diff --git a/data/battle_scripts_1.s b/data/battle_scripts_1.s
index e47839adfe..c9662b783b 100644
--- a/data/battle_scripts_1.s
+++ b/data/battle_scripts_1.s
@@ -7058,11 +7058,15 @@ BattleScript_CudChewActivates::
 
 BattleScript_TargetFormChangeNoPopup:
 	flushtextbox
-	handleformchange BS_TARGET, 0
-	handleformchange BS_TARGET, 1
+	handleformchange BS_SCRIPTING, 0
+	handleformchange BS_SCRIPTING, 1
 	playanimation BS_TARGET, B_ANIM_FORM_CHANGE
 	waitanimation
-	handleformchange BS_TARGET, 2
+	handleformchange BS_SCRIPTING, 2
+.if B_DISGUISE_HP_LOSS >= GEN_8
+	healthbarupdate BS_SCRIPTING
+	datahpupdate BS_SCRIPTING
+.endif
 	return
 
 BattleScript_TargetFormChange::
diff --git a/include/battle_script_commands.h b/include/battle_script_commands.h
index d77ddfdfbc..540390bb53 100644
--- a/include/battle_script_commands.h
+++ b/include/battle_script_commands.h
@@ -37,7 +37,7 @@ void BufferMoveToLearnIntoBattleTextBuff2(void);
 void HandleBattleWindow(u8 xStart, u8 yStart, u8 xEnd, u8 yEnd, u8 flags);
 bool8 UproarWakeUpCheck(u8 battlerId);
 bool32 DoesSubstituteBlockMove(u32 battlerAtk, u32 battlerDef, u32 move);
-bool32 DoesDisguiseBlockMove(u32 battlerAtk, u32 battlerDef, u32 move);
+bool32 DoesDisguiseBlockMove(u32 battler, u32 move);
 bool32 CanPoisonType(u8 battlerAttacker, u8 battlerTarget);
 bool32 CanParalyzeType(u8 battlerAttacker, u8 battlerTarget);
 bool32 CanUseLastResort(u8 battlerId);
diff --git a/include/config/battle.h b/include/config/battle.h
index ffdfc40385..04d290f664 100644
--- a/include/config/battle.h
+++ b/include/config/battle.h
@@ -143,6 +143,7 @@
 #define B_PROTEAN_LIBERO            GEN_LATEST // In Gen9+, Protean and Libero change the user's type only once per Battle.
 #define B_INTREPID_SWORD            GEN_LATEST // In Gen9+, Intrepid Sword raises Attack by one stage only once per Battle.
 #define B_DAUNTLESS_SHIELD          GEN_LATEST // In Gen9+, Dauntless Shield raises Defense by one stage only once per Battle.
+#define B_DISGUISE_HP_LOSS          GEN_LATEST // In Gen8+, when a Disguised Mimikyu's Disguise is busted, upon changing to its Busted Form it loses HP equal to 1/8 of its maximum HP.
 
 // Item settings
 #define B_HP_BERRIES                GEN_LATEST // In Gen4+, berries which restore HP activate immediately after HP drops to half. In Gen3, the effect occurs at the end of the turn.
diff --git a/src/battle_script_commands.c b/src/battle_script_commands.c
index bbee19244e..2bc25cd786 100644
--- a/src/battle_script_commands.c
+++ b/src/battle_script_commands.c
@@ -2006,7 +2006,7 @@ static void Cmd_adjustdamage(void)
 
     if (DoesSubstituteBlockMove(gBattlerAttacker, gBattlerTarget, gCurrentMove))
         goto END;
-    if (DoesDisguiseBlockMove(gBattlerAttacker, gBattlerTarget, gCurrentMove))
+    if (DoesDisguiseBlockMove(gBattlerTarget, gCurrentMove))
     {
         gBattleStruct->enduredDamage |= gBitTable[gBattlerTarget];
         goto END;
@@ -2258,7 +2258,7 @@ static void Cmd_healthbarupdate(void)
         {
             PrepareStringBattle(STRINGID_SUBSTITUTEDAMAGED, battler);
         }
-        else if (!DoesDisguiseBlockMove(gBattlerAttacker, battler, gCurrentMove))
+        else if (!DoesDisguiseBlockMove(battler, gCurrentMove))
         {
             s16 healthValue = min(gBattleMoveDamage, 10000); // Max damage (10000) not present in R/S, ensures that huge damage values don't change sign
 
@@ -2311,16 +2311,19 @@ static void Cmd_datahpupdate(void)
                 return;
             }
         }
-        else if (DoesDisguiseBlockMove(gBattlerAttacker, battler, gCurrentMove))
+        else if (DoesDisguiseBlockMove(battler, gCurrentMove))
         {
             // TODO: Convert this to a proper FORM_CHANGE type.
