From 0d490e57d36915014935a9e3509f5533ff4b96f3 Mon Sep 17 00:00:00 2001
From: robjlyons <81177492+robjlyons@users.noreply.github.com>
Date: Wed, 11 Feb 2026 10:55:52 +0000
Subject: [PATCH 01/12] Fix overworld poison-faint run-away handling

---
 engine/events/poison.asm | 32 +++-----------------------------
 1 file changed, 3 insertions(+), 29 deletions(-)

diff --git a/engine/events/poison.asm b/engine/events/poison.asm
index 9d87b3ca..f3c66345 100644
--- a/engine/events/poison.asm
+++ b/engine/events/poison.asm
@@ -68,7 +68,9 @@ ApplyOutOfBattlePoisonDamage:
 	callfar PlayPikachuSoundClip
 	callfar_ModifyPikachuHappiness PIKAHAPPY_PSNFNT
 .curMonNotPlayerPikachu
-	call HandlePoisonFaintedMonRanAway
+	ld a, [wWhichPokemon]
+	ld [wPlayerMonNumber], a
+	callfar HandleFaintedPlayerMonRanAway
 	pop de
 	pop hl
 	jr .restartAfterRemoval
@@ -148,34 +150,6 @@ ApplyOutOfBattlePoisonDamage:
 	ld [wOutOfBattleBlackout], a
 	ret
 
-PoisonFaintedMonRanAwayText:
-	text_far _PokemonRanAwayBadTrainingText
-	text_end
-
-HandlePoisonFaintedMonRanAway:
-	ld a, [wPartyCount]
-	cp 1
-	ret z ; don't remove the final party mon to avoid invalid 0-mon party state
-	ld hl, wPartyMonNicks
-	call GetPartyMonName
-	ld hl, PoisonFaintedMonRanAwayText
-	call PrintText
-	xor a
-	ld [wRemoveMonFromBox], a
-	call RemovePokemon
-	ld a, [wPartyCount]
-	and a
-	ret z
-	dec a
-	ld b, a
-	ld a, [wWhichPokemon]
-	cp b
-	jr c, .done
-	ld a, b
-	ld [wWhichPokemon], a
-.done
-	ret
-
 Func_c4c7:
 	ld a, [wStepCounter]
 	and a

From 9f66b83ada62eeb34f3852ddab849910513b88b5 Mon Sep 17 00:00:00 2001
From: robjlyons <81177492+robjlyons@users.noreply.github.com>
Date: Wed, 11 Feb 2026 11:56:47 +0000
Subject: [PATCH 02/12] Also block catches for species already in PC boxes

---
 engine/battle/core.asm   | 109 +++++++++++++++++++++++++++++++++++++++
 engine/events/poison.asm |  32 ++----------
 2 files changed, 112 insertions(+), 29 deletions(-)

diff --git a/engine/battle/core.asm b/engine/battle/core.asm
index f13ed4b7..0d7300c0 100644
--- a/engine/battle/core.asm
+++ b/engine/battle/core.asm
@@ -170,6 +170,9 @@ StartBattle:
 	ld a, c
 	and a
 	jr z, .skipWildCatchInit
+	call IsEnemyMonSpeciesInPlayerCollection
+	and a
+	jr nz, .skipWildCatchInit
 	ld a, 1
 	ld [wWildEncounterCanCatch], a
 .skipWildCatchInit
@@ -1207,6 +1210,112 @@ DisableEncounterCatchSRAM_Battle:
     ld [$0000], a                 ; disable SRAM
     ret
 
+; Returns non-zero if the current wild enemy species is in the player's party or PC boxes.
+IsEnemyMonSpeciesInPlayerCollection:
+	call IsEnemyMonSpeciesInPlayerParty
+	and a
+	ret nz
+	call IsEnemyMonSpeciesInAnyPlayerPCBox
+	and a
+	ret
+
+; Returns non-zero if the current wild enemy species is already present in the player's party.
+IsEnemyMonSpeciesInPlayerParty:
+	ld a, [wPartyCount]
+	ld c, a
+	ld hl, wPartySpecies
+.loop
+	ld a, c
+	and a
+	jr z, .notInParty
+	ld a, [hli]
+	ld b, a
+	ld a, [wEnemyMonSpecies]
+	cp b
+	jr z, .inParty
+	dec c
+	jr .loop
+.inParty
+	ld a, 1
+	ret
+.notInParty
+	xor a
+	ret
+
+; Returns non-zero if the current wild enemy species is present in any of the player's PC boxes.
+IsEnemyMonSpeciesInAnyPlayerPCBox:
+	ld d, 0
+.boxLoop
+	ld a, d
+	cp NUM_BOXES
+	jr z, .notInPC
+	push de
+	call IsEnemyMonSpeciesInPlayerPCBox
+	pop de
+	and a
+	jr nz, .inPC
+	inc d
+	jr .boxLoop
+.inPC
+	ld a, 1
+	ret
+.notInPC
+	xor a
+	ret
+
+; Checks one PC box.
+; in: d = box index (0 to NUM_BOXES - 1)
+; out: non-zero if the current wild enemy species exists in that box
+IsEnemyMonSpeciesInPlayerPCBox:
+	ld a, d
+	cp NUM_BOXES / 2
+	ld b, 2
+	jr c, .haveBank
+	ld b, 3
+	sub NUM_BOXES / 2
+.haveBank
+	ld e, a
+	ld d, 0
+	ld hl, BattleBoxSRAMPointerTable
+	add hl, de
+	add hl, de
+	ld a, [hli]
+	ld h, [hl]
+	ld l, a
+	call EnableSRAM
+	ld a, b
+	ld [rRAMB], a
+	ld a, [hl]
+	ld c, a
+	inc hl
+.scanSpeciesLoop
+	ld a, c
+	and a
+	jr z, .notInBox
+	ld a, [hli]
+	ld b, a
+	ld a, [wEnemyMonSpecies]
+	cp b
+	jr z, .inBox
+	dec c
+	jr .scanSpeciesLoop
+.inBox
+	call DisableSRAM
+	ld a, 1
+	ret
+.notInBox
+	call DisableSRAM
+	xor a
+	ret
+
+BattleBoxSRAMPointerTable:
+	dw sBox1 ; sBox7
+	dw sBox2 ; sBox8
+	dw sBox3 ; sBox9
+	dw sBox4 ; sBox10
+	dw sBox5 ; sBox11
+	dw sBox6 ; sBox12
+
 ; asks if you want to use next mon
 ; stores whether you ran in C flag
 DoUseNextMonDialogue:
diff --git a/engine/events/poison.asm b/engine/events/poison.asm
index 9d87b3ca..f3c66345 100644
--- a/engine/events/poison.asm
+++ b/engine/events/poison.asm
@@ -68,7 +68,9 @@ ApplyOutOfBattlePoisonDamage:
 	callfar PlayPikachuSoundClip
 	callfar_ModifyPikachuHappiness PIKAHAPPY_PSNFNT
 .curMonNotPlayerPikachu
-	call HandlePoisonFaintedMonRanAway
+	ld a, [wWhichPokemon]
+	ld [wPlayerMonNumber], a
+	callfar HandleFaintedPlayerMonRanAway
 	pop de
 	pop hl
 	jr .restartAfterRemoval
@@ -148,34 +150,6 @@ ApplyOutOfBattlePoisonDamage:
 	ld [wOutOfBattleBlackout], a
 	ret
 
