Ashiok, Shadowborn

+1: Until end of turn, whenever you surveil, each opponent exiles the top card of their library. Surveil 1, then draw a card.
-X: Create a blue and black X/X Nightmare creature token with "Whenever this creature attacks, Surveil 2."
-7: Until end of turn, you may cast cards from your graveyard without paying their mana costs.