ATTACHMENT
-                        | wgpu::TextureUsages::TEXTURE_BINDING,
-                    view_formats: &[],
-                })
-                .create_view(&Default::default());
-            self.shadow = Some(ShadowTarget { resolution, depth });
-            self.generation += 1;
-        }
-        let light_dir = if sun_dir.y >= -0.05 {
-            sun_dir.normalize_or_zero()
-        } else {
-            moon_dir.normalize_or_zero()
-        };
-        let dir = if light_dir.length_squared() > 1e-4 {
-            light_dir
-        } else {
-            Vec3::Y
-        };
-        let up = if dir.y.abs() > 0.99 { Vec3::Z } else { Vec3::Y };
-        self.shadow_view = Mat4::look_at_rh(dir * distance, Vec3::ZERO, up);
-        // Reversed-depth orthographic projection for the world's GreaterEqual
-        // pipelines (near maps to 1.0, far maps to 0.0), and standard 0..1
-        // projection for shader sampling.
-        self.shadow_proj = Mat4::orthographic_rh(
-            -distance,
-            distance,
-            -distance,
-            distance,
-            distance * 2.5,
-            0.05,
-        );
-        self.shadow_distance = distance;
-        self.shadow_resolution = resolution;
-        self.shadow_active = true;
-        &self.shadow.as_ref().expect("created above").depth
-    }
-
-    /// Snapshot `world_depth` into `opaque_depth` (`depthtex1`/`depthtex2`)
-    /// right before translucent water and weather draw.
-    pub fn capture_opaque_depth(&mut self, encoder: &mut wgpu::CommandEncoder) {
-        let Some(t) = &mut self.target else { return };
-        let Some((opaque, _)) = &t.opaque_depth else {
-            return;
-        };
-        encoder.copy_texture_to_texture(
-            t.depth_tex.as_image_copy(),
-            opaque.as_image_copy(),
-            t.depth_tex.size(),
-        );
-        t.opaque_captured = true;
-    }
-
-    /// Reconstruct the G-buffer `normal` and `material` textures after the
-    /// world pass finishes (with `Extras::gbuffer`).
-    pub fn build_gbuffer(
-        &mut self,
-        queue: &wgpu::Queue,
-        encoder: &mut wgpu::CommandEncoder,
-        frame: &FrameUniform,
-        eye_light: [u8; 2],
-        wetness: f32,
-    ) {
-        if !self.target.as_ref().is_some_and(|t| t.opaque_captured) {
-            self.capture_opaque_depth(encoder);
-        }
-        let Some(t) = &self.target else { return };
-        let Some(gbuffer) = &t.gbuffer else { return };
-        let [w, h] = t.size.map(|v| v.max(1) as f32);
-        let uniform = GbufferUniform {
-            inverse_view: frame.inverse_view,
-            inverse_projection: frame.inverse_projection,
-            resolution: [w, h, 1.0 / w, 1.0 / h],
-            env: [
-                f32::from(eye_light[0]) / 15.0,
-                f32::from(eye_light[1]) / 15.0,
-                wetness,
-                frame.sun[1],
-            ],
-        };
-        queue.write_buffer(&self.gbuffer_uniform, 0, bytemuck::bytes_of(&uniform));
-        let attachments = [
-            Some(wgpu::RenderPassColorAttachment {
-                view: &gbuffer.normal,
-                resolve_target: None,
-                depth_slice: None,
-                ops: wgpu::Operations {
-                    load: wgpu::LoadOp::Clear(wgpu::Color::BLACK),
-                    store: wgpu::StoreOp::Store,
-                },
-            }),
-            Some(wgpu::RenderPassColorAttachment {
-                view: &gbuffer.material,
-                resolve_target: None,
-                depth_slice: None,
-                ops: wgpu::Operations {
-                    load: wgpu::LoadOp::Clear(wgpu::Color::BLACK),
-                    store: wgpu::StoreOp::Store,
-                },
-            }),
-        ];
-        let mut pass = encoder.begin_render_pass(&wgpu::RenderPassDescriptor {
-            label: Some("Horizon gbuffer"),
-            color_attachments: &attachments,
-            ..Default::default()
-        });
-        pass.set_pipeline(&self.gbuffer_pipeline);
-        pass.set_bind_group(0, &gbuffer.group, &[]);
-        pass.draw(0..3, 0..1);
-    }
-
-    /// The world target's size, once `prepare` made one.
-    pub fn size(&self) -> Option<[u32; 2]> {
-        self.target.as_ref().map(|t| t.size)
-    }
-
-    /// Changes whenever `prepare` or `prepare_shadow` makes new targets:
-    /// bindings made from the views below must be made again.
-    pub fn generation(&self) -> u64 {
-        self.generation
-    }
-
-    /// The depth before translucent geometry (`capture_opaque_depth`), or
-    /// the world's depth when nothing reads it.
-    pub fn opaque_depth(&self) -> &wgpu::TextureView {
-        match &self.target {
-            Some(WorldTarget {
-                opaque_depth: Some((_, view)),
-                ..
-            }) => view,
-            Some(t) => &t.depth,
-            None => &self.fallback_shadow,
-        }
-    }
-
-    /// Reconstructed world-space normals (`scene_normal`).
-    pub fn normal(&self) -> &wgpu::TextureView {
-        self.gbuffer().map_or(&self.fallback_color, |g| &g.normal)
-    }
-
-    /// Reconstructed material and light (`scene_material`).
-    pub fn material(&self) -> &wgpu::TextureView {
-        self.gbuffer().map_or(&self.fallback_color, |g| &g.material)
-    }
-
-    fn gbuffer(&self) -> Option<&Gbuffer> {
-        self.target.as_ref()?.gbuffer.as_ref()
-    }
-
-    /// The sun/moon shadow map (`shadow_depth` of api 2 packs).
-    pub fn shadow_depth(&self) -> &wgpu::TextureView {
-        self.shadow
-            .as_ref()
-            .map_or(&self.fallback_shadow, |s| &s.depth)
-    }
-
    /// Bindings that copy (or anti-alias) `view` onto the screen in `finish_with`.
    pub fn bind(&self, device: &wgpu::Device, view: &wgpu::TextureView) -> wgpu::BindGroup {
        device.create_bind_group(&wgpu::BindGroupDescriptor {
@@ -227,8 +227,6 @@ pub struct Graphics {
    pub far_detail: FarDetail,
    /// Skip sections hidden behind closed ones (vanilla's occlusion graph).
    pub cave_culling: bool,
-    /// Hide shared leaf and mangrove-root faces, reducing foliage density.
-    pub cull_leaves: bool,
    /// Skip drawing entities hidden behind opaque terrain.
    pub entity_culling: bool,
    /// Meshed sections uploaded per frame; 0 uploads all that are ready.
@@ -252,9 +250,6 @@ pub struct Graphics {
    /// or behind other windows, and half the worker threads. Off by default;
    /// it changes when frames are drawn, never what they show or the ticks.
    pub battery: bool,
-    /// The Horizon shader pack in `shaderpacks/` (its folder name); empty:
-    /// none, the vanilla picture (docs/shader-packs.md).
-    pub shader_pack: String,
    /// The graphics API (Windows only; see `GraphicsApi`).
    pub api: GraphicsApi,
 }
@@ -265,7 +260,6 @@ impl Default for Graphics {
            lod_distance: 0,
            far_detail: FarDetail::Full,
            cave_culling: true,
-            cull_leaves: false,
            entity_culling: false,
            chunk_updates: 0,
            upload_budget_kib: 0,
@@ -280,7 +274,6 @@ impl Default for Graphics {
            resolution_scale: 100,
            fxaa: false,
            battery: false,
-            shader_pack: String::new(),
            api: GraphicsApi::Auto,
        }
    }
@@ -312,7 +305,6 @@ impl Graphics {
                "lodDistance" => g.lod_distance = number(g.lod_distance).min(1024),
                "farDetail" => g.far_detail = FarDetail::parse(value),
                "caveCulling" => g.cave_culling = flag(g.cave_culling),
-                "cullLeaves" => g.cull_leaves = flag(g.cull_leaves),
                "entityCulling" => g.entity_culling = flag(g.entity_culling),
                "chunkUpdates" => g.chunk_updates = number(g.chunk_updates).min(512),
                "uploadBudgetKiB" => g.upload_budget_kib = number(g.upload_budget_kib).min(65536),
@@ -332,7 +324,6 @@ impl Graphics {
                "resolutionScale" => g.resolution_scale = number(g.resolution_scale).clamp(50, 200),
                "fxaa" => g.fxaa = flag(g.fxaa),
                "batteryMode" => g.battery = flag(g.battery),
-                "shaderPack" => g.shader_pack = value.to_string(),
                "graphicsApi" => g.api = GraphicsApi::from_name(value).unwrap_or_default(),
                "overlay" => {
                    g.overlay = match value {
@@ -348,12 +339,11 @@ impl Graphics {
    }
    pub fn serialize(&self) -> String {
        format!(
-            "preset:{}\nlodDistance:{}\nfarDetail:{}\ncaveCulling:{}\ncullLeaves:{}\nentityCulling:{}\nchunkUpdates:{}\nuploadBudgetKiB:{}\nsky:{}\nfog:{}\nweather:{}\nanimatedTextures:{}\npresentMode:{}\nframePacing:{}\nworkers:{}\noverlay:{}\nresolutionScale:{}\nfxaa:{}\nbatteryMode:{}\nshaderPack:{}\ngraphicsApi:{}\n",
+            "preset:{}\nlodDistance:{}\nfarDetail:{}\ncaveCulling:{}\nentityCulling:{}\nchunkUpdates:{}\nuploadBudgetKiB:{}\nsky:{}\nfog:{}\nweather:{}\nanimatedTextures:{}\npresentMode:{}\nframePacing:{}\nworkers:{}\noverlay:{}\nresolutionScale:{}\nfxaa:{}\nbatteryMode:{}\ngraphicsApi:{}\n",
            self.preset.name(),
            self.lod_distance,
            self.far_detail.name(),
            bool_text(self.cave_culling),
-            bool_text(self.cull_leaves),
            bool_text(self.entity_culling),
            self.chunk_updates,
            self.upload_budget_kib,
@@ -375,7 +365,6 @@ impl Graphics {
            self.resolution_scale,
            bool_text(self.fxaa),
            bool_text(self.battery),
-            self.shader_pack,
            self.api.name(),
        )
    }
@@ -454,7 +443,6 @@ mod tests {
            lod_distance: 256,
            far_detail: FarDetail::Reduced,
            cave_culling: false,
-            cull_leaves: true,
            entity_culling: true,
            chunk_updates: 12,
            upload_budget_kib: 4096,
@@ -469,15 +457,19 @@ mod tests {
            resolution_scale: 75,
            fxaa: true,
            battery: true,
-            shader_pack: "horizon-sample".into(),
            api: GraphicsApi::Dx12,
        };
        assert_eq!(Graphics::parse(&g.serialize()), g);
        assert_eq!(Graphics::parse(""), Graphics::default());
-        // The old menus' Simple / Advanced choice is ignored.