-PoisonFaintedMonRanAwayText:
-	text_far _PokemonRanAwayBadTrainingText
-	text_end
-
-HandlePoisonFaintedMonRanAway:
-	ld a, [wPartyCount]
-	cp 1
-	ret z ; don't remove the final party mon to avoid invalid 0-mon party state
-	ld hl, wPartyMonNicks
-	call GetPartyMonName
-	ld hl, PoisonFaintedMonRanAwayText
-	call PrintText
-	xor a
-	ld [wRemoveMonFromBox], a
-	call RemovePokemon
-	ld a, [wPartyCount]
-	and a
-	ret z
-	dec a
-	ld b, a
-	ld a, [wWhichPokemon]
-	cp b
-	jr c, .done
-	ld a, b
-	ld [wWhichPokemon], a
-.done
-	ret
-
 Func_c4c7:
 	ld a, [wStepCounter]
 	and a

From 31e12f3b602650358aa8c6f71586de815e9eb211 Mon Sep 17 00:00:00 2001
From: robjlyons <81177492+robjlyons@users.noreply.github.com>
Date: Wed, 11 Feb 2026 12:18:31 +0000
Subject: [PATCH 03/12] Harden PC species scan for empty/uninitialized boxes

---
 engine/battle/core.asm   | 115 +++++++++++++++++++++++++++++++++++++++
 engine/events/poison.asm |  32 +----------
 2 files changed, 118 insertions(+), 29 deletions(-)

diff --git a/engine/battle/core.asm b/engine/battle/core.asm
index f13ed4b7..606e9cf6 100644
--- a/engine/battle/core.asm
+++ b/engine/battle/core.asm
@@ -170,6 +170,9 @@ StartBattle:
 	ld a, c
 	and a
 	jr z, .skipWildCatchInit
+	call IsEnemyMonSpeciesInPlayerCollection
+	and a
+	jr nz, .skipWildCatchInit
 	ld a, 1
 	ld [wWildEncounterCanCatch], a
 .skipWildCatchInit
@@ -1207,6 +1210,118 @@ DisableEncounterCatchSRAM_Battle:
     ld [$0000], a                 ; disable SRAM
     ret
 