             u32 side = GetBattlerSide(battler);
+            gBattleScripting.battler = battler;
             if (gBattleStruct->changedSpecies[side][gBattlerPartyIndexes[battler]] == SPECIES_NONE)
                 gBattleStruct->changedSpecies[side][gBattlerPartyIndexes[battler]] = gBattleMons[battler].species;
             if (gBattleMons[battler].species == SPECIES_MIMIKYU_TOTEM_DISGUISED)
                 gBattleMons[battler].species = SPECIES_MIMIKYU_TOTEM_BUSTED;
             else
                 gBattleMons[battler].species = SPECIES_MIMIKYU_BUSTED;
+            if (B_DISGUISE_HP_LOSS >= GEN_8)
+                gBattleMoveDamage = GetNonDynamaxMaxHP(battler) / 8;
             BattleScriptPush(cmd->nextInstr);
             gBattlescriptCurrInstr = BattleScript_TargetFormChange;
             return;
@@ -14736,13 +14739,13 @@ bool32 DoesSubstituteBlockMove(u32 battlerAtk, u32 battlerDef, u32 move)
         return TRUE;
 }
 
-bool32 DoesDisguiseBlockMove(u32 battlerAtk, u32 battlerDef, u32 move)
+bool32 DoesDisguiseBlockMove(u32 battler, u32 move)
 {
-    if (!(gBattleMons[battlerDef].species == SPECIES_MIMIKYU_DISGUISED || gBattleMons[battlerDef].species == SPECIES_MIMIKYU_TOTEM_DISGUISED)
-        || gBattleMons[battlerDef].status2 & STATUS2_TRANSFORMED
-        || IS_MOVE_STATUS(move)
+    if (!(gBattleMons[battler].species == SPECIES_MIMIKYU_DISGUISED || gBattleMons[battler].species == SPECIES_MIMIKYU_TOTEM_DISGUISED)
+        || gBattleMons[battler].status2 & STATUS2_TRANSFORMED
+        || (!gProtectStructs[battler].confusionSelfDmg && (IS_MOVE_STATUS(move) || gHitMarker & HITMARKER_PASSIVE_DAMAGE))
         || gHitMarker & HITMARKER_IGNORE_DISGUISE
-        || GetBattlerAbility(battlerDef) != ABILITY_DISGUISE)
+        || GetBattlerAbility(battler) != ABILITY_DISGUISE)
         return FALSE;
     else
         return TRUE;
diff --git a/src/data/moves_info.h b/src/data/moves_info.h
index b4639fd290..f23f664ea5 100644
--- a/src/data/moves_info.h
+++ b/src/data/moves_info.h
@@ -20231,6 +20231,7 @@ const struct MoveInfo gMovesInfo[MOVES_COUNT_DYNAMAX] =
         .target = MOVE_TARGET_SELECTED,
         .priority = 0,
         .category = DAMAGE_CATEGORY_PHYSICAL,
+        .ignoresTargetAbility = TRUE,
     },
     [MOVE_MENACING_MOONRAZE_MAELSTROM] =
     {
@@ -20244,6 +20245,7 @@ const struct MoveInfo gMovesInfo[MOVES_COUNT_DYNAMAX] =
         .target = MOVE_TARGET_SELECTED,
         .priority = 0,
         .category = DAMAGE_CATEGORY_SPECIAL,
+        .ignoresTargetAbility = TRUE,
