From add58fb00d73495655243c4cf13b730bbc1b3242 Mon Sep 17 00:00:00 2001 From: Eldred Habert Date: Sun, 3 Mar 2019 17:27:35 +0100 Subject: [PATCH] Fix "100% secondary effect" fix, add compatibility The original fix was bugged (example: erroneous `pop hl` if `.failed` was jumped to). Replaced with a less invasive fix, keeping all side effects from the original function; it's less intuitive, but more performant - and the tricky bit has been commented. Also the new fix is more friendly to the compatibility patch I also added, by request of ShinyDragonHunter. --- docs/bugs_and_glitches.md | 30 ++++++++++++++++++++++-------- 1 file changed, 22 insertions(+), 8 deletions(-) diff --git a/docs/bugs_and_glitches.md b/docs/bugs_and_glitches.md index f58d2a06b..020090329 100644 --- a/docs/bugs_and_glitches.md +++ b/docs/bugs_and_glitches.md @@ -175,24 +175,38 @@ This bug existed for all battles in Gold and Silver, and was only fixed for sing ```diff - ; BUG: 1/256 chance to fail even for a 100% effect chance, - ; since carry is not set if BattleRandom == [hl] == 255 +- call BattleRandom + ld a, [hl] -+ cp 100 percent -+ jr z, .ok - call BattleRandom ++ sub 100 percent ++ ; If chance was 100%, RNG won't be called (carry not set) ++ ; Thus chance will be subtracted from 0, guaranteeing a carry ++ call c, BattleRandom cp [hl] -- pop hl -- ret c -+ jr c, .ok + pop hl + ret c .failed ld a, 1 ld [wEffectFailed], a and a -+.ok -+ pop hl ret ``` +If you wish to keep compatibility with standard Pokémon Crystal, you can disable the fix during link battles by also applying the following edit in the same place: + +```diff ++ ld a, [wLinkMode] ++ cp LINK_COLOSSEUM ++ scf ; Force RNG to be called ++ jr z, .nofix ; Don't apply fix in link battles, for compatibility + ld a, [hl] + sub 100 percent + ; If chance was 100%, RNG won't be called (carry not set) + ; Thus chance will be subtracted from 0, guaranteeing a carry ++ .nofix + call c, BattleRandom +``` + ## Belly Drum sharply boosts Attack even with under 50% HP *Fixing this bug will break compatibility with standard Pokémon Crystal for link battles.*