+; Returns non-zero if the current wild enemy species is in the player's party or PC boxes.
+IsEnemyMonSpeciesInPlayerCollection:
+	call IsEnemyMonSpeciesInPlayerParty
+	and a
+	ret nz
+	call IsEnemyMonSpeciesInAnyPlayerPCBox
+	and a
+	ret
+
+; Returns non-zero if the current wild enemy species is already present in the player's party.
+IsEnemyMonSpeciesInPlayerParty:
+	ld a, [wPartyCount]
+	ld c, a
+	ld hl, wPartySpecies
+.loop
+	ld a, c
+	and a
+	jr z, .notInParty
+	ld a, [hli]
+	ld b, a
+	ld a, [wEnemyMonSpecies]
+	cp b
+	jr z, .inParty
+	dec c
+	jr .loop
+.inParty
+	ld a, 1
+	ret
+.notInParty
+	xor a
+	ret
+
+; Returns non-zero if the current wild enemy species is present in any of the player's PC boxes.
+IsEnemyMonSpeciesInAnyPlayerPCBox:
+	ld d, 0
+.boxLoop
+	ld a, d
+	cp NUM_BOXES
+	jr z, .notInPC
+	push de
+	call IsEnemyMonSpeciesInPlayerPCBox
+	pop de
+	and a
+	jr nz, .inPC
+	inc d
+	jr .boxLoop
+.inPC
+	ld a, 1
+	ret
+.notInPC
+	xor a
+	ret
+
+; Checks one PC box.
+; in: d = box index (0 to NUM_BOXES - 1)
+; out: non-zero if the current wild enemy species exists in that box
+IsEnemyMonSpeciesInPlayerPCBox:
+	ld a, d
+	cp NUM_BOXES / 2
+	ld b, 2
+	jr c, .haveBank
+	ld b, 3
+	sub NUM_BOXES / 2
+.haveBank
+	ld e, a
+	ld d, 0
+	ld hl, BattleBoxSRAMPointerTable
+	add hl, de
+	add hl, de
+	ld a, [hli]
+	ld h, [hl]
+	ld l, a
+	call EnableSRAM
+	ld a, b
+	ld [rRAMB], a
+	ld a, [hl]
+	ld c, a
+	inc hl
+	ld a, c
+	cp MONS_PER_BOX + 1
+	jr c, .scanSpeciesLoop
+	ld c, MONS_PER_BOX
+.scanSpeciesLoop
+	ld a, c
+	and a
+	jr z, .notInBox
+	ld a, [hli]
+	cp -1
+	jr z, .notInBox
+	ld b, a
+	ld a, [wEnemyMonSpecies]
+	cp b
+	jr z, .inBox
+	dec c
+	jr .scanSpeciesLoop
+.inBox
+	call DisableSRAM
+	ld a, 1
+	ret
+.notInBox
+	call DisableSRAM
+	xor a
+	ret
+
+BattleBoxSRAMPointerTable:
+	dw sBox1 ; sBox7
+	dw sBox2 ; sBox8
+	dw sBox3 ; sBox9
+	dw sBox4 ; sBox10
+	dw sBox5 ; sBox11
+	dw sBox6 ; sBox12
+
 ; asks if you want to use next mon
 ; stores whether you ran in C flag
 DoUseNextMonDialogue:
diff --git a/engine/events/poison.asm b/engine/events/poison.asm
index 9d87b3ca..f3c66345 100644
--- a/engine/events/poison.asm
+++ b/engine/events/poison.asm
@@ -68,7 +68,9 @@ ApplyOutOfBattlePoisonDamage:
 	callfar PlayPikachuSoundClip
 	callfar_ModifyPikachuHappiness PIKAHAPPY_PSNFNT
 .curMonNotPlayerPikachu
-	call HandlePoisonFaintedMonRanAway
+	ld a, [wWhichPokemon]
+	ld [wPlayerMonNumber], a
+	callfar HandleFaintedPlayerMonRanAway
 	pop de
 	pop hl
 	jr .restartAfterRemoval
@@ -148,34 +150,6 @@ ApplyOutOfBattlePoisonDamage:
 	ld [wOutOfBattleBlackout], a
 	ret
 
-PoisonFaintedMonRanAwayText:
-	text_far _PokemonRanAwayBadTrainingText
-	text_end
-
-HandlePoisonFaintedMonRanAway:
-	ld a, [wPartyCount]
-	cp 1
-	ret z ; don't remove the final party mon to avoid invalid 0-mon party state
-	ld hl, wPartyMonNicks
-	call GetPartyMonName
-	ld hl, PoisonFaintedMonRanAwayText
-	call PrintText
-	xor a
-	ld [wRemoveMonFromBox], a
-	call RemovePokemon
-	ld a, [wPartyCount]
-	and a
-	ret z
-	dec a
-	ld b, a
-	ld a, [wWhichPokemon]
-	cp b
-	jr c, .done
-	ld a, b
-	ld [wWhichPokemon], a
-.done
-	ret
-
 Func_c4c7:
 	ld a, [wStepCounter]
 	and a

From 4c4824c99a26cb0f999d8178543a0394da464fd4 Mon Sep 17 00:00:00 2001
From: robjlyons <81177492+robjlyons@users.noreply.github.com>
Date: Wed, 11 Feb 2026 12:27:26 +0000
Subject: [PATCH 04/12] Fix wild encounter crash from cross-bank SRAM calls

---
 engine/battle/core.asm   | 137 ++++++++++++++++++++++++++++++++++++---
 engine/events/poison.asm |  32 +--------
 2 files changed, 130 insertions(+), 39 deletions(-)

diff --git a/engine/battle/core.asm b/engine/battle/core.asm
index f13ed4b7..306117a6 100644
--- a/engine/battle/core.asm
+++ b/engine/battle/core.asm
@@ -170,6 +170,9 @@ StartBattle:
 	ld a, c
 	and a
 	jr z, .skipWildCatchInit
+	call IsEnemyMonSpeciesInPlayerCollection
+	and a
+	jr nz, .skipWildCatchInit
 	ld a, 1
 	ld [wWildEncounterCanCatch], a
 .skipWildCatchInit
@@ -1194,18 +1197,132 @@ EnsureEncounterCatchFlagsInitialized:
 	ret
 
 EnableEncounterCatchSRAM_Battle:
-    ld a, $0A
-    ld [$0000], a                 ; enable SRAM
-    ld a, $01
-    ld [$6000], a                 ; MBC1: RAM banking mode (harmless on others)
-    ld a, BANK(sMapEncounterCatchFlags)
-    ld [$4000], a                 ; select SRAM bank that holds the flags
-    ret
+	ld a, BMODE_ADVANCED
+	ld [rBMODE], a
+	ld a, RAMG_SRAM_ENABLE
+	ld [rRAMG], a
+	ld a, BANK(sMapEncounterCatchFlags)
+	ld [rRAMB], a
+	ret
 
