Hopefully illusion works as intended now

charmap.txt

@@ -407,6 +407,8 @@ B_ATK_TEAM2 = FD 38
 B_DEF_NAME = FD 39
 B_DEF_TEAM1 = FD 3A
 B_DEF_TEAM2 = FD 3B
+B_ACTIVE_NAME = FD 3C
+B_ACTIVE_NAME2 = FD 3D @ no Illusion check
 
 @ indicates the end of a town/city name (before " TOWN" or " CITY")
 NAME_END = FC 00

data/battle_scripts_1.s

@@ -4946,6 +4946,7 @@ BattleScript_FaintedMonTryChooseAnother:
 	jumpifword CMP_COMMON_BITS, gHitMarker, HITMARKER_x400000, BattleScript_FaintedMonChooseAnother
 	jumpifbyte CMP_EQUAL, sBATTLE_STYLE, 0x1, BattleScript_FaintedMonChooseAnother
 	jumpifcantswitch BS_PLAYER1, BattleScript_FaintedMonChooseAnother
+	setbyte sILLUSION_NICK_HACK, 1
 	printstring STRINGID_ENEMYABOUTTOSWITCHPKMN
 	setbyte gBattleCommunication, 0x0
 	yesnobox

include/battle.h

@@ -429,9 +429,10 @@ struct MegaEvolutionData
 
 struct Illusion
 {
-    u8 on:1;
+    u8 on;
-    u8 broken:1;
+    u8 set;
-    u8 partyId:3;
+    u8 broken;
+    u8 partyId;
     struct Pokemon *mon;
 };
 
@@ -616,6 +617,7 @@ struct BattleScripting
     u16 savedMoveEffect; // For moves hitting multiple targets.
     u16 moveEffect;
     u16 multihitMoveEffect;
+    u8 illusionNickHack; // To properly display nick in STRINGID_ENEMYABOUTTOSWITCHPKMN.
 };
 
 // rom_80A5C6C

include/battle_message.h

@@ -64,6 +64,8 @@
 #define B_TXT_DEF_NAME 0x39
 #define B_TXT_DEF_TEAM1 0x3A // Your/The opposing
 #define B_TXT_DEF_TEAM2 0x3B // your/the opposing
+#define B_TXT_ACTIVE_NAME 0x3C
+#define B_TXT_ACTIVE_NAME2 0x3D // no Illusion check
 
 // for B_TXT_BUFF1, B_TXT_BUFF2 and B_TXT_BUFF3
 

include/constants/battle_script_commands.h

@@ -34,6 +34,7 @@
 #define sSAVED_MOVE_EFFECT gBattleScripting + 0x2C
 #define sMOVE_EFFECT gBattleScripting + 0x2E
 #define sMULTIHIT_EFFECT gBattleScripting + 0x30
+#define sILLUSION_NICK_HACK gBattleScripting + 0x32
 
 #define cMULTISTRING_CHOOSER gBattleCommunication + 5
 

src/battle_gfx_sfx_util.c

@@ -411,7 +411,7 @@ bool8 TryHandleLaunchBattleTableAnimation(u8 activeBattler, u8 atkBattler, u8 de
     }
 
     if (tableId == B_ANIM_ILLUSION_OFF)
-        ClearIllusionMon(activeBattler);
+        gBattleStruct->illusion[activeBattler].broken = 1;
 
     gBattleAnimAttacker = atkBattler;
     gBattleAnimTarget = defBattler;
@@ -1158,11 +1158,6 @@ void ClearTemporarySpeciesSpriteData(u8 battlerId, bool8 dontClearSubstitute)
     gBattleMonForms[battlerId] = 0;
     if (!dontClearSubstitute)
         ClearBehindSubstituteBit(battlerId);
-
-    if (GetBattlerSide(battlerId) == B_SIDE_PLAYER)
-        SetIllusionMon(&gPlayerParty[gBattlerPartyIndexes[battlerId]], battlerId);
-    else
-        SetIllusionMon(&gEnemyParty[gBattlerPartyIndexes[battlerId]], battlerId);
 }
 
 void AllocateMonSpritesGfx(void)

src/battle_main.c

@@ -2971,6 +2971,7 @@ void SwitchInClearSetData(void)
     s32 i;
     struct DisableStruct disableStructCopy = gDisableStructs[gActiveBattler];
 
