Abaz, the Cruel-Hearted

Fear, deathtouch, partner
Whenever Abaz deals damage to a player, you may pay {1}{u}{b}{r} . If you do, gain control of target creature that player controls.
Whenever a creature you control that you don't own deals combat damage to a player, that player pits that many cards from the top of his or her library into his or her graveyard.