 DisableEncounterCatchSRAM_Battle:
-    xor a
-    ld [$0000], a                 ; disable SRAM
-    ret
+	ld a, BMODE_SIMPLE ; preserve flags
+	ld [rBMODE], a
+	ASSERT RAMG_SRAM_DISABLE == BMODE_SIMPLE
+	ld [rRAMG], a
+	ret
+
+; Returns non-zero if the current wild enemy species is in the player's party or PC boxes.
+IsEnemyMonSpeciesInPlayerCollection:
+	call IsEnemyMonSpeciesInPlayerParty
+	and a
+	ret nz
+	call IsEnemyMonSpeciesInAnyPlayerPCBox
+	and a
+	ret
+
+; Returns non-zero if the current wild enemy species is already present in the player's party.
+IsEnemyMonSpeciesInPlayerParty:
+	ld a, [wPartyCount]
+	ld c, a
+	ld hl, wPartySpecies
+.loop
+	ld a, c
+	and a
+	jr z, .notInParty
+	ld a, [hli]
+	ld b, a
+	ld a, [wEnemyMonSpecies]
+	cp b
+	jr z, .inParty
+	dec c
+	jr .loop
+.inParty
+	ld a, 1
+	ret
+.notInParty
+	xor a
+	ret
+
+; Returns non-zero if the current wild enemy species is present in any of the player's PC boxes.
+IsEnemyMonSpeciesInAnyPlayerPCBox:
+	ld d, 0
+.boxLoop
+	ld a, d
+	cp NUM_BOXES
+	jr z, .notInPC
+	push de
+	call IsEnemyMonSpeciesInPlayerPCBox
+	pop de
+	and a
+	jr nz, .inPC
+	inc d
+	jr .boxLoop
+.inPC
+	ld a, 1
+	ret
+.notInPC
+	xor a
+	ret
+
+; Checks one PC box.
+; in: d = box index (0 to NUM_BOXES - 1)
+; out: non-zero if the current wild enemy species exists in that box
+IsEnemyMonSpeciesInPlayerPCBox:
+	ld a, d
+	cp NUM_BOXES / 2
+	ld b, 2
+	jr c, .haveBank
+	ld b, 3
+	sub NUM_BOXES / 2
+.haveBank
+	ld e, a
+	ld d, 0
+	ld hl, BattleBoxSRAMPointerTable
+	add hl, de
+	add hl, de
+	ld a, [hli]
+	ld h, [hl]
+	ld l, a
+	call EnableEncounterCatchSRAM_Battle
+	ld a, b
+	ld [rRAMB], a
+	ld a, [hl]
+	ld c, a
+	inc hl
+	ld a, c
+	cp MONS_PER_BOX + 1
+	jr c, .scanSpeciesLoop
+	ld c, MONS_PER_BOX
+.scanSpeciesLoop
+	ld a, c
+	and a
+	jr z, .notInBox
+	ld a, [hli]
+	cp -1
+	jr z, .notInBox
+	ld b, a
+	ld a, [wEnemyMonSpecies]
+	cp b
+	jr z, .inBox
+	dec c
+	jr .scanSpeciesLoop
+.inBox
+	call DisableEncounterCatchSRAM_Battle
+	ld a, 1
+	ret
+.notInBox
+	call DisableEncounterCatchSRAM_Battle
+	xor a
+	ret
+
+BattleBoxSRAMPointerTable:
+	dw sBox1 ; sBox7
+	dw sBox2 ; sBox8
+	dw sBox3 ; sBox9
+	dw sBox4 ; sBox10
+	dw sBox5 ; sBox11
+	dw sBox6 ; sBox12
 
 ; asks if you want to use next mon
 ; stores whether you ran in C flag
diff --git a/engine/events/poison.asm b/engine/events/poison.asm
index 9d87b3ca..f3c66345 100644
--- a/engine/events/poison.asm
+++ b/engine/events/poison.asm
@@ -68,7 +68,9 @@ ApplyOutOfBattlePoisonDamage:
 	callfar PlayPikachuSoundClip
 	callfar_ModifyPikachuHappiness PIKAHAPPY_PSNFNT
 .curMonNotPlayerPikachu
-	call HandlePoisonFaintedMonRanAway
+	ld a, [wWhichPokemon]
+	ld [wPlayerMonNumber], a
+	callfar HandleFaintedPlayerMonRanAway
 	pop de
 	pop hl
 	jr .restartAfterRemoval
@@ -148,34 +150,6 @@ ApplyOutOfBattlePoisonDamage:
 	ld [wOutOfBattleBlackout], a
 	ret
 
-PoisonFaintedMonRanAwayText:
-	text_far _PokemonRanAwayBadTrainingText
-	text_end
-
-HandlePoisonFaintedMonRanAway:
-	ld a, [wPartyCount]
-	cp 1
-	ret z ; don't remove the final party mon to avoid invalid 0-mon party state
-	ld hl, wPartyMonNicks
-	call GetPartyMonName
-	ld hl, PoisonFaintedMonRanAwayText
-	call PrintText
-	xor a
-	ld [wRemoveMonFromBox], a
-	call RemovePokemon
-	ld a, [wPartyCount]
-	and a
-	ret z
-	dec a
-	ld b, a
-	ld a, [wWhichPokemon]
-	cp b
-	jr c, .done
-	ld a, b
-	ld [wWhichPokemon], a
-.done
-	ret
-
 Func_c4c7:
 	ld a, [wStepCounter]
 	and a

From 8560a58b73260507bc3f6ec0a9bc2684a3d201d8 Mon Sep 17 00:00:00 2001
From: robjlyons <81177492+robjlyons@users.noreply.github.com>
Date: Wed, 11 Feb 2026 12:41:06 +0000
Subject: [PATCH 05/12] Update core.asm

