Emrakul, Scourge of Ravnica

Expose - Reveal an unrevealed card from your
hand: Emrakul, Scourge of Ravnica costs {1}
less to cast until end of turn.
Flying, trample, protection from multicolored.
Annihilator 4 (Whenever this creature attacks,
defending player sacrifices four permanents)
Even death fears annihilation.