diff --git a/include/battle.h b/include/battle.h
index 35628be83..f19a83e6b 100644
--- a/include/battle.h
+++ b/include/battle.h
@@ -605,6 +605,7 @@ struct BattleStruct
     u8 blunderPolicy:1; // should blunder policy activate
     u8 ballSpriteIds[2];    // item gfx, window gfx
     u8 stickyWebUser;
+    u8 appearedInBattle; // Bitfield to track which Pokemon appeared in battle. Used for Burmy's form change
 };
 
 #define F_DYNAMIC_TYPE_1 (1 << 6)
diff --git a/src/battle_main.c b/src/battle_main.c
index e3169a980..298762ebc 100644
--- a/src/battle_main.c
+++ b/src/battle_main.c
@@ -2991,6 +2991,7 @@ static void BattleStartClearSetData(void)
     gBattleStruct->mega.triggerSpriteId = 0xFF;
     
     gBattleStruct->stickyWebUser = 0xFF;
+    gBattleStruct->appearedInBattle = 0;
     
     for (i = 0; i < PARTY_SIZE; i++)
     {
@@ -3631,6 +3632,9 @@ static void TryDoEventsBeforeFirstTurn(void)
         *(gBattleStruct->monToSwitchIntoId + i) = PARTY_SIZE;
         gChosenActionByBattler[i] = B_ACTION_NONE;
         gChosenMoveByBattler[i] = MOVE_NONE;
+        // Record party slots of player's mons that appeared in battle
+        if (!IsBattlerAIControlled(i))
+            gBattleStruct->appearedInBattle |= gBitTable[gBattlerPartyIndexes[i]];
     }
     TurnValuesCleanUp(FALSE);
     SpecialStatusesClear();
diff --git a/src/battle_script_commands.c b/src/battle_script_commands.c
index b46331be1..175fe6a67 100644
--- a/src/battle_script_commands.c
+++ b/src/battle_script_commands.c
@@ -6187,6 +6187,9 @@ static void Cmd_switchineffects(void)
     gHitMarker &= ~HITMARKER_FAINTED(gActiveBattler);
     gSpecialStatuses[gActiveBattler].faintedHasReplacement = FALSE;
 
+    if (!IsBattlerAIControlled(gActiveBattler))
+        gBattleStruct->appearedInBattle |= gBitTable[gBattlerPartyIndexes[gActiveBattler]];
+
     // Neutralizing Gas announces itself before hazards
     if (gBattleMons[gActiveBattler].ability == ABILITY_NEUTRALIZING_GAS && gSpecialStatuses[gActiveBattler].announceNeutralizingGas == 0)
     {
diff --git a/src/battle_util.c b/src/battle_util.c
index 89fad4b1e..21168b3cd 100644
--- a/src/battle_util.c
+++ b/src/battle_util.c
@@ -9782,13 +9782,13 @@ bool32 TryRoomService(u8 battlerId)
 void DoBurmyFormChange(u32 monId)
 {
     u16 newSpecies, currSpecies;
-    s32 sentIn;
     struct Pokemon *party = gPlayerParty;
 
-    sentIn = gSentPokesToOpponent[(gBattlerFainted & 2) >> 1];
     currSpecies = GetMonData(&party[monId], MON_DATA_SPECIES, NULL);
 
-    if ((GET_BASE_SPECIES_ID(currSpecies) == SPECIES_BURMY) && (gBitTable[monId] & sentIn))
+    if ((GET_BASE_SPECIES_ID(currSpecies) == SPECIES_BURMY) 
+        && (gBattleStruct->appearedInBattle & gBitTable[monId]) // Burmy appeared in battle
+        && GetMonData(&party[monId], MON_DATA_HP, NULL) != 0) // Burmy isn't fainted
     {
         switch (gBattleTerrain)
         {