---
 engine/battle/core.asm | 32 --------------------------------
 1 file changed, 32 deletions(-)

diff --git a/engine/battle/core.asm b/engine/battle/core.asm
index 74756bc1..135c2cd2 100644
--- a/engine/battle/core.asm
+++ b/engine/battle/core.asm
@@ -1324,38 +1324,6 @@ BattleBoxSRAMPointerTable:
 	dw sBox5 ; sBox11
 	dw sBox6 ; sBox12
 
-; Returns non-zero if the current wild enemy species is in the player's party or PC boxes.
-IsEnemyMonSpeciesInPlayerCollection:
-	call IsEnemyMonSpeciesInPlayerParty
-	and a
-	ret nz
-	call IsEnemyMonSpeciesInAnyPlayerPCBox
-	and a
-	ret
-
-; Returns non-zero if the current wild enemy species is already present in the player's party.
-IsEnemyMonSpeciesInPlayerParty:
-	ld a, [wPartyCount]
-	ld c, a
-	ld hl, wPartySpecies
-.loop
-	ld a, c
-	and a
-	jr z, .notInParty
-	ld a, [hli]
-	ld b, a
-	ld a, [wEnemyMonSpecies]
-	cp b
-	jr z, .inParty
-	dec c
-	jr .loop
-.inParty
-	ld a, 1
-	ret
-.notInParty
-	xor a
-	ret
-
 ; Returns non-zero if the current wild enemy species is present in any of the player's PC boxes.
 IsEnemyMonSpeciesInAnyPlayerPCBox:
 	ld d, 0

From 7190a7e0c7e67f30bf0ec10417e14e1957927689 Mon Sep 17 00:00:00 2001
From: robjlyons <81177492+robjlyons@users.noreply.github.com>
Date: Wed, 11 Feb 2026 12:43:30 +0000
Subject: [PATCH 06/12] Remove enemy species check from PC boxes

Removed functions that check if the current wild enemy species is present in the player's PC boxes.
---
 engine/battle/core.asm | 74 ------------------------------------------
 1 file changed, 74 deletions(-)

diff --git a/engine/battle/core.asm b/engine/battle/core.asm
index 135c2cd2..306117a6 100644
--- a/engine/battle/core.asm
+++ b/engine/battle/core.asm
@@ -1324,80 +1324,6 @@ BattleBoxSRAMPointerTable:
 	dw sBox5 ; sBox11
 	dw sBox6 ; sBox12
 
-; Returns non-zero if the current wild enemy species is present in any of the player's PC boxes.
-IsEnemyMonSpeciesInAnyPlayerPCBox:
-	ld d, 0
-.boxLoop
-	ld a, d
-	cp NUM_BOXES
-	jr z, .notInPC
-	push de
-	call IsEnemyMonSpeciesInPlayerPCBox
-	pop de
-	and a
-	jr nz, .inPC
-	inc d
-	jr .boxLoop
-.inPC
-	ld a, 1
-	ret
-.notInPC
-	xor a
-	ret
-
-; Checks one PC box.
-; in: d = box index (0 to NUM_BOXES - 1)
-; out: non-zero if the current wild enemy species exists in that box
-IsEnemyMonSpeciesInPlayerPCBox:
-	ld a, d
-	cp NUM_BOXES / 2
-	ld b, 2
-	jr c, .haveBank
-	ld b, 3
-	sub NUM_BOXES / 2
-.haveBank
-	ld e, a
-	ld d, 0
-	ld hl, BattleBoxSRAMPointerTable
-	add hl, de
-	add hl, de
-	ld a, [hli]
-	ld h, [hl]
-	ld l, a
-	call EnableSRAM
-	ld a, b
-	ld [rRAMB], a
-	ld a, [hl]
-	ld c, a
-	inc hl
-.scanSpeciesLoop
-	ld a, c
-	and a
-	jr z, .notInBox
-	ld a, [hli]
-	ld b, a
-	ld a, [wEnemyMonSpecies]
-	cp b
-	jr z, .inBox
-	dec c
-	jr .scanSpeciesLoop
-.inBox
-	call DisableSRAM
-	ld a, 1
-	ret
-.notInBox
-	call DisableSRAM
-	xor a
-	ret
-
-BattleBoxSRAMPointerTable:
-	dw sBox1 ; sBox7
-	dw sBox2 ; sBox8
-	dw sBox3 ; sBox9
-	dw sBox4 ; sBox10
-	dw sBox5 ; sBox11
-	dw sBox6 ; sBox12
-
 ; asks if you want to use next mon
 ; stores whether you ran in C flag
 DoUseNextMonDialogue:

From 9742b7126ae229799778a1696f64074810730f65 Mon Sep 17 00:00:00 2001
From: robjlyons <81177492+robjlyons@users.noreply.github.com>
Date: Wed, 11 Feb 2026 13:18:46 +0000
Subject: [PATCH 07/12] Use home SRAM API for battle PC box scanning

---
 engine/battle/core.asm   | 129 ++++++++++++++++++++++++++++++++++++---
 engine/events/poison.asm |  32 +---------
 2 files changed, 122 insertions(+), 39 deletions(-)

diff --git a/engine/battle/core.asm b/engine/battle/core.asm
index f13ed4b7..c9b1365e 100644
--- a/engine/battle/core.asm
+++ b/engine/battle/core.asm
@@ -170,6 +170,9 @@ StartBattle:
 	ld a, c
 	and a
 	jr z, .skipWildCatchInit
+	call IsEnemyMonSpeciesInPlayerCollection
+	and a
+	jr nz, .skipWildCatchInit
 	ld a, 1
 	ld [wWildEncounterCanCatch], a
 .skipWildCatchInit
@@ -1194,18 +1197,124 @@ EnsureEncounterCatchFlagsInitialized:
 	ret
 
