Boss Dumb Drum

Notes:
 * Rare didn't lie when they named this guy "Dumb Drum." He basically kills himself. You're just the bait. Don't forget what stage you're on and you'll have a good time.
 * Jumping on the first enemy in each sequence as soon as they hit the ground will let you hit the other one on the way up. Army likes to hop backwards before he hits the ground; make sure it doesn't throw you off.