+        // The old menus' Simple / Advanced choice is ignored, and so is the
+        // shader pack older versions saved.
        assert_eq!(Graphics::parse("level:advanced\n"), Graphics::default());
        assert_eq!(
-            Graphics::parse("workers:abc\nsky:maybe\ncullLeaves:maybe\nentityCulling:maybe\n"),
+            Graphics::parse("shaderPack:Pack.zip\n"),
+            Graphics::default()
+        );
+        assert_eq!(
+            Graphics::parse("workers:abc\nsky:maybe\ncullLeaves:true\nentityCulling:maybe\n"),
            Graphics::default()
        );
    }
@@ -24,7 +24,6 @@ pub enum H {
    LodDistance,
    FarDetail,
    CaveCulling,
-    CullLeaves,
    EntityCulling,
    ChunkUpdates,
    UploadBudget,
@@ -39,7 +38,6 @@ pub enum H {
    ResolutionScale,
    Antialiasing,
    BatteryMode,
-    ShaderPack,
    GraphicsApi,
 }

@@ -112,18 +110,13 @@ pub fn rows(level: Level) -> Vec<Row> {
        "Waits for the display's refresh: no tearing, a little latency.",
    );
    let gui = v(Opt::GuiScale, None, "Size of menus and the HUD.");
-    let shader_pack = h(
-        H::ShaderPack,
-        High,
-        "Redraws the world with a pack from the shaderpacks folder. Off is vanilla.",
-    );
    let preset = h(
        H::Preset,
        None,
        "Sets the options below together. Changing one makes it Custom.",
    );
    let mut rows = match level {
-        Level::Simple => vec![preset, render, lod, far, fov, fps, vsync, gui, shader_pack],
+        Level::Simple => vec![preset, render, lod, far, fov, fps, vsync, gui],
        Level::Advanced => vec![
            Row::Header("Rendering"),
            render,
@@ -144,11 +137,6 @@ pub fn rows(level: Level) -> Vec<Row> {
                Saves,
                "Skips terrain hidden behind closed sections. Off costs a lot.",
            ),
-            h(
-                H::CullLeaves,
-                None,
-                "Hides shared leaf and mangrove root faces; foliage can look less dense.",
-            ),
            h(
                H::EntityCulling,
                None,
@@ -251,7 +239,6 @@ pub fn rows(level: Level) -> Vec<Row> {
                None,
                "Lowers the frame rate when minimised, or idle too.",
            ),
-            shader_pack,
            Row::Header("Preferences"),
            v(Opt::ViewBobbing, None, "Sways the view while walking."),
            v(Opt::ChunkFade, None, "Fades newly loaded chunks in."),
@@ -350,7 +337,6 @@ impl H {
            },
            H::FarDetail => labelled("Far Detail", g.far_detail.label()),
            H::CaveCulling => labelled("Cave Culling", on_off(g.cave_culling)),
-            H::CullLeaves => labelled("Cull Leaves", on_off(g.cull_leaves)),
            H::EntityCulling => labelled("Entity Culling", on_off(g.entity_culling)),
            H::ChunkUpdates => match g.chunk_updates {
                0 => labelled("Chunk Updates", "Unlimited"),
@@ -381,10 +367,6 @@ impl H {
            H::Antialiasing => labelled("Anti-aliasing", if g.fxaa { "FXAA" } else { "Off" }),
            H::BatteryMode => labelled("Battery Mode", on_off(g.battery)),
            H::GraphicsApi => labelled("Graphics API", g.api.label()),
-            H::ShaderPack => match g.shader_pack.as_str() {
-                "" => labelled("Shader Pack", "Off"),
-                id => labelled("Shader Pack", id),
-            },
            H::Overlay => labelled(
                "Performance Overlay",
                match g.overlay {
@@ -429,7 +411,6 @@ impl H {
                g.far_detail = step(&[FarDetail::Full, FarDetail::Reduced], g.far_detail, back)
            }
            H::CaveCulling => g.cave_culling = !g.cave_culling,
-            H::CullLeaves => g.cull_leaves = !g.cull_leaves,
            H::EntityCulling => g.entity_culling = !g.entity_culling,
            H::Sky => g.sky = !g.sky,
            H::Fog => g.fog = !g.fog,
@@ -466,7 +447,6 @@ impl Item {
        let g = &s.horizon;
        Some(match self {
            Item::Horizon(H::CaveCulling) => g.cave_culling,
-            Item::Horizon(H::CullLeaves) => g.cull_leaves,
            Item::Horizon(H::EntityCulling) => g.entity_culling,
            Item::Horizon(H::Sky) => g.sky,
            Item::Horizon(H::Fog) => g.fog,
@@ -527,7 +507,6 @@ impl Item {
                    | H::PresentMode
                    | H::Workers
                    | H::BatteryMode
-                    | H::ShaderPack
                    | H::GraphicsApi
            ) | Item::Vanilla(
                Opt::GuiScale
@@ -557,8 +536,6 @@ pub enum Action {
    Changed,
    OpenAdvanced,
    OpenSimple,
-    /// The Shader Pack row: the Shader Packs page (where packs are picked).
-    OpenShaderPacks,
    Done,
 }

@@ -784,9 +761,6 @@ impl GraphicsUi {
            }
            return match wd.target {
                Target::Button(action) => vec![Action::ButtonClick, action],
-                Target::Item(Item::Horizon(H::ShaderPack)) => {
-                    vec![Action::ButtonClick, Action::OpenShaderPacks]
-                }
                Target::Item(item) => {
                    if item.slider(s).is_some() {
                        self.dragging = Some(item);
@@ -994,44 +968,6 @@ mod tests {
        );
    }

-    #[test]
-    fn the_shader_pack_row_is_off_by_default_and_outside_presets() {
-        let mut s = Settings::default();
-        let row = Item::Horizon(H::ShaderPack);
-        assert_eq!(row.label(&s).plain(), "Shader Pack: Off");
-        assert!(
-            rows(Level::Advanced)
-                .iter()
-                .any(|r| matches!(r, Row::Setting(x) if x.item == row))
-        );
-        s.horizon.shader_pack = "horizon-sample".into();
-        assert_eq!(row.label(&s).plain(), "Shader Pack: horizon-sample");
-        // The row opens the Shader Packs page, where packs are picked.
-        let mut ui = GraphicsUi::default();
-        let find = |ui: &mut GraphicsUi| {
-            let (widgets, ..) = ui.layout(Level::Advanced, 854.0, 480.0);
-            widgets
-                .into_iter()
-                .find(|w| matches!(w.target, Target::Item(i) if i == row))
-                .unwrap()
-        };
-        ui.scroll = find(&mut ui).y - GraphicsUi::bounds(480.0).0 - 4.0;
-        let w = find(&mut ui);
-        assert_eq!(
-            ui.click(
-                Level::Advanced,
-                &mut s,
-                (w.x + 1.0, w.y + 1.0),
-                (854.0, 480.0),
-                [854, 480],
-                false,
-                false
-            ),
-            [Action::ButtonClick, Action::OpenShaderPacks]
-        );
-        assert_eq!(s.horizon.shader_pack, "horizon-sample");
-    }
-
    #[test]
    fn presets_set_vanilla_and_horizon_options() {
        let mut s = Settings::default();
@@ -1058,48 +994,6 @@ mod tests {
        assert_eq!(s.horizon.upload_budget_kib, 0);
    }

-    #[test]
-    fn cull_leaves_is_opt_in_and_toggles_from_advanced_graphics() {
-        let mut s = Settings::default();
-        let item = Item::Horizon(H::CullLeaves);
-        assert_eq!(item.switch(&s), Some(false));
-        assert_eq!(item.label(&s).plain(), "Cull Leaves: Off");
-        for enabled in [false, true] {
-            s.horizon.cull_leaves = enabled;
-            for preset in Preset::ALL {
-                crate::graphics::apply_preset(preset, &mut s);
-                assert_eq!(s.horizon.cull_leaves, enabled);
-            }
-        }
-
-        let mut ui = GraphicsUi::default();
-        let size = (480.0, 4000.0);
-        let (widgets, _, _) = ui.layout(Level::Advanced, size.0, size.1);
-        let switch = widgets
-            .iter()
-            .find(|w| matches!(w.target, Target::Item(i) if i == item))
-            .unwrap();
-        let point = (switch.x + 1.0, switch.y + 1.0);
-        for enabled in [false, true] {
-            s.horizon.preset = Preset::Balanced;
-            assert_eq!(
-                ui.click(
-                    Level::Advanced,
-                    &mut s,
-                    point,
-                    size,
-                    [854, 480],
-                    false,
-                    false
-                ),
-                vec![Action::ButtonClick, Action::Changed]
-            );
-            assert_eq!(item.switch(&s), Some(enabled));
-            assert_eq!(s.horizon.preset, Preset::Custom);
-        }
-        assert_eq!(item.label(&s).plain(), "Cull Leaves: On");
-    }
-
    #[test]
    fn entity_culling_is_opt_in_and_toggles_from_advanced_graphics() {
        let mut s = Settings::default();
@@ -253,6 +253,22 @@ impl PlayerHealth {
            self.hurt_animation_time -= 1;
        }
    }
+    /// `LivingEntity.animateHurt` / `handleDamageEvent` on a client: the hurt
+    /// tilt and red flash restart.
