Dauthi Voidwalker

Shadow (This creature can block or be blocked
by only creatures with shadow.)
If a card would be put into an opponent's
graveyard from anywhere, instead exile it
with a void counter on it.
{t}, Sacrifice Dauthi Voidwalker: Choose an
exiled card an opponent owns with a void
counter on it. You may play it this turn without
paying its mana cost.