Darklord Zerato (PTDN-EN081) - Phantom Darkness Unlimited

If there are 4 or more DARK monsters with different names in your Graveyard, you can Tribute Summon this monster by Tributing 1 DARK monster. You can send 1 DARK monster from your hand to the Graveyard to destroy all monsters your opponent controls. If you activate this effect, destroy this card during the End Phase of this turn.