Ulamog, the Defiler [MH3 - 15]

Rarity: M #: 15 Creature Type or Sub Type: Legendary Creature — Eldrazi P: 7 T: 7 Rules Text Contains: When you cast this spell, target opponent exiles half their library, rounded up. Ward—Sacrifice two permanents. Ulamog, the Defiler enters the battlefield with a number of +1/+1 counters on it equal to the greatest mana value among cards in exile. Ulamog has annihilator X, where X is the number of +1/+1 counters on it.