Ainz Ooal Gown, Sorcerer King

When Ainz Ooal Gown, Sorcerer King enters the battlefield, if you haven't completed The Great
Tomb of Nazarick, return Ainz Ooal Gown,
Sorcerer King to its owner's hand and venture
into the dungeon.
Whenever Ainz Ooal Gown, Sorcerer King
attacks, for each opponent, you create a 2/2 black
Zombie creature token unless that player
sacrifices a creature.