diff --git a/docs/emulation-bug-hunt-todos.md b/docs/emulation-bug-hunt-todos.md
index 28b2b1b2..b402dd47 100644
--- a/docs/emulation-bug-hunt-todos.md
+++ b/docs/emulation-bug-hunt-todos.md
@@ -77,6 +77,17 @@ describe guesses, timing gaps, or known emulation shortcuts.
   road/ground rendering.
 ## Medium Priority
 
+- **Battle Sphere (accurate blitter):** HUD elements can show **solid black**
+  inside shapes where the framebuffer should still show the scene (e.g. cockpit
+  reticles / targeting squares). User reports this with the **default accurate**
+  blitter (`BlitterMidsummer2`); enabling **Fast blitter** (`virtualjaguar_usefastblitter`)
+  may avoid it because `blitter_blit` uses a separate code path
+  (`src/tom/blitter_mmio.c` dispatches on `vjs.useFastBlitter`). Likely involves
+  **16-bit CRY**, **DCOMPEN** (color key / pattern compare), or **phrase-mode**
+  `COMP_CTRL` + `byte_merge` (`src/tom/blitter.c` `DATA()`, `blitter_simd_scalar.c`)
+  not matching hardware for inner pixels. Needs a logged COMMAND/A1/A2 register
+  dump from one bad blit for a targeted fix.
+
 - `src/tom/tom.c`: replace hard-coded visible-window constants with values
   derived from TOM timing registers where possible. This should be tested
   against NTSC, PAL, and games that reprogram HDB/HDE/VDB/VDE.
diff --git a/src/tom/blitter.c b/src/tom/blitter.c
index 01560b41..c084b972 100644
--- a/src/tom/blitter.c
+++ b/src/tom/blitter.c
@@ -1686,9 +1686,13 @@ A2ptrldi	:= NAN2 (a2ptrldi, a2update\, a2pldt);*/
                   Start and end from the address level of the pipeline are used.
                   */
 
-               //Phrase mode needs destination data for start/end mask byte merging,
-               //but NOT when bkgwren is set (hardware uses DSTDATA register value).
-               if (phrase_mode && !dsten && !bkgwren)
+               /* Phrase writes merge via byte_merge(mask): inhibited bytes come from
+                * dstd. With !DSTEN the dread path never runs (all dread strobes need
+                * dsten), so dstd would stay at DSTDATA — often 0 — and keyed/HUD
+                * pixels show black boxes. With DSTEN, dread usually fills dstd, but
+                * reloading here guarantees merge uses the current phrase at `address`
+                * for every dwrite (same as framebuffer under this blit). */
+               if (phrase_mode)
                   dstd = ((uint64_t)JaguarReadLong(address, BLITTER) << 32) | (uint64_t)JaguarReadLong(address + 4, BLITTER);
 
                // Write data combines srcd and dstd through ADDDSEL, PATDSEL, or LFU.