Jokulmorder [Coldsnap]

Set: Coldsnap Type: Creature — Leviathan Rarity: Rare Cost: {4}{U}{U}{U} TrampleJokulmorder enters the battlefield tapped.When Jokulmorder enters the battlefield, sacrifice it unless you sacrifice five lands.Jokulmorder doesn't untap during your untap step.Whenever you play an Island, you may untap Jokulmorder.