Ulamog's Nullifier

Devoid (This card has no color.)
Flash, Flying, Ingest 3

When this creature enters, you may put five cards
an opponent owns from exile into that player's
graveyard. If you do, counter target spell.

{t}, {1}{u}{b}{c}, Sacrifice this creature, Put five
cards an opponent owns from exile into that
players graveyard: counter target spell.