     },
     [MOVE_LIGHT_THAT_BURNS_THE_SKY] =
     {
@@ -20257,6 +20259,7 @@ const struct MoveInfo gMovesInfo[MOVES_COUNT_DYNAMAX] =
         .target = MOVE_TARGET_SELECTED,
         .priority = 0,
         .category = DAMAGE_CATEGORY_SPECIAL,
+        .ignoresTargetAbility = TRUE,
     },
     [MOVE_SOUL_STEALING_7_STAR_STRIKE] =
     {
diff --git a/test/battle/ability/disguise.c b/test/battle/ability/disguise.c
new file mode 100644
index 0000000000..7d3e36bf78
--- /dev/null
+++ b/test/battle/ability/disguise.c
@@ -0,0 +1,123 @@
+#include "global.h"
+#include "test/battle.h"
+
+ASSUMPTIONS
+{
+    ASSUME(gMovesInfo[MOVE_AERIAL_ACE].category == DAMAGE_CATEGORY_PHYSICAL);
+}
+
+SINGLE_BATTLE_TEST("Disguised Mimikyu will lose 1/8 of its max HP upon changing to its busted form")
+{
+    s16 disguiseDamage;
+
+    GIVEN {
+        PLAYER(SPECIES_MIMIKYU_DISGUISED) { Ability(ABILITY_DISGUISE); }
+        OPPONENT(SPECIES_WOBBUFFET);
+    } WHEN {
+        TURN { MOVE(opponent, MOVE_AERIAL_ACE); }
+    } SCENE {
+        ANIMATION(ANIM_TYPE_MOVE, MOVE_AERIAL_ACE, opponent);
+        ABILITY_POPUP(player, ABILITY_DISGUISE);
+        HP_BAR(player, captureDamage: &disguiseDamage);
+    } THEN {
+        EXPECT_EQ(player->species, SPECIES_MIMIKYU_BUSTED);
+        EXPECT_EQ(disguiseDamage, player->maxHP / 8);
+    }
+}
+
+SINGLE_BATTLE_TEST("Disguised Mimikyu takes no damage from a confusion hit and changes to its busted form")
+{
+    GIVEN {
+        ASSUME(gMovesInfo[MOVE_CONFUSE_RAY].effect == EFFECT_CONFUSE);
+        PLAYER(SPECIES_MIMIKYU_DISGUISED) { Ability(ABILITY_DISGUISE); }
+        OPPONENT(SPECIES_WOBBUFFET);
+    } WHEN {
+        TURN { MOVE(opponent, MOVE_CONFUSE_RAY); }
+        TURN { }
+    } SCENE {
+        ANIMATION(ANIM_TYPE_MOVE, MOVE_CONFUSE_RAY, opponent);
+        ANIMATION(ANIM_TYPE_STATUS, B_ANIM_STATUS_CONFUSION, player);
+        MESSAGE("Mimikyu became confused!");
+        MESSAGE("Mimikyu is confused!");
+        MESSAGE("It hurt itself in its confusion!");
+        NOT HP_BAR(player);
+        ABILITY_POPUP(player, ABILITY_DISGUISE);
+    } THEN {
+        EXPECT_EQ(player->species, SPECIES_MIMIKYU_BUSTED);
+    }
+}
+
+SINGLE_BATTLE_TEST("Disguised Mimikyu's Air Balloon will pop upon changing to its busted form")
+{
+    GIVEN {
+        ASSUME(gItemsInfo[ITEM_AIR_BALLOON].holdEffect == HOLD_EFFECT_AIR_BALLOON);
+        PLAYER(SPECIES_MIMIKYU_DISGUISED) { Ability(ABILITY_DISGUISE); Item(ITEM_AIR_BALLOON); }
+        OPPONENT(SPECIES_WOBBUFFET);
+    } WHEN {