+    pub fn animate_hurt(&mut self) {
+        self.hurt.hurt_duration = 10;
+        self.hurt.hurt_time = 10;
+        self.hurt_animation_time = 10;
+    }
+    /// `LocalPlayer.hurtTo` with `flashOnSetHealth`: a drop below the current
+    /// health starts the hurt animation.
+    pub fn flash_health_change(&mut self, health: f32) {
+        let damage = self.health() - health;
+        if damage > 0.0 {
+            self.hurt.last_hurt = damage;
+            self.animate_hurt();
+        }
+    }
 }
 impl PlayerMotion {
    pub fn hurt(
@@ -274,6 +290,9 @@ impl PlayerMotion {
        amount: f32,
        blocking: Option<Blocking>,
    ) -> Result<BlockOutcome> {
+        if self.client_side {
+            return Ok(BlockOutcome::default());
+        }
        let source = resources
            .damage
            .source::<()>(source, None, None, None)
@@ -298,6 +317,7 @@ impl PlayerMotion {
            blocking,
            blocked: 0.0,
            block_sound: false,
+            knocked: false,
            totem: totem_ready,
            totem_fired: false,
        };
@@ -313,6 +333,7 @@ impl PlayerMotion {
            hurt,
            blocked: environment.blocked,
            sound: environment.block_sound,
+            knockback: environment.knocked,
        };
        if environment.totem_fired {
            h.totem_used = true;
@@ -373,6 +394,8 @@ pub(crate) struct Environment<'a> {
    pub(crate) blocking: Option<Blocking>,
    pub(crate) blocked: f32,
    pub(crate) block_sound: bool,
+    /// `dealDefaultKnockback` ran: a fresh hit, not fully blocked.
+    pub(crate) knocked: bool,
    /// LivingEntity.checkTotemDeathProtection: a totem is held / was used.
    pub(crate) totem: bool,
    pub(crate) totem_fired: bool,
@@ -435,6 +458,9 @@ pub struct BlockOutcome {
    pub blocked: f32,
    /// `BlocksAttacks.onBlocked` ran (the block sound plays).
    pub sound: bool,
+    /// The hit knocks the player back (`dealDefaultKnockback`): not one in
+    /// the hurt cooldown, nor one the shield took whole.
+    pub knockback: bool,
 }
 struct MatchedSets;
 impl horizon_world::blocking_rules::TypeMatchWorld for MatchedSets {
@@ -667,9 +693,11 @@ impl HurtWorld for Environment<'_> {
        *self.sync_velocity = true;
        Ok(())
    }
+    /// The caller applies it: these sources carry no entity or position.
    fn knockback(&mut self, _: &mut State, _: f32, _: bool) -> io::Result<()> {
+        self.knocked = true;
        Ok(())
-    } // no entity or position on these sources
+    }
    fn death_protection(&mut self, _: &mut State) -> io::Result<bool> {
        if !self.totem
            || self
@@ -761,6 +789,37 @@ impl ServerPlayerHurtWorld for Environment<'_> {

 #[cfg(test)]
 mod tests {
+    #[test]
+    fn a_hit_in_the_hurt_cooldown_knocks_nobody_back() {
+        let root = std::path::Path::new(env!("CARGO_MANIFEST_DIR"))
+            .join("../../.local/horizon-client")
+            .join(horizon_core::VANILLA_VERSION);
+        if !root.join("movement-properties.nbt").exists() {
+            return;
+        }
+        let assets = crate::assets::Assets::load(&root).unwrap();
+        let resources = crate::motion::MotionResources::load(&root, &assets).unwrap();
+        let mut player =
+            crate::motion::PlayerMotion::new(&resources, horizon_core::geometry::Vec3::ZERO)
+                .unwrap();
+        let (health, rules) = (&resources.health, super::HealthRules::default());
+        let id = health.damage.id("minecraft:mob_attack").unwrap();
+        let mut hit = |amount| {
+            player
+                .hurt_blocking(health, rules, id, amount, None)
+                .unwrap()
+        };
+        let first = hit(1.0);
+        assert!(first.hurt && first.knockback);
+        // A stronger hit inside the cooldown hurts by the difference only
+        // (LivingEntity.hurtServer), with no dealDefaultKnockback.
+        let second = hit(2.0);
+        assert!(second.hurt && !second.knockback);
+        // A weaker one doesn't hurt at all.
+        let third = hit(1.5);
+        assert!(!third.hurt && !third.knockback);
+    }
+
    #[test]
    fn hurt_sounds_follow_damage_effects() {
        // DamageEffects: HURT, THORNS, DROWNING, BURNING, POKING, FREEZING.
@@ -81,6 +81,12 @@ pub const MINIMAP_SPRITE: &str = "horizon/minimap";
 pub const SKIN_SLOTS: usize = 32;
 /// Reused by the visible rows of the classic world selector.
 pub const WORLD_ICON_SLOTS: usize = 32;
+/// Atlas slots for the pack icons on the pack screen, one per icon drawn
+/// (`PackSelectionScreen.loadPackIcon` registers a texture per pack): two lists
+/// of 36-pixel rows at GUI scale 2 on a 4K screen still fit.
+pub const PACK_ICON_SLOTS: usize = 64;
+/// A pack icon slot's side: vanilla's own icons are 128x128.
+pub const PACK_ICON_SIZE: u32 = 128;
 /// Atlas slots for armour trim textures made at run time (`trims`), each the
 /// size of the largest trim texture.
 pub const TRIM_SLOTS: usize = 32;
@@ -252,7 +258,7 @@ impl HudAtlas {
        )
    }
    /// Empty slots written at run time: map textures (game/maps.rs), the
-    /// minimap, downloaded skins, world icons and the on-screen keyboard's text.
+    /// minimap, downloaded skins, world and pack icons and the on-screen keyboard's text.
    fn slots(images: &mut Vec<PackedImage>, trim: (u32, u32)) {
        for i in 0..MAP_SLOTS {
            images.push((format!("horizon/map{i}"), 128, 128, vec![0; 128 * 128 * 4]));
@@ -284,6 +290,15 @@ impl HudAtlas {
                vec![0; 64 * 64 * 4],
            ));
        }
+        let side = PACK_ICON_SIZE as usize;
+        for i in 0..PACK_ICON_SLOTS {
+            images.push((
+                format!("horizon/pack-icon{i}"),
+                PACK_ICON_SIZE,
+                PACK_ICON_SIZE,
+                vec![0; side * side * 4],
+            ));
+        }
        // The on-screen keyboard's text and corner masks (ui_theme), rasterized at run time.
        images.push((
            "horizon/ui-text".into(),
@@ -55,6 +55,9 @@ impl PlayerMotion {
        Ok(())
    }
    pub fn food_tick(&mut self, resources: &HealthResources, rules: HealthRules) -> Result<()> {
+        if self.client_side {
+            return Ok(());
+        }
        let h = &mut self.health;
        let mut world = TickWorld {
            resources,
@@ -156,6 +159,7 @@ impl FoodWorld for TickWorld<'_> {
            blocking: None,
            blocked: 0.0,
            block_sound: false,
+            knocked: false,
            totem: false,
            totem_fired: false,
        };
@@ -271,23 +271,15 @@ fn read_levels(t: Option<&Tag>) -> Levels {
        return Vec::new();
    };
    // Pre-1.21.5 worlds wrap the map in {levels: {...}}.
-    if let Some(Tag::Compound(inner)) = map.get(&JavaString::from("levels")) {
-        return inner
-            .iter()
-            .filter_map(|(k, v)| {
-                Some((
-                    Arc::from(k.to_string_lossy().as_str()),
-                    int(v)?.clamp(1, 255) as u32,
-                ))
-            })
-            .collect();
-    }
+    let map = match map.get(&JavaString::from("levels")) {
+        Some(Tag::Compound(inner)) => inner,
+        _ => map,
+    };
+    // The keys are enchantment Identifiers: `knockback` is `minecraft:knockback`.
    map.iter()
        .filter_map(|(k, v)| {
-            Some((
-                Arc::from(k.to_string_lossy().as_str()),
-                int(v)?.clamp(1, 255) as u32,
-            ))
+            let id = horizon_world::datafix::dynamic::namespaced(&k.to_string_lossy());
+            Some((Arc::from(id), int(v)?.clamp(1, 255) as u32))
        })
        .collect()
 }
@@ -863,6 +855,22 @@ mod tests {
        assert_eq!(back.custom_name(), Some("Blade"));
    }

+    #[test]
+    fn enchantment_ids_without_a_namespace_are_minecraft_ones() {
+        let levels = Tag::compound([
+            ("knockback", Tag::Int(2)),
+            ("minecraft:sharpness", Tag::Int(1)),
+        ]);
+        let components = Tag::compound([("minecraft:enchantments", levels)]);
+        let (_, extra) = decode_components(Some(&components));
+        let stack = ItemStack {
+            extra,
+            ..ItemStack::new("minecraft:wooden_sword", 1)
+        };
+        assert_eq!(stack.enchantment_level("minecraft:knockback"), 2);
+        assert_eq!(stack.enchantment_level("minecraft:sharpness"), 1);
+    }
+
    #[test]
    fn custom_name_reads_the_extra_spans() {
        let name = Tag::compound([
@@ -1051,7 +1051,7 @@ impl LootContext<'_> {
                continue;
            }
            // LootPool: rolls.getInt (Mth.randomBetweenInclusive for uniform rolls).