+    ClearIllusionMon(gActiveBattler);
     if (gBattleMoves[gCurrentMove].effect != EFFECT_BATON_PASS)
     {
         for (i = 0; i < NUM_BATTLE_STATS; i++)

src/battle_message.c

@@ -19,6 +19,7 @@
 #include "text.h"
 #include "trainer_hill.h"
 #include "window.h"
+#include "constants/abilities.h"
 #include "constants/battle_string_ids.h"
 #include "constants/frontier_util.h"
 #include "constants/items.h"
@@ -1529,7 +1530,7 @@ const u8 gText_PkmnIsEvolving[] = _("What?\n{STR_VAR_1} is evolving!");
 const u8 gText_CongratsPkmnEvolved[] = _("Congratulations! Your {STR_VAR_1}\nevolved into {STR_VAR_2}!{WAIT_SE}\p");
 const u8 gText_PkmnStoppedEvolving[] = _("Huh? {STR_VAR_1}\nstopped evolving!\p");
 const u8 gText_EllipsisQuestionMark[] = _("……?\p");
-const u8 gText_WhatWillPkmnDo[] = _("What will\n{B_ACTIVE_NAME_WITH_PREFIX} do?");
+const u8 gText_WhatWillPkmnDo[] = _("What will\n{B_ACTIVE_NAME2} do?");
 const u8 gText_WhatWillPkmnDo2[] = _("What will\n{B_PLAYER_NAME} do?");
 const u8 gText_WhatWillWallyDo[] = _("What will\nWALLY do?");
 const u8 gText_LinkStandby[] = _("{PAUSE 16}Link standby…");
@@ -2919,6 +2920,18 @@ u32 BattleStringExpandPlaceholders(const u8 *src, u8 *dst)
                 GetBattlerNick(gBattlerTarget, text);
                 toCpy = text;
                 break;
+            case B_TXT_ACTIVE_NAME: // active name
+                GetBattlerNick(gActiveBattler, text);
+                toCpy = text;
+                break;
+            case B_TXT_ACTIVE_NAME2: // active battlerId name with prefix, no illusion
+                if (GetBattlerSide(gActiveBattler) == B_SIDE_PLAYER)
+                    GetMonData(&gPlayerParty[gBattlerPartyIndexes[gActiveBattler]], MON_DATA_NICKNAME, text);
+                else
+                    GetMonData(&gEnemyParty[gBattlerPartyIndexes[gActiveBattler]], MON_DATA_NICKNAME, text);
+                StringGetEnd10(text);
+                toCpy = text;
+                break;
             case B_TXT_EFF_NAME_WITH_PREFIX: // effect battlerId name with prefix
                 HANDLE_NICKNAME_STRING_CASE(gEffectBattler)
                 break;
@@ -3234,6 +3247,37 @@ u32 BattleStringExpandPlaceholders(const u8 *src, u8 *dst)
     return dstID;
 }
 
+static void IllusionNickHack(u32 battlerId, u32 partyId, u8 *dst)
+{
+    s32 id, i;
+    // we know it's gEnemyParty
+    struct Pokemon *mon = &gEnemyParty[partyId], *partnerMon;
+
+    if (GetMonAbility(mon) == ABILITY_ILLUSION)
+    {
+        if (IsBattlerAlive(BATTLE_PARTNER(battlerId)))
+            partnerMon = &gEnemyParty[gBattlerPartyIndexes[BATTLE_PARTNER(battlerId)]];
+        else
+            partnerMon = mon;
+
+        // Find last alive non-egg pokemon.
+        for (i = PARTY_SIZE - 1; i >= 0; i--)
+        {
+            id = i;
+            if (GetMonData(&gEnemyParty[id], MON_DATA_SANITY_HAS_SPECIES)
+                && GetMonData(&gEnemyParty[id], MON_DATA_HP)
+                && &gEnemyParty[id] != mon
+                && &gEnemyParty[id] != partnerMon)
+            {
+                GetMonData(&gEnemyParty[id], MON_DATA_NICKNAME, dst);
+                return;
+            }
+        }
+    }
+
+    GetMonData(mon, MON_DATA_NICKNAME, dst);
+}
+
 static void ExpandBattleTextBuffPlaceholders(const u8 *src, u8 *dst)
 {
     u32 srcID = 1;
@@ -3306,6 +3350,12 @@ static void ExpandBattleTextBuffPlaceholders(const u8 *src, u8 *dst)
             {
                 GetBattlerNick(src[srcID + 1], dst);
             }
+            else if (gBattleScripting.illusionNickHack) // for STRINGID_ENEMYABOUTTOSWITCHPKMN
+            {
+                gBattleScripting.illusionNickHack = 0;
+                IllusionNickHack(src[srcID + 1], src[srcID + 2], dst);
+                StringGetEnd10(dst);
+            }
             else
             {
                 if (GetBattlerSide(src[srcID + 1]) == B_SIDE_PLAYER)

