Dreameater Kami

Flying
Limbo {u} (You may exile this card from your hand for its limbo cost at any time. You may return it from exile to your hand anytime for its limbo cost.)
When Dreameater Kami is in exile, at the beginning of each player's upkeep, starting from you, he or she puts the top card of his or her library into his or her graveyard.