-            let rolls = ctx.int_number(&pool["rolls"], random).max(0) as u32;
+            let rolls = LootContext::int_number(&pool["rolls"], random).max(0) as u32;
            for _ in 0..rolls {
                let mut produced = Vec::new();
                ctx.choose(
@@ -1085,7 +1085,7 @@ impl LootContext<'_> {
    fn enchantment_level(&self, id: &str) -> u32 {
        self.held.map_or(0, |h| h.enchantment_level(id))
    }
-    fn number<R: RandomSource>(&self, v: &Value, random: &mut R) -> f32 {
+    fn number<R: RandomSource>(v: &Value, random: &mut R) -> f32 {
        match v {
            Value::Number(n) => n.as_f64().unwrap_or(0.0) as f32,
            Value::Object(o) => match o
@@ -1097,8 +1097,8 @@ impl LootContext<'_> {
                    o.get("value").and_then(Value::as_f64).unwrap_or(0.0) as f32
                }
                "minecraft:uniform" => {
-                    let min = self.number(o.get("min").unwrap_or(&Value::Null), random);
-                    let max = self.number(o.get("max").unwrap_or(&Value::Null), random);
+                    let min = Self::number(o.get("min").unwrap_or(&Value::Null), random);
+                    let max = Self::number(o.get("max").unwrap_or(&Value::Null), random);
                    // UniformGenerator.getFloat / getInt (Mth.nextInt) differ; use int for counts.
                    if max <= min {
                        min
@@ -1107,8 +1107,8 @@ impl LootContext<'_> {
                    }
                }
                "minecraft:binomial" => {
-                    let n = self.number(o.get("n").unwrap_or(&Value::Null), random) as u32;
-                    let p = self.number(o.get("p").unwrap_or(&Value::Null), random);
+                    let n = Self::number(o.get("n").unwrap_or(&Value::Null), random) as u32;
+                    let p = Self::number(o.get("p").unwrap_or(&Value::Null), random);
                    (0..n).filter(|_| random.next_float() < p).count() as f32
                }
                _ => 1.0,
@@ -1116,22 +1116,22 @@ impl LootContext<'_> {
            _ => 1.0,
        }
    }
-    fn int_number<R: RandomSource>(&self, v: &Value, random: &mut R) -> i32 {
+    fn int_number<R: RandomSource>(v: &Value, random: &mut R) -> i32 {
        if let Value::Object(o) = v
            && o.get("type")
                .and_then(Value::as_str)
                .unwrap_or("minecraft:uniform")
                == "minecraft:uniform"
        {
-            let min = self.int_number(o.get("min").unwrap_or(&Value::Null), random);
-            let max = self.int_number(o.get("max").unwrap_or(&Value::Null), random);
+            let min = Self::int_number(o.get("min").unwrap_or(&Value::Null), random);
+            let max = Self::int_number(o.get("max").unwrap_or(&Value::Null), random);
            return if max <= min {
                min
            } else {
                min + random.next_int_bound(max - min + 1).unwrap_or(0)
            };
        }
-        self.number(v, random).round() as i32
+        Self::number(v, random).round() as i32
    }
    fn condition<R: RandomSource>(&self, c: &Value, random: &mut R) -> bool {
        let (kind, c) = match c {
@@ -1157,7 +1157,7 @@ impl LootContext<'_> {
                .into_iter()
                .flatten()
                .all(|t| self.condition(t, random)),
-            "minecraft:random_chance" => random.next_float() < self.number(&c["chance"], random),
+            "minecraft:random_chance" => random.next_float() < Self::number(&c["chance"], random),
            "minecraft:table_bonus" => {
                // BonusLevelTableCondition: chances[min(level, len - 1)].
                let level =
@@ -1378,7 +1378,7 @@ impl LootContext<'_> {
            }
            match f["type"].as_str().or(f["function"].as_str()).unwrap_or("") {
                "minecraft:set_count" => {
-                    let n = self.int_number(&f["count"], random);
+                    let n = Self::int_number(&f["count"], random);
                    let base = if f["add"].as_bool() == Some(true) {
                        stack.count as i32
                    } else {
@@ -1421,7 +1421,7 @@ impl LootContext<'_> {
                    // Attacker's level x count, rounded (looting).
                    let level = self.enchantment_level(f["enchantment"].as_str().unwrap_or(""));
                    if level > 0 && self.killed_by_player && self.block.is_empty() {
-                        let add = level as f32 * self.number(&f["count"], random);
+                        let add = level as f32 * Self::number(&f["count"], random);
                        stack.count = (stack.count as i32 + add.round() as i32).max(0) as u32;
                        if let Some(limit) = f["limit"].as_i64().filter(|l| *l > 0) {
                            stack.count = stack.count.min(limit as u32);
@@ -1,299 +0,0 @@
-//! Java (OptiFine/Iris) shader packs in `shaderpacks/` (docs/shader-packs.md):
-//! a folder holding `shaders/`, or a `.zip`. `horizon-shaderpack` translates
-//! their full-screen programs (`begin`, `prepare`, `deferred`, `composite`,
-//! `final`) to WGSL, and `gfx/java_stages.rs` runs them over Horizon's world
-//! as Iris runs them over its own. Geometry programs (`gbuffers_*`,
-//! `shadow`) don't run yet: the world is drawn by Horizon.
-use horizon_shaderpack::{
-    JavaPack,
-    pipeline::{Directives, Program, TargetSettings},
-    preprocess::Environment,
-    properties::SkyDirectives,
-    uniforms::CustomUniforms,
-};
-use std::{
-    collections::{BTreeMap, BTreeSet},
-    path::Path,
-};
-
-/// The passes of one program folder (`world0`, or `""` for the pack's root).
-pub struct JavaFolder {
-    pub folder: String,
-    pub targets: Vec<TargetSettings>,
-    /// `begin*`, `prepare*`, `deferred*`, `composite*`, in order.
-    pub passes: Vec<Program>,
-    /// How many of `passes` run before the world (`begin*`, `prepare*`): the
-    /// world's colour and depth enter `world_target` and `depthtex*` after them.
-    pub world_at: usize,
-    /// The colour target the world goes into, where the pack's terrain
-    /// program draws (MakeUp: colortex1).
-    pub world_target: u32,
-    /// The targets whose alternate side the world is written to.
-    pub flipped_after_prepare: BTreeSet<u32>,
-    pub final_pass: Option<Program>,
-    /// The targets whose alternate side holds the frame's last write.
-    pub flipped_at_end: BTreeSet<u32>,
-    /// `sunPathRotation`, `eyeBrightnessHalflife`, `wetnessHalflife` and
-    /// `drynessHalflife`.
-    pub directives: Directives,
-}
-
-/// The key of `texture.noise` (`noisetex`) in [`JavaPasses::custom_textures`].
-pub const NOISE_KEY: &str = "noise";
-
-/// The key of `texture.<stage>.<sampler>` in [`JavaPasses::custom_textures`]
-/// for a pass of `program` (`world0/composite2`): Iris's texture stages, where
-/// `final` reads the `composite` ones.
-pub fn texture_key(program: &str, sampler: &str) -> String {
-    let name = program.rsplit('/').next().unwrap_or(program);
-    let stage = match name.trim_end_matches(|c: char| c.is_ascii_digit()) {
-        "final" => "composite",
-        stage => stage,
-    };
-    format!("{stage}.{sampler}")
-}
-
-/// A loaded Java pack.
-pub struct JavaPasses {
-    pub folders: Vec<JavaFolder>,
-    /// `uniform.*` / `variable.*` from `shaders.properties`.
-    pub uniforms: CustomUniforms,
-    /// What the pack keeps of the vanilla sky (`clouds`, `sun`, `moon`).
-    pub sky: SkyDirectives,
-    /// `texture.<stage>.<sampler>` and `texture.noise` images, by
-    /// `"<stage>.<sampler>"` and [`NOISE_KEY`].
-    pub custom_textures: BTreeMap<String, crate::shader_pack::Rgba>,
-}
-
-impl JavaPasses {
-    /// The folder Iris uses in `dimension` (0 overworld, -1 the Nether, 1 the
-    /// End): `world<N>` when the pack has one, else `world0`, else the root.
-    pub fn folder_for(&self, dimension: i8) -> Option<usize> {
-        let find = |name: &str| self.folders.iter().position(|f| f.folder == name);
-        find(&format!("world{dimension}"))
-            .or_else(|| find("world0"))
-            .or_else(|| find(""))
-    }
-}
-
-/// A folder holding `shaders/`, or a zip.
-pub fn is_java_pack(path: &Path) -> bool {
-    path.join("shaders").is_dir()
-        || path.is_file()
-            && path
-                .extension()
-                .is_some_and(|e| e.eq_ignore_ascii_case("zip"))
-}
-
-/// The `MC_GL_VENDOR_*` name of a wgpu adapter (`AdapterInfo::vendor`, a
-/// PCI id; Apple's GPUs report 0).
-pub fn vendor_name(vendor: u32, adapter: &str) -> &'static str {
-    match vendor {
-        0x10de => "NVIDIA Corporation",
-        0x1002 | 0x1022 => "AMD",
-        0x8086 => "Intel",
-        _ if adapter.starts_with("Apple") => "Apple",
-        _ => "Unknown",
-    }
-}
-
-/// Open the pack at `path` and translate its full-screen passes with the
-/// player's `values`; `vendor` and `renderer` name the GPU to the pack.
