Zero, the Chessmaster

At the beginning of your combat step, choose a creature
an opponent controls, and gain control of it.
That creature gains haste and your choice of
death touch or unblockable until end of turn.
If that creature dies, that opponent discards a
card, loses 1 life, and you create
a 1/1 Soldier creature token.
"To defeat evil, I shall become an even greater evil."