+        TURN { MOVE(opponent, MOVE_AERIAL_ACE); }
+    } SCENE {
+        MESSAGE("Mimikyu floats in the air with its Air Balloon!");
+        ANIMATION(ANIM_TYPE_MOVE, MOVE_AERIAL_ACE, opponent);
+        NOT HP_BAR(player);
+        ABILITY_POPUP(player, ABILITY_DISGUISE);
+        MESSAGE("Mimikyu's Air Balloon popped!");
+    } THEN {
+        EXPECT_EQ(player->species, SPECIES_MIMIKYU_BUSTED);
+    }
+}
+
+SINGLE_BATTLE_TEST("Disguised Mimikyu takes damage from secondary damage without breaking the disguise")
+{
+    GIVEN {
+        ASSUME(gMovesInfo[MOVE_STEALTH_ROCK].effect == EFFECT_STEALTH_ROCK);
+        PLAYER(SPECIES_WOBBUFFET);
+        PLAYER(SPECIES_MIMIKYU_DISGUISED) { Ability(ABILITY_DISGUISE); }
+        OPPONENT(SPECIES_WOBBUFFET);
+    } WHEN {
+        TURN { MOVE(opponent, MOVE_STEALTH_ROCK); }
+        TURN { SWITCH(player, 1); }
+    } SCENE {
+        ANIMATION(ANIM_TYPE_MOVE, MOVE_STEALTH_ROCK, opponent);
+        HP_BAR(player);
+        MESSAGE("Pointed stones dug into Mimikyu!");
+    } THEN {
+        EXPECT_EQ(player->species, SPECIES_MIMIKYU_DISGUISED);
+    }
+}
+
+SINGLE_BATTLE_TEST("Disguised Mimikyu takes damage from Rocky Helmet without breaking the disguise")
+{
+    GIVEN {
+        ASSUME(gItemsInfo[ITEM_ROCKY_HELMET].holdEffect == HOLD_EFFECT_ROCKY_HELMET);
+        PLAYER(SPECIES_MIMIKYU_DISGUISED) { Ability(ABILITY_DISGUISE); }
+        OPPONENT(SPECIES_WOBBUFFET) { Item(ITEM_ROCKY_HELMET); }
+    } WHEN {
+        TURN { MOVE(player, MOVE_AERIAL_ACE); }
+    } SCENE {
+        ANIMATION(ANIM_TYPE_MOVE, MOVE_AERIAL_ACE, player);
+        HP_BAR(opponent);
+        ANIMATION(ANIM_TYPE_GENERAL, B_ANIM_HELD_ITEM_EFFECT, opponent);
+        HP_BAR(player);
+        MESSAGE("Mimikyu was hurt by Foe Wobbuffet's Rocky Helmet!");
+    } THEN {
+        EXPECT_EQ(player->species, SPECIES_MIMIKYU_DISGUISED);
+    }
+}
+
+SINGLE_BATTLE_TEST("Disguised Mimikyu takes damage from Rough Skin without breaking the disguise")
+{
+    GIVEN {
+        PLAYER(SPECIES_MIMIKYU_DISGUISED) { Ability(ABILITY_DISGUISE); }
+        OPPONENT(SPECIES_CARVANHA) { Ability(ABILITY_ROUGH_SKIN); }
+    } WHEN {
+        TURN { MOVE(player, MOVE_AERIAL_ACE); }
+    } SCENE {
+        ANIMATION(ANIM_TYPE_MOVE, MOVE_AERIAL_ACE, player);
+        HP_BAR(opponent);
+        ABILITY_POPUP(opponent, ABILITY_ROUGH_SKIN);
+        HP_BAR(player);
+        MESSAGE("Mimikyu was hurt by Foe Carvanha's Rough Skin!");
+    } THEN {
+        EXPECT_EQ(player->species, SPECIES_MIMIKYU_DISGUISED);
+    }
+}