-pub fn load(
-    path: &Path,
-    values: &BTreeMap<String, String>,
-    vendor: &str,
-    renderer: &str,
-) -> Result<JavaPasses, String> {
-    let pack = JavaPack::open(path)?;
-    let values = pack.values(values);
-    let env = Environment::iris(vendor, renderer, 4);
-    let properties = pack.properties(&values, &env)?;
-    let mut names: Vec<&str> = ["world0", "world-1", "world1"]
-        .into_iter()
-        .filter(|d| {
-            pack.programs
-                .iter()
-                .any(|p| p.starts_with(&format!("{d}/")))
-        })
-        .collect();
-    if pack.programs.iter().any(|p| !p.contains('/')) {
-        names.push("");
-    }
-    let mut folders = Vec::new();
-    for name in names {
-        let plan = pack.passes(name, &values, &env, &properties)?;
-        let compile = |pass| {
-            let program = pack.compile(pass, &plan.targets, &values, &env, &properties)?;
-            if let Some((image, _)) = program.fragment.interface.images.first() {
-                return Err(format!(
-                    "{}: images ({image}) aren't supported yet",
-                    program.pass.program
-                ));
-            }
-            Ok::<_, String>(program)
-        };
-        let early = plan.begin.iter().chain(&plan.prepare);
-        let passes = early
-            .clone()
-            .chain(&plan.deferred)
-            .chain(&plan.composite)
-            .map(compile)
-            .collect::<Result<Vec<_>, _>>()?;
-        let final_pass = plan.final_pass.as_ref().map(compile).transpose()?;
-        if passes.is_empty() && final_pass.is_none() {
-            continue;
-        }
-        folders.push(JavaFolder {
-            folder: name.to_owned(),
-            targets: plan.targets,
-            world_at: early.count(),
-            world_target: plan.world_target,
-            passes,
-            flipped_after_prepare: plan.flipped_after_prepare,
-            final_pass,
-            flipped_at_end: plan.flipped_at_end,
-            directives: plan.directives,
-        });
-    }
-    if folders.is_empty() {
-        return Err("no deferred, composite or final programs".into());
-    }
-    let mut custom_textures = BTreeMap::new();
-    for tex in properties.custom_textures() {
-        let key = match tex.stage {
-            Some(stage) => format!("{stage}.{}", tex.sampler),
-            None if tex.sampler == NOISE_KEY => NOISE_KEY.to_owned(),
-            None => continue,
-        };
-        // Only PNGs for now: resource locations and raw `.dat` textures are
-        // skipped and the sampler reads what it would without them.
-        let image = pack
-            .files
-            .read_bytes(&tex.path)
-            .ok_or_else(|| "not in the pack".to_owned())
-            .and_then(|bytes| crate::shader_pack::decode_png(&bytes));
-        match image {
-            Ok(image) => {
-                custom_textures.insert(key, image);
-            }
-            Err(e) => log::warn!("Horizon: shader pack texture {}: {e}", tex.path),
-        }
-    }
-    let uniforms = properties.custom_uniforms();
-    for problem in &uniforms.problems {
-        log::warn!("Horizon: shader pack custom uniform {problem}");
-    }
-    Ok(JavaPasses {
-        folders,
-        uniforms,
-        sky: properties.sky(),
-        custom_textures,
-    })
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn custom_textures_belong_to_iris_s_stages() {
-        assert_eq!(texture_key("world0/composite2", "gaux1"), "composite.gaux1");
-        assert_eq!(texture_key("final", "colortex4"), "composite.colortex4");
-        assert_eq!(
-            texture_key("world-1/deferred10", "noisetex"),
-            "deferred.noisetex"
-        );
-        assert_eq!(texture_key("prepare", "depthtex2"), "prepare.depthtex2");
-    }
-
-    #[test]
-    fn loads_the_full_screen_passes_of_a_java_pack() {
-        let dir = Path::new(env!("CARGO_MANIFEST_DIR"))
-            .join("../horizon-shaderpack/tests/fixtures/passes");
-        assert!(is_java_pack(&dir));
-        let pack = load(&dir, &BTreeMap::new(), "Apple", "Apple M4 Pro").unwrap();
-        let [folder] = &pack.folders[..] else {
-            panic!("one folder, the root");
-        };
-        assert_eq!(folder.folder, "");
-        assert_eq!(
-            folder
-                .passes
-                .iter()
-                .map(|p| p.pass.program.as_str())
-                .collect::<Vec<_>>(),
-            ["deferred", "composite", "composite1"]
-        );
-        assert_eq!(folder.world_at, 0);
-        assert!(folder.final_pass.is_some());
-        // The overworld, the Nether and the End all use the root.
-        assert_eq!([-1, 0, 1].map(|d| pack.folder_for(d)), [Some(0); 3]);
-        assert_eq!(
-            vendor_name(0x10de, "NVIDIA GeForce RTX 4080"),
-            "NVIDIA Corporation"
-        );
-        assert_eq!(vendor_name(0, "Apple M4 Pro"), "Apple");
-    }
-
-    /// wgpu is given the WGSL text: it must parse again.
-    fn reparse_error(pack: &JavaPasses) -> Option<String> {
-        let passes = pack
-            .folders
-            .iter()
-            .flat_map(|f| f.passes.iter().chain(&f.final_pass));
-        passes
-            .flat_map(|p| [(p, &p.vertex, "vsh"), (p, &p.fragment, "fsh")])
-            .find_map(|(p, t, ext)| {
-                let e = naga::front::wgsl::parse_str(&t.wgsl).err()?;
-                Some(format!(
-                    "{}.{ext}: {}",
-                    p.pass.program,
-                    e.emit_to_string(&t.wgsl)
-                ))
-            })
-    }
-
-    /// The packs in `HORIZON_TEST_SHADERPACKS` (folders or zips) load as the
-    /// game loads them, with their default options: the compatibility table
-    /// of docs/shader-packs.md. Skipped when the variable isn't set.
-    #[test]
-    fn real_packs_load() {
-        let Some(dir) = std::env::var_os("HORIZON_TEST_SHADERPACKS") else {
-            return;
-        };
-        let mut entries: Vec<_> = std::fs::read_dir(dir)
-            .unwrap()
-            .flatten()
-            .map(|e| e.path())
-            .filter(|p| is_java_pack(p))
-            .collect();
-        entries.sort();
-        let mut failures = Vec::new();
-        for path in entries {
-            let name = path.file_name().unwrap().to_string_lossy().into_owned();
-            match load(&path, &BTreeMap::new(), "Apple", "Apple M4 Pro") {
-                Ok(pack) if let Some(e) = reparse_error(&pack) => {
-                    println!("{name}: {e}");
-                    failures.push(name);
-                }
-                Ok(pack) => {
-                    let folders: Vec<String> = pack
-                        .folders
-                        .iter()
-                        .map(|f| {
-                            let n = f.passes.len() + usize::from(f.final_pass.is_some());
-                            format!("{} {n} passes", f.folder)
-                        })
-                        .collect();
-                    println!("{name}: loads ({})", folders.join(", "));
-                }
-                Err(e) => {
-                    println!("{name}: {e}");
-                    failures.push(name);
-                }
-            }
-        }
-        assert!(failures.is_empty(), "{failures:?}");
-    }
-}
@@ -119,6 +119,88 @@ fn component_value(tag: &horizon_world::nbt::Tag) -> crate::server::json::Json {
    }
 }

+/// The inverse of [`component_value`]: a JSON component (a server.properties
+/// prompt) as ComponentSerialization.CODEC writes it with NbtOps. An array is
+/// its first component with the rest appended (`createFromList`); a list of
+/// components mixing plain strings and objects has the strings as `{text}`.
+pub fn component_tag(v: &crate::server::json::Json) -> horizon_world::nbt::Tag {
+    use crate::server::json::Json;
+    use horizon_world::nbt::{JavaString, Tag};
+    fn list(items: &[Json]) -> Tag {
+        same_kind(items.iter().map(component_tag).collect())
+    }
+    fn same_kind(mut tags: Vec<Tag>) -> Tag {
+        if tags.iter().any(|t| matches!(t, Tag::Compound(_))) {
+            for t in &mut tags {
+                if let Tag::String(s) = t {
+                    *t = Tag::compound([("text", Tag::String(s.clone()))]);
+                }
+            }
+        }
+        Tag::List(tags)
+    }
+    fn value(v: &Json) -> Tag {
+        match v {
+            Json::Bool(b) => Tag::Byte(i8::from(*b)),
+            Json::Number(n) => n.parse().map_or_else(
+                |_| Tag::Double(n.parse::<f64>().unwrap_or(0.0).to_bits()),
+                Tag::Int,
+            ),
+            Json::String(s) => Tag::String(JavaString::from(s.as_str())),
+            Json::Array(items) => list(items),
+            Json::Object(members) => Tag::compound(
+                members
+                    .iter()
+                    .map(|(k, v)| (k.as_str(), value(v)))
+                    .collect::<Vec<_>>(),
+            ),
+            Json::Null => Tag::String(JavaString::from("")),
+        }
+    }
+    match v {
+        Json::Array(items) if !items.is_empty() => {
+            let mut first = component_tag(&items[0]);
+            if let Tag::String(s) = &first {
+                first = Tag::compound([("text", Tag::String(s.clone()))]);
+            }
+            if let Tag::Compound(map) = &mut first {
+                let mut extra = match map.remove(&JavaString::from("extra")) {
+                    Some(Tag::List(e)) => e,
+                    _ => Vec::new(),
+                };
+                extra.extend(items[1..].iter().map(component_tag));
+                map.insert(JavaString::from("extra"), same_kind(extra));
+            }
+            first
+        }
+        Json::Object(members) => {
+            if let [(key, Json::String(text))] = members.as_slice()
+                && key == "text"
+            {
+                return Tag::String(JavaString::from(text.as_str()));
+            }
+            Tag::compound(
+                members
+                    .iter()
+                    .map(|(k, v)| {
+                        let tag = match k.as_str() {
+                            "extra" | "with" => match v {
+                                Json::Array(items) => list(items),
+                                other => value(other),
+                            },
+                            _ => value(v),
+                        };
+                        (k.as_str(), tag)
+                    })
+                    .collect::<Vec<_>>(),
+            )
+        }
+        Json::String(s) | Json::Number(s) => Tag::String(JavaString::from(s.as_str())),
+        Json::Bool(b) => Tag::String(JavaString::from(b.to_string().as_str())),
+        _ => Tag::String(JavaString::from("")),
+    }
+}
+
 /// StringUtil.isValidPlayerName.
 pub fn valid_name(name: &str) -> bool {
    (1..=16).contains(&name.len()) && name.chars().all(|c| c as u32 > 32 && (c as u32) < 127)
@@ -745,6 +827,14 @@ fn login_and_configure(
        send(c, cfg::Clientbound::RegistryData(packet))?;
    }
    send(c, cfg::Clientbound::UpdateTags(sync.tags.clone()))?;
+    if let Some(pack) = &shared.config.resource_pack
+        && let Some(rejected) = offer_pack(c, pack, &mut info)?
