Invasion of Kaldheim

(As a Siege enters, choose an opponent to protect it. You and others can attack it. When it's defeated, exile it, then cast it transformed.) When Invasion of Kaldheim enters the battlefield, exile all cards from your hand, then draw that many cards. Until the end of your next turn, you may play cards exiled this way. Pyre of the World Tree Discard a land card: Pyre of the World Tree deals 2 damage to any target.

The Warriors of Kaldheim burned the soul of their world to keep it out of Phyrexia's hands.