Breaker of Worlds

Zenith Empyrean - (While you have this as your Empyrean, you can't have any other empyreans.)
Indestructible, Trample, Hexproof
Whenever Breaker of Worlds deals combat
damage to a player, you may search your library
for a card, and exile it. You may play that card
this turn without paying its mana cost. If you
play that card, it can't be countered if it's a spell.