diff --git a/engine/battle/core.asm b/engine/battle/core.asm
index 62813eb4..44c657ee 100644
--- a/engine/battle/core.asm
+++ b/engine/battle/core.asm
@@ -5144,12 +5144,13 @@ MetronomePickMove:
 ; values for enemy turn
 	ld de, wEnemyMoveNum
 	ld hl, wEnemySelectedMove
-; loop to pick a random number in the range [1, $a5) to be the move used by Metronome
+; loop to pick a random number in the range of valid moves used by Metronome
 .pickMoveLoop
 	call BattleRandom
 	and a
 	jr z, .pickMoveLoop
-	cp NUM_ATTACKS ; max move number (including Struggle)
+	cp STRUGGLE
+	assert NUM_ATTACKS == STRUGGLE ; random numbers greater than STRUGGLE are not moves
 	jr nc, .pickMoveLoop
 	cp METRONOME
 	jr z, .pickMoveLoop