diff --git a/include/constants/battle_ai.h b/include/constants/battle_ai.h
index d48827683a..a7a3e54183 100644
--- a/include/constants/battle_ai.h
+++ b/include/constants/battle_ai.h
@@ -56,6 +56,7 @@
 #define AI_FLAG_STALL                 (1 << 13)  // AI stalls battle and prefers secondary damage/trapping/etc. TODO not finished
 #define AI_FLAG_SCREENER              (1 << 14)  // AI prefers screening effects like reflect, mist, etc. TODO unfinished
 #define AI_FLAG_SMART_SWITCHING       (1 << 15)  // AI includes a lot more switching checks
+#define AI_FLAG_ACE_POKEMON           (1 << 16)  // AI has Ace Pokemon -- Saves until last
 
 // 'other' ai logic flags
 #define AI_FLAG_ROAMING               (1 << 29)
diff --git a/src/battle_ai_switch_items.c b/src/battle_ai_switch_items.c
index 3b00340d27..329d3ebf35 100644
--- a/src/battle_ai_switch_items.c
+++ b/src/battle_ai_switch_items.c
@@ -199,6 +199,10 @@ static bool8 FindMonThatAbsorbsOpponentsMove(void)
             continue;
         if (i == *(gBattleStruct->monToSwitchIntoId + battlerIn2))
             continue;
+        if (AI_THINKING_STRUCT->aiFlags & AI_FLAG_ACE_POKEMON 
+            && i == (CalculateEnemyPartyCount()-1))
+            continue;
+        
 
         species = GetMonData(&party[i], MON_DATA_SPECIES);
         if (GetMonData(&party[i], MON_DATA_ABILITY_NUM) != 0)
@@ -276,6 +280,10 @@ static bool8 ShouldSwitchIfGameStatePrompt(void)
                     
                         for (i = firstId; i < lastId; i++)
                         {
+                            if (AI_THINKING_STRUCT->aiFlags & AI_FLAG_ACE_POKEMON 
+                                && i == (CalculateEnemyPartyCount()-1))
+                                break;
+
                             //Look for mon in party that is able to be switched into and has ability that sets terrain
                             if (GetMonData(&party[i], MON_DATA_HP) != 0
                                 && GetMonData(&party[i], MON_DATA_SPECIES2) != SPECIES_NONE
@@ -562,6 +570,10 @@ static bool8 FindMonWithFlagsAndSuperEffective(u16 flags, u8 moduloPercent)
             continue;
         if (i == *(gBattleStruct->monToSwitchIntoId + battlerIn2))
             continue;
+        if (AI_THINKING_STRUCT->aiFlags & AI_FLAG_ACE_POKEMON 
+            && i == (CalculateEnemyPartyCount()-1))
+            continue;
+
 
         species = GetMonData(&party[i], MON_DATA_SPECIES);
         if (GetMonData(&party[i], MON_DATA_ABILITY_NUM) != 0)
@@ -650,6 +662,9 @@ bool32 ShouldSwitch(void)
             continue;
         if (i == *(gBattleStruct->monToSwitchIntoId + battlerIn2))
             continue;
+        if (AI_THINKING_STRUCT->aiFlags & AI_FLAG_ACE_POKEMON
+            && i == (CalculateEnemyPartyCount()-1))
+            continue;
 
         availableToSwitch++;
     }
@@ -712,7 +727,7 @@ void AI_TrySwitchOrUseItem(void)
 
                     GetAIPartyIndexes(gActiveBattler, &firstId, &lastId);
 
-                    for (monToSwitchId = firstId; monToSwitchId < lastId; monToSwitchId++)
+                    for (monToSwitchId = (lastId-1); monToSwitchId >= firstId; monToSwitchId--)
                     {
                         if (GetMonData(&party[monToSwitchId], MON_DATA_HP) == 0)
                             continue;
@@ -724,6 +739,9 @@ void AI_TrySwitchOrUseItem(void)
                             continue;
                         if (monToSwitchId == *(gBattleStruct->monToSwitchIntoId + battlerIn2))
                             continue;
+                        if (AI_THINKING_STRUCT->aiFlags & AI_FLAG_ACE_POKEMON 
+                            && monToSwitchId == (CalculateEnemyPartyCount()-1))
+                            continue;
 
