Maliketh, the Black Blade

Menace, Trample, First strike

When Maliketh deals combat damage to a player, that player puts doom counters on a number of nonland permanents they control without doom counters with combined mana cost equal to or greater than the player damage dealt.

Sacrifice Maliketh: Exile all permanents with doom counters on them. You may cast a card from your graveyard with equal to or less mana cost than the exiled permanents.