+    {
+        let (reason, text) = pack_rejected(shared, name, rejected);
+        let _ = send(c, cfg::Clientbound::Disconnect(cfg::Disconnect { reason }));
+        lost(shared, &format!("{name} ({})", uuid_string(uuid)), &text);
+        return Ok(None);
+    }
    send(c, cfg::Clientbound::FinishConfiguration(Empty))?;
    loop {
        let (id, payload) = c.recv().map_err(e)?;
@@ -763,6 +853,79 @@ fn login_and_configure(
    }))
 }

+/// ServerboundResourcePackPacket.Action.DECLINED.
+const PACK_DECLINED: i32 = 1;
+
+/// ServerCommonPacketListenerImpl.handleResourcePackResponse: a player who
+/// declined the required pack is disconnected. The reason and its text.
+fn pack_rejected(shared: &Shared, name: &str, pack: u128) -> (horizon_world::nbt::Tag, String) {
+    let reason = translatable("multiplayer.requiredTexturePrompt.disconnect", &[]);
+    let Some(log) = &shared.config.log else {
+        return (reason, String::new());
+    };
+    let line = format!(
+        "Disconnecting {name} due to resource pack {} rejection",
+        uuid_string(pack)
+    );
+    (log.write)("Server thread", "INFO", &line);
+    let text = horizon_protocol::text::plain(&reason, &log.lang);
+    (reason, text)
+}
+
+/// ServerResourcePackConfigurationTask: offer the server's pack, then wait
+/// for the client's final answer (`Action.isTerminal`: anything but
+/// ACCEPTED or DOWNLOADED). The player may take a while to answer the
+/// prompt, so the connection is kept alive meanwhile, as
+/// ServerConfigurationPacketListenerImpl.tick does. The id of a required
+/// pack the client declined, which disconnects it.
+fn offer_pack(
+    c: &mut Connection,
+    pack: &crate::server::properties::ResourcePackInfo,
+    info: &mut ClientInformation,
+) -> Result<Option<u128>, String> {
+    let e = |e: horizon_protocol::Error| e.to_string();
+    let push = cfg::ResourcePackPush {
+        id: pack.id,
+        url: pack.url.clone(),
+        hash: pack.hash.clone(),
+        required: pack.required,
+        prompt: pack.prompt.as_ref().map(component_tag),
+    };
+    c.send(&cfg::Clientbound::ResourcePackPush(push).encode())
+        .map_err(e)?;
+    std::thread::scope(|scope| {
+        let (stop, stopped) = channel::<()>();
+        let writer = &mut c.writer;
+        scope.spawn(move || {
+            let start = Instant::now();
+            while stopped.recv_timeout(KEEP_ALIVE_EVERY) == Err(RecvTimeoutError::Timeout) {
+                let id = i64::try_from(start.elapsed().as_millis()).unwrap_or(0);
+                let keep_alive = cfg::Clientbound::KeepAlive(cfg::KeepAlive { id });
+                if writer.send(&keep_alive.encode()).is_err() {
+                    break;
+                }
+            }
+        });
+        let answer = loop {
+            let (id, payload) = match c.reader.recv() {
+                Ok(packet) => packet,
+                Err(err) => break Err(err.to_string()),
+            };
+            match cfg::Serverbound::decode(id, &payload) {
+                Ok(cfg::Serverbound::ResourcePack(r)) if !matches!(r.action, 3 | 4) => {
+                    let rejected = r.action == PACK_DECLINED && pack.required;
+                    break Ok(rejected.then_some(r.id));
+                }
+                Ok(cfg::Serverbound::ClientInformation(i)) => *info = i,
+                Ok(_) => {}
+                Err(err) => break Err(err.to_string()),
+            }
+        };
+        drop(stop);
+        answer
+    })
+}
+
 fn play(c: Connection, shared: &Arc<Shared>, parts: Parts, address: std::net::SocketAddr) {
    let conn_id = shared.next_id();
    let events = shared.events.clone();
@@ -784,6 +947,7 @@ fn play(c: Connection, shared: &Arc<Shared>, parts: Parts, address: std::net::So
            })
            .ok()
    };
+    let name = parts.name.clone();
    let joined = Joined {
        conn: conn_id,
        uuid: parts.uuid,
@@ -795,8 +959,20 @@ fn play(c: Connection, shared: &Arc<Shared>, parts: Parts, address: std::net::So
        latency,
        address,
    };
+    let required_pack = shared
+        .config
+        .resource_pack
+        .as_ref()
+        .is_some_and(|p| p.required);
    let reason = if events.send(NetEvent::Joined(Box::new(joined))).is_ok() {
-        read_loop(&mut reader, conn_id, &events, &alive)
+        match read_loop(&mut reader, conn_id, &events, &alive, required_pack) {
+            Ok(reason) => reason,
+            Err(rejected) => {
+                let (reason, text) = pack_rejected(shared, &name, rejected);
+                let _ = tx.send(Out::Disconnect(reason));
+                text
+            }
+        }
    } else {
        "server closed".to_owned()
    };
@@ -808,12 +984,16 @@ fn play(c: Connection, shared: &Arc<Shared>, parts: Parts, address: std::net::So
    shared.release(parts.uuid);
 }

+/// Forward the player's packets until the connection ends: why it did, or
+/// the id of a required resource pack the player declined (with
+/// `required_pack`), which disconnects them.
 fn read_loop(
    reader: &mut ConnReader,
    conn: u32,
    events: &Sender<NetEvent>,
    alive: &AtomicI64,
-) -> String {
+    required_pack: bool,
+) -> Result<String, u128> {
    loop {
        let (id, payload) = match reader.recv() {
            Ok(p) => p,
@@ -824,19 +1004,24 @@ fn read_loop(
                    || e.0.contains("reset by peer")
                    || e.0.contains("aborted") =>
            {
-                return "Disconnected".to_owned();
+                return Ok("Disconnected".to_owned());
            }
-            Err(e) => return e.to_string(),
+            Err(e) => return Ok(e.to_string()),
        };
        match play::Serverbound::decode(id, &payload) {
            Ok(play::Serverbound::KeepAlive(k)) => alive.store(k.id, Ordering::Relaxed),
+            Ok(play::Serverbound::ResourcePack(r))
+                if r.action == PACK_DECLINED && required_pack =>
+            {
+                return Err(r.id);
+            }
            Ok(p) => {
                if events.send(NetEvent::Packet(conn, Box::new(p))).is_err() {
-                    return "server closed".to_owned();
+                    return Ok("server closed".to_owned());
                }
            }
            // A malformed packet disconnects like vanilla's decoder exception.
-            Err(e) => return format!("Invalid packet {id}: {e}"),
+            Err(e) => return Ok(format!("Invalid packet {id}: {e}")),
        }
    }
 }
@@ -988,6 +1173,24 @@ fn write_loop(
 mod tests {
    use super::*;

+    #[test]
+    fn prompts_become_the_components_vanilla_sends() {
+        let tag = |json: &str| {
+            let tag = component_tag(&crate::server::json::parse(json, true).unwrap());
+            component_json(&tag)
+        };
+        assert_eq!(tag(r#"{"text":"Hi"}"#), r#""Hi""#);
+        assert_eq!(tag(r#""Hi""#), r#""Hi""#);
+        assert_eq!(
+            tag(r#"["Hi ",{"text":"there","bold":true}]"#),
+            r#"{"text":"Hi ","extra":[{"text":"there","bold":true}]}"#
+        );
+        assert_eq!(
+            tag(r#"{"translate":"a","with":["b",{"text":"c","color":"red"}]}"#),
+            r#"{"translate":"a","with":["b",{"text":"c","color":"red"}]}"#
+        );
+    }
+
    fn unpack(out: Out) -> Vec<Vec<u8>> {
        match out {
            Out::Packet(body) => vec![body],
@@ -206,6 +206,9 @@ pub struct Guest {
    /// (Entity.DATA_AIR_SUPPLY_ID, Player.DATA_PLAYER_ABSORPTION_ID); their
    /// defaults until either changes.
    pub sent_air: (i32, f32),
+    /// The shared flags (Entity.DATA_SHARED_FLAGS_ID) the player's client was
+    /// last sent about itself.
+    pub sent_shared: i8,
    /// Where the player last died (Player.lastDeathLocation), sent with the respawn.
    pub last_death: Option<[i32; 3]>,
    /// The last action sequence to acknowledge at the next tick (-1: none).
@@ -336,6 +339,7 @@ impl Guest {
            sent_health: None,
            sent_xp: None,
            sent_air: (300, 0.0),
+            sent_shared: 0,
            last_death: None,
            ack_up_to: std::cell::Cell::new(-1),
            sent_selected: 0,
@@ -432,6 +436,13 @@ pub fn stack_to_network(
    item_id: impl Fn(&str) -> i32,
    enchantment_id: impl Fn(&str) -> Option<i32>,
    s: &Option<ItemStack>,
+) -> Option<Stack> {
+    network_stack(&item_id, &enchantment_id, s)
+}
+fn network_stack(
+    item_id: &dyn Fn(&str) -> i32,
+    enchantment_id: &dyn Fn(&str) -> Option<i32>,
+    s: &Option<ItemStack>,
 ) -> Option<Stack> {
    let s = s.as_ref()?;
    let mut stack = Stack::new(item_id(&s.item), s.count as i32);
@@ -488,6 +499,18 @@ pub fn stack_to_network(
                horizon_protocol::item::Component::Int(i32::from(mode)),
            ));
        }
+        // A loaded crossbow's ammunition.
