Merge pull request #118 from Lorenzooone/Poisoning

Fix poisoning bugs

notes/m2-notes.txt

@@ -18,7 +18,8 @@ English names:
 - Jeff: 7A 95 96 96
 - Poo:  80 9F 9F
 
-0x2020C70: enemy data slots in-battle? separated by 0x94 bytes
+0x2020C70: party character slots in battle. 0x94 bytes long
+0x2021110: enemy slots in battle. 0x94 bytes long
 0x2025038: enemy count (initial, not current)
 0x20251D8: item drop
 0x3000A00: Current PSI list when displaying a PSI window?

src/m2-bugfixes.asm

@@ -0,0 +1,57 @@
+//==============================================================================
+//Fixes the issue where Gyigas and other enemies would not use their death attack
+//(or phase change) because of the poison
+dee6c_fix_poison_gyigas:
+push    {lr}
+
+bl      0x80E9CFC //Normal code
+
+ldr     r2,=#0x2024860 //Where the action's data is stored
+ldr     r0,[r6,#0] //Load the entity's slot
+add     r0,#0x44
+ldrh    r1,[r0,#0]
+cmp     r1,#0
+beq     @@normal //Characters have this set as 0
+cmp     r1,#0xDA //This particular Gyigas phase does not need this... (It will reflect the poison randomly if we let it continue)
+beq     @@normal
+ldrh    r1,[r0,#4] // Get the enemy's current HP
+cmp     r1,#0 //Check if they're 0
+bne     @@normal
+ldrh    r1,[r0,#6] // Get the enemy's scrolling HP
+cmp     r1,#0 //Check if they're 0 (probably not needed)
+bne     @@normal
+mov     r0,#0x9 //Fabricate a death check for the enemy
+add     r2,#0x16
+strh    r0,[r2,#0]
+mov     r0,#0
+strh    r0,[r2,#4]
+mov     r0,#4 //This counts as a PSI, since setting it as a normal attack would make it so the Diamond Dog would reflect it
+strh    r0,[r2,#6]
+add     r2,#0xC
+strh    r0,[r2,#0x6]
+mov     r0,#1
+strh    r0,[r2,#4]
+mov     r0,#0
+strh    r0,[r2,#0]
+add     r2,#0x24
+strh    r0,[r2,#0]
+strh    r0,[r2,#0x12]
+ldr     r2,=#0x2025034
+mov     r0,#1
+strh    r0,[r2,#0] //This is a PSI. Not a physical attack
+ldr     r0,=#0x3005378
+mov     r1,#0xC //This is PSI Cool Thing
+strh    r1,[r0,#0]
+mov     r1,#0
+strh    r1,[r0,#0x10]
+b       @@end
+
+@@normal:
+mov     r0,#0x64 //Normal game's behaviour
+strh    r0,[r2,#0x16]
+
+@@end:
+pop     {pc}
+
+
+//==============================================================================

src/m2-hack.asm

@@ -1710,6 +1710,11 @@ nop
 .org 0x8731046 :: dh 00h
 
 
+//==============================================================================
+// Fix Gyigas' poison bug
+//==============================================================================
+.org 0x80DEE6C :: bl dee6c_fix_poison_gyigas :: nop :: nop :: nop
+
 //==============================================================================
 // Move stuff around in order to make space for the code
 //==============================================================================
@@ -1975,6 +1980,7 @@ disclaimer_map:
 .include "syscalls.asm"
 .include "m2-vwf.asm"
 .include "m2-vwf-entries.asm"
+.include "m2-bugfixes.asm"
 .include "m2-formatting.asm"
 .include "m2-customcodes.asm"
 .include "m2-compiled.asm"