src/battle_util.c

@@ -3802,7 +3802,7 @@ u8 AbilityBattleEffects(u8 caseID, u8 battler, u8 ability, u8 special, u16 moveA
             }
             break;
         case ABILITY_ILLUSION:
-            if (gBattleStruct->illusion[battler].on && !gBattleStruct->illusion[battler].broken && IsBattlerAlive(battler) && TARGET_TURN_DAMAGED)
+            if (gBattleStruct->illusion[gBattlerTarget].on && !gBattleStruct->illusion[gBattlerTarget].broken && TARGET_TURN_DAMAGED)
             {
                 BattleScriptPushCursor();
                 gBattlescriptCurrInstr = BattleScript_IllusionOff;
@@ -6750,7 +6750,16 @@ bool32 CanBattlerGetOrLoseItem(u8 battlerId, u16 itemId)
 
 struct Pokemon *GetIllusionMonPtr(u32 battlerId)
 {
-    if (!gBattleStruct->illusion[battlerId].on || gBattleStruct->illusion[battlerId].broken)
+    if (gBattleStruct->illusion[battlerId].broken)
+        return NULL;
+    if (!gBattleStruct->illusion[battlerId].set)
+    {
+        if (GetBattlerSide(battlerId) == B_SIDE_PLAYER)
+            SetIllusionMon(&gPlayerParty[gBattlerPartyIndexes[battlerId]], battlerId);
+        else
+            SetIllusionMon(&gEnemyParty[gBattlerPartyIndexes[battlerId]], battlerId);
+    }
+    if (!gBattleStruct->illusion[battlerId].on)
         return NULL;
 
     return gBattleStruct->illusion[battlerId].mon;
@@ -6758,9 +6767,7 @@ struct Pokemon *GetIllusionMonPtr(u32 battlerId)
 
 void ClearIllusionMon(u32 battlerId)
 {
-    gBattleStruct->illusion[battlerId].on = 0;
+    memset(&gBattleStruct->illusion[battlerId], 0, sizeof(gBattleStruct->illusion[battlerId]));
-    gBattleStruct->illusion[battlerId].mon = NULL;
-    gBattleStruct->illusion[battlerId].broken = 1;
 }
 
 bool32 SetIllusionMon(struct Pokemon *mon, u32 battlerId)
@@ -6768,6 +6775,7 @@ bool32 SetIllusionMon(struct Pokemon *mon, u32 battlerId)
     struct Pokemon *party, *partnerMon;
     s32 i, id;
 
+    gBattleStruct->illusion[battlerId].set = 1;
     if (GetMonAbility(mon) != ABILITY_ILLUSION)
         return FALSE;
 
@@ -6784,7 +6792,7 @@ bool32 SetIllusionMon(struct Pokemon *mon, u32 battlerId)
     // Find last alive non-egg pokemon.
     for (i = PARTY_SIZE - 1; i >= 0; i--)
     {
-        id = GetPartyIdFromBattlePartyId(i);
+        id = i;
         if (GetMonData(&party[id], MON_DATA_SANITY_HAS_SPECIES)
             && GetMonData(&party[id], MON_DATA_HP)
             && &party[id] != mon