 EnableEncounterCatchSRAM_Battle:
-    ld a, $0A
-    ld [$0000], a                 ; enable SRAM
-    ld a, $01
-    ld [$6000], a                 ; MBC1: RAM banking mode (harmless on others)
-    ld a, BANK(sMapEncounterCatchFlags)
-    ld [$4000], a                 ; select SRAM bank that holds the flags
-    ret
+	ld a, BANK(sMapEncounterCatchFlags)
+	call OpenSRAM
+	ret
 
 DisableEncounterCatchSRAM_Battle:
-    xor a
-    ld [$0000], a                 ; disable SRAM
-    ret
+	call CloseSRAM
+	ret
+
+; Returns non-zero if the current wild enemy species is in the player's party or PC boxes.
+IsEnemyMonSpeciesInPlayerCollection:
+	call IsEnemyMonSpeciesInPlayerParty
+	and a
+	ret nz
+	call IsEnemyMonSpeciesInAnyPlayerPCBox
+	and a
+	ret
+
+; Returns non-zero if the current wild enemy species is already present in the player's party.
+IsEnemyMonSpeciesInPlayerParty:
+	ld a, [wPartyCount]
+	ld c, a
+	ld hl, wPartySpecies
+.loop
+	ld a, c
+	and a
+	jr z, .notInParty
+	ld a, [hli]
+	ld b, a
+	ld a, [wEnemyMonSpecies]
+	cp b
+	jr z, .inParty
+	dec c
+	jr .loop
+.inParty
+	ld a, 1
+	ret
+.notInParty
+	xor a
+	ret
+
+; Returns non-zero if the current wild enemy species is present in any of the player's PC boxes.
+IsEnemyMonSpeciesInAnyPlayerPCBox:
+	ld d, 0
+.boxLoop
+	ld a, d
+	cp NUM_BOXES
+	jr z, .notInPC
+	push de
+	call IsEnemyMonSpeciesInPlayerPCBox
+	pop de
+	and a
+	jr nz, .inPC
+	inc d
+	jr .boxLoop
+.inPC
+	ld a, 1
+	ret
+.notInPC
+	xor a
+	ret
+
+; Checks one PC box.
+; in: d = box index (0 to NUM_BOXES - 1)
+; out: non-zero if the current wild enemy species exists in that box
+IsEnemyMonSpeciesInPlayerPCBox:
+	ld a, d
+	cp NUM_BOXES / 2
+	ld b, 2
+	jr c, .haveBank
+	ld b, 3
+	sub NUM_BOXES / 2
+.haveBank
+	ld e, a
+	ld d, 0
+	ld hl, BattleBoxSRAMPointerTable
+	add hl, de
+	add hl, de
+	ld a, [hli]
+	ld h, [hl]
+	ld l, a
+	ld a, b
+	call OpenSRAM
+	ld a, [hl]
+	ld c, a
+	inc hl
+	ld a, c
+	cp MONS_PER_BOX + 1
+	jr c, .scanSpeciesLoop
+	ld c, MONS_PER_BOX
+.scanSpeciesLoop
+	ld a, c
+	and a
+	jr z, .notInBox
+	ld a, [hli]
+	cp -1
+	jr z, .notInBox
+	ld b, a
+	ld a, [wEnemyMonSpecies]
+	cp b
+	jr z, .inBox
+	dec c
+	jr .scanSpeciesLoop
+.inBox
+	call CloseSRAM
+	ld a, 1
+	ret
+.notInBox
+	call CloseSRAM
+	xor a
+	ret
+
+BattleBoxSRAMPointerTable:
+	dw sBox1 ; sBox7
+	dw sBox2 ; sBox8
+	dw sBox3 ; sBox9
+	dw sBox4 ; sBox10
+	dw sBox5 ; sBox11
+	dw sBox6 ; sBox12
 
 ; asks if you want to use next mon
 ; stores whether you ran in C flag
diff --git a/engine/events/poison.asm b/engine/events/poison.asm
index 9d87b3ca..f3c66345 100644
--- a/engine/events/poison.asm
+++ b/engine/events/poison.asm
@@ -68,7 +68,9 @@ ApplyOutOfBattlePoisonDamage:
 	callfar PlayPikachuSoundClip
 	callfar_ModifyPikachuHappiness PIKAHAPPY_PSNFNT
 .curMonNotPlayerPikachu
-	call HandlePoisonFaintedMonRanAway
+	ld a, [wWhichPokemon]
+	ld [wPlayerMonNumber], a
+	callfar HandleFaintedPlayerMonRanAway
 	pop de
 	pop hl
 	jr .restartAfterRemoval
@@ -148,34 +150,6 @@ ApplyOutOfBattlePoisonDamage:
 	ld [wOutOfBattleBlackout], a
 	ret
 
-PoisonFaintedMonRanAwayText:
-	text_far _PokemonRanAwayBadTrainingText
-	text_end
-
-HandlePoisonFaintedMonRanAway:
-	ld a, [wPartyCount]
-	cp 1
-	ret z ; don't remove the final party mon to avoid invalid 0-mon party state
-	ld hl, wPartyMonNicks
-	call GetPartyMonName
-	ld hl, PoisonFaintedMonRanAwayText
-	call PrintText
-	xor a
-	ld [wRemoveMonFromBox], a
-	call RemovePokemon
-	ld a, [wPartyCount]
-	and a
-	ret z
-	dec a
-	ld b, a
-	ld a, [wWhichPokemon]
-	cp b
-	jr c, .done
-	ld a, b
-	ld [wWhichPokemon], a
-.done
-	ret
-
 Func_c4c7:
 	ld a, [wStepCounter]
 	and a

