Kex, Undead Shadow

Whenever a creature you control dies, if you have no cards in hand, you may return Kex, Undead Shadow from your graveyard to the battlefield. Pay 3 life, discard a card: Put a 1/1 black Scarecrow creature token with shadow on the battlefield
"He doesn't stay for more than a night. But that night will be the longest you'll ever witness...if you survive."