diff --git a/data/battle_scripts_1.s b/data/battle_scripts_1.s
index 6e667ebfe9..d85b8cff89 100644
--- a/data/battle_scripts_1.s
+++ b/data/battle_scripts_1.s
@@ -370,6 +370,63 @@ gBattleScriptsForMoveEffects:: @ 82D86A8
 	.4byte BattleScript_EffectAttackerDefenseDownHit
 	.4byte BattleScript_EffectBodyPress
 	.4byte BattleScript_EffectExpandingForce
+	.4byte BattleScript_EffectScaleShot
+
+BattleScript_EffectScaleShot::
+	attackcanceler
+	accuracycheck BattleScript_PrintMoveMissed, ACC_CURR_MOVE
+	attackstring
+	ppreduce
+	setmultihitcounter 0x0
+	initmultihitstring
+	sethword sMULTIHIT_EFFECT, 0x0
+BattleScript_ScaleShotLoop::
+	jumpifhasnohp BS_ATTACKER, BattleScript_ScaleShotEnd
+	jumpifhasnohp BS_TARGET, BattleScript_ScaleShotPrintStrings
+	jumpifhalfword CMP_EQUAL, gChosenMove, MOVE_SLEEP_TALK, BattleScript_ScaleShotDoMultiHit
+	jumpifstatus BS_ATTACKER, STATUS1_SLEEP, BattleScript_ScaleShotPrintStrings
+BattleScript_ScaleShotDoMultiHit::
+	movevaluescleanup
+	copyhword sMOVE_EFFECT, sMULTIHIT_EFFECT
+	critcalc
+	damagecalc
+	jumpifmovehadnoeffect BattleScript_ScaleShotMultiHitNoMoreHits
+	adjustdamage
+	attackanimation
+	waitanimation
+	effectivenesssound
+	hitanimation BS_TARGET
+	waitstate
+	healthbarupdate BS_TARGET
+	datahpupdate BS_TARGET
+	critmessage
+	waitmessage 0x40
+	multihitresultmessage
+	printstring STRINGID_EMPTYSTRING3
+	waitmessage 0x1
+	addbyte sMULTIHIT_STRING + 4, 0x1
+	moveendto MOVEEND_NEXT_TARGET
+	jumpifbyte CMP_COMMON_BITS, gMoveResultFlags, MOVE_RESULT_FOE_ENDURED, BattleScript_ScaleShotPrintStrings
+	decrementmultihit BattleScript_ScaleShotLoop
+	goto BattleScript_ScaleShotPrintStrings
+BattleScript_ScaleShotMultiHitNoMoreHits::
+	pause 0x20
+BattleScript_ScaleShotPrintStrings::
+	resultmessage
+	waitmessage 0x40
+	jumpifmovehadnoeffect BattleScript_ScaleShotEnd
+	copyarray gBattleTextBuff1, sMULTIHIT_STRING, 0x6
+	printstring STRINGID_HITXTIMES
+	waitmessage 0x40
+BattleScript_ScaleShotEnd::
+	setmoveeffect MOVE_EFFECT_SPD_PLUS_1 | MOVE_EFFECT_AFFECTS_USER
+	seteffectwithchance
+	setmoveeffect MOVE_EFFECT_DEF_MINUS_1 | MOVE_EFFECT_AFFECTS_USER
+	seteffectwithchance
+	tryfaintmon BS_TARGET, FALSE, NULL
+	moveendcase MOVEEND_SYNCHRONIZE_TARGET
+	moveendfrom MOVEEND_STATUS_IMMUNITY_ABILITIES
+	end
 
 BattleScript_EffectAttackerDefenseDownHit:
 	setmoveeffect MOVE_EFFECT_DEF_MINUS_1 | MOVE_EFFECT_AFFECTS_USER | MOVE_EFFECT_CERTAIN
diff --git a/include/constants/battle.h b/include/constants/battle.h
index b158076bde..b925904c24 100644
--- a/include/constants/battle.h
+++ b/include/constants/battle.h
@@ -346,7 +346,8 @@
 #define MOVE_EFFECT_THROAT_CHOP         0x43
 #define MOVE_EFFECT_INCINERATE          0x44
 #define MOVE_EFFECT_BUG_BITE            0x45
-#define NUM_MOVE_EFFECTS                0x46
+#define MOVE_EFFECT_SPD_PLUS_1_DEF_MINUS_1 0x46
+#define NUM_MOVE_EFFECTS                0x47
 
 #define MOVE_EFFECT_AFFECTS_USER        0x4000
 #define MOVE_EFFECT_CERTAIN             0x8000
diff --git a/include/constants/battle_move_effects.h b/include/constants/battle_move_effects.h
index cfd4ccdefa..fd26204a15 100644
--- a/include/constants/battle_move_effects.h
+++ b/include/constants/battle_move_effects.h
@@ -354,7 +354,8 @@
 #define EFFECT_ATTACKER_DEFENSE_DOWN_HIT 348
 #define EFFECT_BODY_PRESS 349
 #define EFFECT_EXPANDING_FORCE 350
+#define EFFECT_SCALE_SHOT 351
 
-#define NUM_BATTLE_MOVE_EFFECTS 351
+#define NUM_BATTLE_MOVE_EFFECTS 352
 
 #endif  // GUARD_CONSTANTS_BATTLE_MOVE_EFFECTS_H
diff --git a/src/data/battle_moves.h b/src/data/battle_moves.h
index b556a0a5cf..83ff193a37 100644
--- a/src/data/battle_moves.h
+++ b/src/data/battle_moves.h
@@ -11248,12 +11248,12 @@ const struct BattleMove gBattleMoves[MOVES_COUNT] =
 
     [MOVE_SCALE_SHOT] =
     {
-        .effect = EFFECT_PLACEHOLDER,   //TODO (EFFECT_MULTI_HIT + ABILITY_WEAK_ARMOR,
+        .effect = EFFECT_SCALE_SHOT,
         .power = 25,
         .type = TYPE_DRAGON,
         .accuracy = 90,
         .pp = 20,
-        .secondaryEffectChance = 0,
+        .secondaryEffectChance = 100,
         .target = MOVE_TARGET_SELECTED,
         .priority = 0,
         .flags = FLAG_PROTECT_AFFECTED | FLAG_MIRROR_MOVE_AFFECTED | FLAG_KINGS_ROCK_AFFECTED,