Liliana, Waker of the Dead

+1: Each player discards a card. Each opponent who can't loses 3 life.

−3: Target creature gets -X/-X until end of turn, where X is the number of cards in your graveyard.

−7: You get an emblem with "At the beginning of combat on your turn, put target creature card from a graveyard onto the battlefield under your control. It gains haste."

Format legality