From 50941f22115b6f9e1eed710e2252b72cde4711a0 Mon Sep 17 00:00:00 2001
From: robjlyons <81177492+robjlyons@users.noreply.github.com>
Date: Wed, 11 Feb 2026 14:00:04 +0000
Subject: [PATCH 08/12] Update core.asm

---
 engine/battle/core.asm | 11 ++---------
 1 file changed, 2 insertions(+), 9 deletions(-)

diff --git a/engine/battle/core.asm b/engine/battle/core.asm
index 306117a6..592c5613 100644
--- a/engine/battle/core.asm
+++ b/engine/battle/core.asm
@@ -1197,19 +1197,12 @@ EnsureEncounterCatchFlagsInitialized:
 	ret
 
 EnableEncounterCatchSRAM_Battle:
-	ld a, BMODE_ADVANCED
-	ld [rBMODE], a
-	ld a, RAMG_SRAM_ENABLE
-	ld [rRAMG], a
 	ld a, BANK(sMapEncounterCatchFlags)
-	ld [rRAMB], a
+	call OpenSRAM
 	ret
 
 DisableEncounterCatchSRAM_Battle:
-	ld a, BMODE_SIMPLE ; preserve flags
-	ld [rBMODE], a
-	ASSERT RAMG_SRAM_DISABLE == BMODE_SIMPLE
-	ld [rRAMG], a
+	call CloseSRAM
 	ret
 
 ; Returns non-zero if the current wild enemy species is in the player's party or PC boxes.

From 04be5b621c5c6e23212ba5350d6db1e32a85e974 Mon Sep 17 00:00:00 2001
From: robjlyons <81177492+robjlyons@users.noreply.github.com>
Date: Wed, 11 Feb 2026 14:13:19 +0000
Subject: [PATCH 09/12] Update core.asm

---
 engine/battle/core.asm | 102 ++++++++++++++++++++++++-----------------
 1 file changed, 60 insertions(+), 42 deletions(-)

diff --git a/engine/battle/core.asm b/engine/battle/core.asm
index 592c5613..b9c958bc 100644
--- a/engine/battle/core.asm
+++ b/engine/battle/core.asm
@@ -1262,52 +1262,70 @@ IsEnemyMonSpeciesInAnyPlayerPCBox:
 ; in: d = box index (0 to NUM_BOXES - 1)
 ; out: non-zero if the current wild enemy species exists in that box
 IsEnemyMonSpeciesInPlayerPCBox:
-	ld a, d
-	cp NUM_BOXES / 2
-	ld b, 2
-	jr c, .haveBank
-	ld b, 3
-	sub NUM_BOXES / 2
+    ; input: d = box index (0..NUM_BOXES-1)
+    ; output: a = 1 if found, 0 if not
+    ; clobbers: a,b,c,d,e,hl
+
+    ld a, d
+    cp NUM_BOXES / 2
+    ld b, 2
+    jr c, .haveBank
+    ld b, 3
+    sub NUM_BOXES / 2
 .haveBank
-	ld e, a
-	ld d, 0
-	ld hl, BattleBoxSRAMPointerTable
-	add hl, de
-	add hl, de
-	ld a, [hli]
-	ld h, [hl]
-	ld l, a
-	call EnableEncounterCatchSRAM_Battle
-	ld a, b
-	ld [rRAMB], a
-	ld a, [hl]
-	ld c, a
-	inc hl
-	ld a, c
-	cp MONS_PER_BOX + 1
-	jr c, .scanSpeciesLoop
-	ld c, MONS_PER_BOX
+    ; a now = box index within this SRAM half (0..)
+    ld e, a
+    ld d, 0
+
+    ; hl = BattleBoxSRAMPointerTable[box] (word table)
+    ld hl, BattleBoxSRAMPointerTable
+    add hl, de
+    add hl, de
+    ld a, [hli]
+    ld h, [hl]
+    ld l, a
+
+    ; --- open SRAM bank b safely ---
+    ld a, b
+    call OpenSRAM
+
+    ; first byte is box count
+    ld a, [hl]
+    ld c, a
+    inc hl
+
+    ; clamp count to MONS_PER_BOX
+    ld a, c
+    cp MONS_PER_BOX + 1
+    jr c, .scanSpeciesLoop
+    ld c, MONS_PER_BOX
+
 .scanSpeciesLoop
-	ld a, c
-	and a
-	jr z, .notInBox
-	ld a, [hli]
-	cp -1
-	jr z, .notInBox
-	ld b, a
-	ld a, [wEnemyMonSpecies]
-	cp b
-	jr z, .inBox
-	dec c
-	jr .scanSpeciesLoop
+    ld a, c
+    and a
+    jr z, .notInBox
+
+    ld a, [hli]
+    cp -1
+    jr z, .notInBox
+
+    ld b, a
+    ld a, [wEnemyMonSpecies]
+    cp b
+    jr z, .inBox
+
+    dec c
+    jr .scanSpeciesLoop
+
 .inBox
-	call DisableEncounterCatchSRAM_Battle
-	ld a, 1
-	ret
+    call CloseSRAM
+    ld a, 1
+    ret
+
 .notInBox
-	call DisableEncounterCatchSRAM_Battle
-	xor a
-	ret
+    call CloseSRAM
+    xor a
+    ret
 
 BattleBoxSRAMPointerTable:
 	dw sBox1 ; sBox7

From ee17b3a8cff7f253b906c00ff3bcd392ef1d8170 Mon Sep 17 00:00:00 2001
From: robjlyons <81177492+robjlyons@users.noreply.github.com>
Date: Wed, 11 Feb 2026 14:29:51 +0000
Subject: [PATCH 10/12] Update core.asm

