Elnaril, Netherborn

Whenever Elnaril, Netherborn enters the battlefield or deals combat damage to a player,
exile the top card of each player's library. Until
the end of your next turn, you may play those
cards.
Whenever a player plays a card from exile, you
may pay {u}{b}{r}. If you do, return Elnaril,
Netherborn from your graveyard to the
battlefield.