+        if !d.charged.is_empty() {
+            let charged = d
+                .charged
+                .iter()
+                .filter_map(|c| network_stack(item_id, enchantment_id, &Some(c.clone())))
+                .collect();
+            stack.added.push((
+                horizon_protocol::item::component::CHARGED_PROJECTILES,
+                horizon_protocol::item::Component::Stacks(charged),
+            ));
+        }
        // The books a lectern shows and a guest reads.
        if !d.writable_pages.is_empty() {
            stack.added.push((
@@ -1477,16 +1477,7 @@ impl Hub {
        attributes: Vec<play::AttributeSnapshot>,
    ) -> EntityState {
        let (sneaking, sprinting, gliding, sleeping) = flags;
-        let mut shared = 0i8;
-        if sneaking {
-            shared |= 0x02;
-        }
-        if sprinting {
-            shared |= 0x08;
-        }
-        if gliding {
-            shared |= -128;
-        }
+        let shared = shared_flags(sneaking, sprinting, gliding);
        let pose = if sleeping {
            2
        } else if gliding {
@@ -1764,6 +1755,18 @@ impl Hub {
                }));
            }
        }
+        // ServerEntity.sendDirtyEntityData: the shared flags go to the player
+        // too, so the sprint a hit stops (Player.causeExtraKnockback) stops
+        // on its client.
+        let g = &mut self.guests[i];
+        let shared = shared_flags(g.sneaking, g.sprinting, g.fall_flying);
+        if shared != g.sent_shared {
+            g.sent_shared = shared;
+            g.send(&C::SetEntityData(play::SetEntityData {
+                id: g.entity_id,
+                values: vec![(0, serializer::BYTE, Value::Byte(shared))],
+            }));
+        }
        // Sent when the health or the food level changes, or the saturation
        // reaches or leaves zero; a dead player's health of 0 too.
        let g = &mut self.guests[i];
@@ -1981,14 +1984,15 @@ impl Hub {
                    self.guests[i].sneaking = p.flags & 32 != 0;
                    self.guests[i].sprinting = p.flags & 64 != 0 && p.flags & 1 != 0;
                }
-                // OPEN_INVENTORY is the game's: the ridden mount's inventory.
-                S::PlayerCommand(p) if p.action == 5 => {
+                // OPEN_INVENTORY (the ridden mount's inventory) and
+                // START_FALL_FLYING (checked against the guest's chest slot
+                // and effects) are the game's.
+                S::PlayerCommand(p) if matches!(p.action, 5 | 6) => {
                    events.push(HostEvent::Packet(conn, Box::new(S::PlayerCommand(p))));
                }
                S::PlayerCommand(p) => match p.action {
                    1 => self.guests[i].sprinting = true,
                    2 => self.guests[i].sprinting = false,
-                    6 => self.guests[i].fall_flying = true,
                    // STOP_SLEEPING.
                    0 => self.wake(i),
                    _ => {}
@@ -2479,6 +2483,7 @@ impl Hub {
        g.sent_health = None;
        g.sent_xp = None;
        g.sent_air = (300, 0.0);
+        g.sent_shared = 0;
        let (cx, cz) = g.chunk();
        g.send(&C::SetChunkCacheCenter(play::SetChunkCacheCenter {
            x: cx,
@@ -2518,6 +2523,21 @@ fn ticking_state(rate: f32, frozen: bool) -> C {
    raw(ids::TICKING_STATE, w.data)
 }

+/// Entity.DATA_SHARED_FLAGS_ID of a player: crouching, sprinting, gliding.
+fn shared_flags(sneaking: bool, sprinting: bool, gliding: bool) -> i8 {
+    let mut shared = 0i8;
+    if sneaking {
+        shared |= 0x02;
+    }
+    if sprinting {
+        shared |= 0x08;
+    }
+    if gliding {
+        shared |= -128;
+    }
+    shared
+}
+
 #[cfg(test)]
 mod tests {
    use super::*;
@@ -139,6 +139,9 @@ pub struct NetConfig {
    /// Online mode: players are authenticated (none on a LAN world).
    pub online: Option<Arc<OnlineMode>>,
    pub log: Option<NetLog>,
+    /// server.properties `resource-pack`: offered to every player during
+    /// configuration (a dedicated server's; MinecraftServer.getServerResourcePack).
+    pub resource_pack: Option<crate::server::properties::ResourcePackInfo>,
 }
 impl NetConfig {
    /// MinecraftServer.enforceSecureProfile.
@@ -164,6 +167,7 @@ impl NetConfig {
            gate: None,
            online: None,
            log: None,
+            resource_pack: None,
        }
    }
 }
@@ -41,6 +41,7 @@ pub mod command;
 pub mod command_block;
 pub mod command_storage;
 pub mod component;
+pub mod confirm_screen;
 pub mod container_screen;
 pub mod containers;
 pub mod control;
@@ -95,7 +96,6 @@ pub mod item_data;
 pub mod item_render;
 pub mod item_tooltip;
 pub mod items;
-pub mod java_pack;
 pub mod java_text;
 pub mod key_names;
 pub mod keybinds;
@@ -158,8 +158,8 @@ pub mod screen_effects;
 pub mod screen_layout;
 pub mod sculk;
 pub use horizon_server_files as server;
+pub mod server_packs;
 pub mod settings;
-pub mod shader_pack;
 pub mod shadows;
 pub mod signs;
 pub mod skins;
@@ -230,8 +230,6 @@ fn visibility(pad: &Padded, info: &[Info]) -> u64 {
    result
 }
 #[cfg(test)]
-mod leaf_culling_tests;
-#[cfg(test)]
 mod particle_tests;
 #[cfg(test)]
 mod visibility_tests;
@@ -277,7 +275,6 @@ struct Info {
    overlay: bool,
    /// `LeavesBlock`: with opaque leaves the faces between two leaf blocks are skipped.
    leaves: bool,
-    mangrove_roots: bool,
    blocks_flow: bool,
    ice: bool,
    sturdy: u8,
@@ -440,7 +437,6 @@ impl MeshTables {
                legacy_solid: s.legacy_solid,
                overlay: s.has_class("HalfTransparentBlock") || s.has_class("LeavesBlock"),
                leaves: s.has_class("LeavesBlock"),
-                mangrove_roots: s.has_class("MangroveRootsBlock"),
                blocks_flow: assets.blocks_fluid_flow.contains(&*s.name),
                ice: s.has_class("IceBlock"),
                sturdy: s.sturdy_full,
@@ -692,8 +688,6 @@ pub struct Mesher<'a> {
    pub smooth_lighting: bool,
    /// The `cutoutLeaves` option (fancy graphics); off makes leaves opaque.
    pub cutout_leaves: bool,
-    /// Cull shared leaf and mangrove-root faces, including transparent leaves.
-    pub cull_leaves: bool,
 }
 impl Mesher<'_> {
    /// `region[dz][dx]` are the chunks around the meshed column (centre 1,1).
@@ -773,12 +767,9 @@ impl Mesher<'_> {
                        let [dx, dy, dz] = d.normal();
                        let neighbor = pad.blocks[pi(x + dx, y + dy, z + dz)];
                        let other = &info[neighbor as usize];
-                        // Adapted from CullLeaves (MIT); see THIRD_PARTY_NOTICES.md.
-                        let shared_foliage = (state.leaves
-                            && other.leaves
-                            && (!self.cutout_leaves || self.cull_leaves))
-                            || (self.cull_leaves && state.mangrove_roots && other.mangrove_roots);
-                        visible[d as usize] = !shared_foliage
+                        // LeavesBlock.skipRendering with opaque leaves.
+                        let opaque_leaves = !self.cutout_leaves && state.leaves && other.leaves;
+                        visible[d as usize] = !opaque_leaves
                            && self
                                .visibility
                                .should_render_face(
@@ -1,126 +0,0 @@
-use super::*;
-use horizon_assets::model::Direction as ModelDirection;
-
-#[test]
-fn leaf_culling_removes_only_internal_leaf_and_root_faces() {
-    let root =
-        std::path::Path::new(env!("CARGO_MANIFEST_DIR")).join("../../.local/horizon-client/26.3");
-    if !root.join("horizon-resources.json").exists() {
-        return;
-    }
-    let assets = Assets::load(&root).unwrap();
-    let render = assets.reload(&root).unwrap();
-    let facts = BlockFacts::load(&root, assets.registry).unwrap();
-    let visibility = crate::models::load_visibility(&root, assets.registry).unwrap();
-    let tables = MeshTables::new(&assets, &render, &facts, visibility.clone()).unwrap();
-    let biomes = Biomes::load(&root).unwrap();
-    let state = |name| assets.registry.default_state(name).unwrap().0;
-    let oak = state("minecraft:oak_leaves");
-    let birch = state("minecraft:birch_leaves");
-    let roots = state("minecraft:mangrove_roots");
-    let stone = state("minecraft:stone");
-    let mesh = |blocks: &[([i32; 3], u32)], cull_leaves, cutout_leaves| {
-        let mut center = Chunk::empty(0, 0);
-        let mut east = Chunk::empty(1, 0);
-        for &([x, y, z], state) in blocks {
-            let chunk = if x < 16 { &mut center } else { &mut east };
-            chunk.set(x, y, z, state);
-        }
-        let mut region = [[None; 3]; 3];
-        region[1][1] = Some(&center);
-        region[1][2] = Some(&east);
-        Mesher {
-            nether_shading: false,
-            assets: &assets,
-            render: &render,
-            tables: &tables,
-            biomes: &biomes,
-            visibility: visibility.clone(),
-            zoom: BiomeZoom::new(0),
-            blend_radius: 0,
-            smooth_lighting: false,
-            cutout_leaves,
-            cull_leaves,
-        }
-        .tesselate(&region, (0 - MIN_Y) / 16)
-        .solid
-    };
-
-    // Native leaves can contain unculled interior geometry as well as their
-    // outer faces. Select the touching cull group from the actual baked model,
-    // preserving every other quad and its full vertex attributes.