---
 engine/battle/core.asm | 32 +++++++++++++++-----------------
 1 file changed, 15 insertions(+), 17 deletions(-)

diff --git a/engine/battle/core.asm b/engine/battle/core.asm
index b9c958bc..14a74af4 100644
--- a/engine/battle/core.asm
+++ b/engine/battle/core.asm
@@ -1197,13 +1197,13 @@ EnsureEncounterCatchFlagsInitialized:
 	ret
 
 EnableEncounterCatchSRAM_Battle:
-	ld a, BANK(sMapEncounterCatchFlags)
-	call OpenSRAM
-	ret
+    ld a, BANK(sMapEncounterCatchFlags) ; should be 0 now
+    call OpenSRAM
+    ret
 
 DisableEncounterCatchSRAM_Battle:
-	call CloseSRAM
-	ret
+    call CloseSRAM
+    ret
 
 ; Returns non-zero if the current wild enemy species is in the player's party or PC boxes.
 IsEnemyMonSpeciesInPlayerCollection:
@@ -1245,7 +1245,7 @@ IsEnemyMonSpeciesInAnyPlayerPCBox:
 	cp NUM_BOXES
 	jr z, .notInPC
 	push de
-	call IsEnemyMonSpeciesInPlayerPCBox
+	call 
 	pop de
 	and a
 	jr nz, .inPC
@@ -1262,9 +1262,8 @@ IsEnemyMonSpeciesInAnyPlayerPCBox:
 ; in: d = box index (0 to NUM_BOXES - 1)
 ; out: non-zero if the current wild enemy species exists in that box
 IsEnemyMonSpeciesInPlayerPCBox:
-    ; input: d = box index (0..NUM_BOXES-1)
-    ; output: a = 1 if found, 0 if not
-    ; clobbers: a,b,c,d,e,hl
+    ; in:  d = box index (0..NUM_BOXES-1)
+    ; out: a = 1 if found, 0 if not
 
     ld a, d
     cp NUM_BOXES / 2
@@ -1273,11 +1272,10 @@ IsEnemyMonSpeciesInPlayerPCBox:
     ld b, 3
     sub NUM_BOXES / 2
 .haveBank
-    ; a now = box index within this SRAM half (0..)
+    ; a = index within half (0..5)
     ld e, a
     ld d, 0
 
-    ; hl = BattleBoxSRAMPointerTable[box] (word table)
     ld hl, BattleBoxSRAMPointerTable
     add hl, de
     add hl, de
@@ -1285,22 +1283,22 @@ IsEnemyMonSpeciesInPlayerPCBox:
     ld h, [hl]
     ld l, a
 
-    ; --- open SRAM bank b safely ---
+    ; --- Open SRAM bank b safely ---
     ld a, b
     call OpenSRAM
 
-    ; first byte is box count
+    ; box count
     ld a, [hl]
     ld c, a
     inc hl
 
-    ; clamp count to MONS_PER_BOX
+    ; clamp
     ld a, c
     cp MONS_PER_BOX + 1
-    jr c, .scanSpeciesLoop
+    jr c, .scan
     ld c, MONS_PER_BOX
 
-.scanSpeciesLoop
+.scan
     ld a, c
     and a
     jr z, .notInBox
@@ -1315,7 +1313,7 @@ IsEnemyMonSpeciesInPlayerPCBox:
     jr z, .inBox
 
     dec c
-    jr .scanSpeciesLoop
+    jr .scan
 
 .inBox
     call CloseSRAM

From 4b6057472a89206390d9534372d375002e787963 Mon Sep 17 00:00:00 2001
From: robjlyons <81177492+robjlyons@users.noreply.github.com>
Date: Wed, 11 Feb 2026 14:30:33 +0000
Subject: [PATCH 11/12] Update item_effects.asm

---
 engine/items/item_effects.asm | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/engine/items/item_effects.asm b/engine/items/item_effects.asm
index 1f6b4d34..37cd2d76 100644
--- a/engine/items/item_effects.asm
+++ b/engine/items/item_effects.asm
@@ -2669,15 +2669,12 @@ MarkWildEncounterCatchUsedItem:
     ret
 
 EnableEncounterCatchSRAM_Item:
-    ld a, $0A
-    ld [$0000], a      ; enable SRAM
-    xor a
-    ld [$4000], a      ; SRAM bank 0
+    ld a, BANK(sMapEncounterCatchFlags) ; should be 0 now
+    call OpenSRAM
     ret
 
 DisableEncounterCatchSRAM_Item:
-    xor a
-    ld [$0000], a      ; disable SRAM
+    call CloseSRAM
     ret
 
 NoCyclingAllowedHereText:

From 0275f2d56e028a89f4b6bdc540016780dc29d2f9 Mon Sep 17 00:00:00 2001
From: robjlyons <81177492+robjlyons@users.noreply.github.com>
Date: Wed, 11 Feb 2026 14:32:51 +0000
Subject: [PATCH 12/12] Update core.asm

---
 engine/battle/core.asm | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/engine/battle/core.asm b/engine/battle/core.asm
index 14a74af4..b5af70ce 100644
--- a/engine/battle/core.asm
+++ b/engine/battle/core.asm
@@ -1245,7 +1245,7 @@ IsEnemyMonSpeciesInAnyPlayerPCBox:
 	cp NUM_BOXES
 	jr z, .notInPC
 	push de
-	call 
+	call IsEnemyMonSpeciesInPlayerPCBox
 	pop de
 	and a
 	jr nz, .inPC