Skull Kid, Majora's Deviant

Shroud (This creature can't be the target of spells or abilities.)
Melody {b}{r}{g} ({b}{r}{g}, {t}, Untap another tapped creature you control: Draw a card. Activate this ability only any time you could cast a sorcery.)
Whenever you activate Skull Kid's melody ability, you may discard a card at random. If you do, each opponent chooses a permanent they control at random and sacrifices it.