                         break;
                     }
@@ -921,7 +939,9 @@ u8 GetMostSuitableMonToSwitchInto(void)
             || gBattlerPartyIndexes[battlerIn2] == i
             || i == *(gBattleStruct->monToSwitchIntoId + battlerIn1)
             || i == *(gBattleStruct->monToSwitchIntoId + battlerIn2)
-            || (GetMonAbility(&party[i]) == ABILITY_TRUANT && IsTruantMonVulnerable(gActiveBattler, opposingBattler))) // While not really invalid per say, not really wise to switch into this mon.
+            || (GetMonAbility(&party[i]) == ABILITY_TRUANT && IsTruantMonVulnerable(gActiveBattler, opposingBattler)) // While not really invalid per say, not really wise to switch into this mon.
+            || (AI_THINKING_STRUCT->aiFlags & AI_FLAG_ACE_POKEMON 
+                && i == (CalculateEnemyPartyCount()-1))) //Save Ace Pokemon for last
             invalidMons |= gBitTable[i];
         else
             aliveCount++;
diff --git a/src/battle_controller_opponent.c b/src/battle_controller_opponent.c
index 501e31704c..ddc4c44052 100644
--- a/src/battle_controller_opponent.c
+++ b/src/battle_controller_opponent.c
@@ -2,6 +2,7 @@
 #include "battle.h"
 #include "battle_ai_main.h"
 #include "battle_ai_util.h"
+#include "constants/battle_ai.h"
 #include "battle_anim.h"
 #include "battle_arena.h"
 #include "battle_controllers.h"
@@ -94,6 +95,7 @@ static void OpponentHandleResetActionMoveSelection(void);
 static void OpponentHandleEndLinkBattle(void);
 static void OpponentHandleDebugMenu(void);
 static void OpponentCmdEnd(void);
+static u8 CountAIAliveNonEggMonsExcept(u8 slotToIgnore);
 
 static void OpponentBufferRunCommand(void);
 static void OpponentBufferExecCompleted(void);
@@ -1670,6 +1672,7 @@ static void OpponentHandleChooseItem(void)
 static void OpponentHandleChoosePokemon(void)
 {
     s32 chosenMonId;
+    s32 pokemonInBattle = 1;
 
     if (*(gBattleStruct->AI_monToSwitchIntoId + gActiveBattler) == PARTY_SIZE)
     {
@@ -1687,15 +1690,20 @@ static void OpponentHandleChoosePokemon(void)
             {
                 battler1 = GetBattlerAtPosition(B_POSITION_OPPONENT_LEFT);
                 battler2 = GetBattlerAtPosition(B_POSITION_OPPONENT_RIGHT);
+                pokemonInBattle = 2;
+
             }
 
             GetAIPartyIndexes(gActiveBattler, &firstId, &lastId);
 
-            for (chosenMonId = firstId; chosenMonId < lastId; chosenMonId++)
+            for (chosenMonId = (lastId-1); chosenMonId >= firstId; chosenMonId--)
             {
                 if (GetMonData(&gEnemyParty[chosenMonId], MON_DATA_HP) != 0
                     && chosenMonId != gBattlerPartyIndexes[battler1]
-                    && chosenMonId != gBattlerPartyIndexes[battler2])
+                    && chosenMonId != gBattlerPartyIndexes[battler2]
+                    && (AI_THINKING_STRUCT->aiFlags & AI_FLAG_ACE_POKEMON
+                        && (!(chosenMonId == (CalculateEnemyPartyCount()-1))
+                            || CountAIAliveNonEggMonsExcept(PARTY_SIZE) == pokemonInBattle)))
                 {
                     break;
                 }
@@ -1714,6 +1722,24 @@ static void OpponentHandleChoosePokemon(void)
     OpponentBufferExecCompleted();
 }
 
+static u8 CountAIAliveNonEggMonsExcept(u8 slotToIgnore)
+{
+    u16 i, count;
+
+    for (i = 0, count = 0; i < PARTY_SIZE; i++)
+    {
+        if (i != slotToIgnore
+            && GetMonData(&gEnemyParty[i], MON_DATA_SPECIES) != SPECIES_NONE
+            && !GetMonData(&gEnemyParty[i], MON_DATA_IS_EGG)
+            && GetMonData(&gEnemyParty[i], MON_DATA_HP) != 0)
+        {
+            count++;
+        }
+    }
+
+    return count;
+}
+
 static void OpponentHandleCmd23(void)
 {
     OpponentBufferExecCompleted();