Stealer of Identities

At the beginning of combat on your turn, you
may pay {u}{b}. If you do, exile 2 target creatures. Until end of turn, this creature gets +X/+Y, where X is the first exiled creatures power and Y is the second exiled creatures power. At the beginning of the next end step, return the exiled creatures to the battlefield under their owners control with 2 -1/-1 counters on them.
Hexproof