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."