-    let without_face = |at: [i32; 3], id, direction| {
-        let vertices = mesh(&[(at, id)], false, true);
-        let models = render
-            .model_catalog
-            .collect(BlockStateId(id), BlockPos::new(at[0], at[1], at[2]))
-            .unwrap();
-        let faces: Vec<_> = models.iter().flat_map(|(_, model)| &model.faces).collect();
-        assert_eq!(vertices.len(), faces.len() * 4);
-        let retained: Vec<_> = vertices
-            .as_chunks::<4>()
-            .0
-            .iter()
-            .zip(faces)
-            .filter(|(_, face)| face.quad.cull != Some(direction))
-            .flat_map(|(quad, _)| quad.iter().copied())
-            .collect();
-        assert!(retained.len() < vertices.len(), "fixture has a cull group");
-        retained
-    };
-
-    // Same-species leaves, mixed leaves and roots hide only their touching
-    // model groups. Disabling the option restores the isolated models.
-    for (a, b) in [(oak, oak), (oak, birch), (roots, roots)] {
-        let blocks = [([7, 7, 7], a), ([8, 7, 7], b)];
-        let off = mesh(&blocks, false, true);
-        let on = mesh(&blocks, true, true);
-        assert_eq!(
-            off.len(),
-            mesh(&[blocks[0]], false, true).len() + mesh(&[blocks[1]], false, true).len()
-        );
-        let mut retained = without_face(blocks[0].0, a, ModelDirection::East);
-        retained.extend(without_face(blocks[1].0, b, ModelDirection::West));
-        assert_eq!(
-            bytemuck::cast_slice::<_, u8>(&on),
-            bytemuck::cast_slice::<_, u8>(&retained)
-        );
-    }
-
-    // Roots do not join leaves into a single culling group. Ordinary opaque
-    // neighbors also keep their existing occlusion behavior.
-    for (a, b) in [(oak, roots), (roots, oak), (oak, stone)] {
-        let blocks = [([7, 7, 7], a), ([8, 7, 7], b)];
-        let off = mesh(&blocks, false, true);
-        let on = mesh(&blocks, true, true);
-        assert_eq!(
-            bytemuck::cast_slice::<_, u8>(&on),
-            bytemuck::cast_slice::<_, u8>(&off)
-        );
-    }
-
-    // Opaque leaves already hide internal leaf faces independently of this
-    // option, and a leaf beside air retains its complete baked model.
-    let pair = [([7, 7, 7], oak), ([8, 7, 7], birch)];
-    assert_eq!(
-        mesh(&pair, false, false).len(),
-        mesh(&pair, true, false).len()
-    );
-    let isolated = [([7, 7, 7], oak)];
-    assert_eq!(
-        bytemuck::cast_slice::<_, u8>(&mesh(&isolated, false, true)),
-        bytemuck::cast_slice::<_, u8>(&mesh(&isolated, true, true))
-    );
-
-    // The padding read must also remove the center chunk's internal face
-    // against a different leaf species in the neighboring chunk.
-    let boundary = [([15, 7, 7], oak), ([16, 7, 7], birch)];
-    assert_eq!(
-        mesh(&boundary, false, true).len(),
-        mesh(&[boundary[0]], false, true).len()
-    );
-    assert_eq!(
-        bytemuck::cast_slice::<_, u8>(&mesh(&boundary, true, true)),
-        bytemuck::cast_slice::<_, u8>(&without_face(boundary[0].0, oak, ModelDirection::East))
-    );
-}
@@ -87,7 +87,6 @@ fn info(solid: bool) -> Info {
        legacy_solid: false,
        overlay: false,
        leaves: false,
-        mangrove_roots: false,
        blocks_flow: false,
        ice: false,
        sturdy: 0,
@@ -736,9 +736,13 @@ pub struct Extra {
    /// The sniffer's and the ghastling's brain.
    pub animal_brain: Option<Box<animal_brain::Brain>>,
    pub axolotl: axolotl::Animation,
-    /// The mob this one rides, and the mob riding it (`getVehicle`, `getFirstPassenger`).
+    /// The mob or boat this one rides, and the mob riding it (`getVehicle`,
+    /// `getFirstPassenger`).
    pub mount: Option<u32>,
    pub rider: Option<u32>,
+    /// `Entity.boardingCooldown`: ticks after leaving a boat before a boat
+    /// can pick this mob up again.
+    pub boarding_cooldown: i32,
    /// A chicken carrying a zombie (`IsChickenJockey`).
    pub jockey: bool,
    /// A skeleton horse waiting to spring its trap, and how long it has waited.
@@ -987,6 +991,12 @@ pub enum MobEvent {
        pos: [i32; 3],
        state: horizon_world::registry::BlockStateId,
    },
+    /// `DoorBlock.setOpen` by a mob (`InteractWithDoor`): the door opens or
+    /// closes, both halves, with its sound and game event.
+    SetDoorOpen {
+        pos: [i32; 3],
+        open: bool,
+    },
    /// Destroy a block, dropping nothing (sheep eating grass becomes dirt via SetBlock).
    BreakBlock {
        pos: [i32; 3],
@@ -1602,6 +1612,8 @@ impl Mob {
                | Species::Fox
                | Species::Panda
        );
+        // The PathNavigation constructor: the base follow range.
+        mob.ai.nav.max_visited_nodes = (mob.kind.follow_range * 16.0).floor() as i32;
        ai::register(&mut mob);
        mob
    }
@@ -2277,7 +2289,7 @@ mod sensor_scan_tests {
    use horizon_core::geometry::Vec3;
    use serde_json::json;

-    fn kind() -> Arc<MobType> {
+    pub(super) fn kind() -> Arc<MobType> {
        Arc::new(MobType {
            id: "minecraft:cow".into(),
            species: Species::Cow,
@@ -2481,56 +2493,9 @@ mod sensor_scan_tests {
 }
 #[cfg(test)]
 mod push_tests {
+    use super::sensor_scan_tests::kind;
    use super::*;
    use horizon_core::geometry::Vec3;
-    use serde_json::json;
-
-    fn kind() -> Arc<MobType> {
-        Arc::new(MobType {
-            id: "minecraft:cow".into(),
-            species: Species::Cow,
-            width: 0.9,
-            height: 1.4,
-            eye_height: 1.3,
-            category: "creature".into(),
-            max_health: 10.0,
-            speed: 0.2,
-            flying_speed: 0.4,
-            attack_damage: 0.0,
-            attack_knockback: 0.0,
-            follow_range: 16.0,
-            step_height: 0.6,
-            armor: 0.0,
-            armor_toughness: 0.0,
-            knockback_resistance: 0.0,
-            jump_strength: 0.42,
-            attributes: Arc::default(),
-            gravity: 0.08,
-            safe_fall_distance: 3.0,
-            fall_damage_multiplier: 1.0,
-            water_efficiency: 0.0,
-            water_slowdown: 0.8,
-            air_speed: 0.02,
-            baby_scale: 0.5,
-            head_rot_speed: 10.0,
-            max_head_x_rot: 40.0,
-            max_head_y_rot: 75.0,
-            ambient_interval: 120,
-            flags: Flags {
-                animal: true,
-                ..Default::default()
-            },
-            model: Arc::new(Part::parse("root", &json!({}))),
-            layers: HashMap::new(),
-            texture: String::new(),
-            brain: Brain::Passive,
-            anim: Anim::Rabbit,
-            sounds: [""; 3],
-            step_sound: None,
-            food: Arc::default(),
-            tempt: Arc::default(),
-        })
-    }

    /// The pending pushes as one list, scanned for each mob, as before.
    fn take_old(events: &mut Vec<MobEvent>, from: usize, pending: &mut Vec<(u32, Vec3)>) {
@@ -405,7 +405,7 @@ pub fn tick(
    }
    // Mob.tickHeadTurn -> BodyRotationControl.clientTick (a frozen
    // creaking's waits).
-    if m.alive() && !(super::creaking::is_creaking(m) && !super::creaking::can_move(m)) {
+    if m.alive() && (!super::creaking::is_creaking(m) || super::creaking::can_move(m)) {
        m.body_rotation_tick();
    }
    events.append(&mut m.outbox);
@@ -752,8 +752,8 @@ impl Mob {
    pub fn pushable(&self) -> bool {
        self.alive()
            && !matches!(self.species(), Species::Bat | Species::Shulker)
-            && !(self.kind.flags.climber && self.climbing)
-            && !(self.species() == Species::Creaking && !super::creaking::can_move(self))
+            && (!self.kind.flags.climber || !self.climbing)
+            && (self.species() != Species::Creaking || super::creaking::can_move(self))
    }
 }
 /// LivingEntity.onClimbable for the pusher (Spider.onClimbable: climbing a wall).
@@ -780,7 +780,7 @@ fn push_entities(m: &mut Mob, w: &MobWorld, events: &mut Vec<MobEvent>) {
    let self_pushable = m.alive()
        && m.species() != Species::Shulker
        && !on_climbable(m, w)
-        && !(m.species() == Species::Creaking && !super::creaking::can_move(m));
+        && (m.species() != Species::Creaking || super::creaking::can_move(m));
    let mut targets: Vec<(Who, Vec3)> = Vec::new();
    if let Some(p) = &w.player
        // Entity.push: passengers of the same vehicle never push each other.