Echo.
Spawn Frost on both enemy rows for 3 turns.
Echo: At the beginning of the round, move this card from the graveyard to the top of its owner's deck. Give it Doomed.
Spawn: Add a card to the game.
Frost: At the start of the owner's turn, damage the highest power unit in this row by 2.
Very useful for travels to other dimensions and bringing apocalypse upon the world.