Ob Nixilis, Immortal Pact

+1: Destroy target creature or planeswalker. Draw a card and lose 2 life.
-3: Draw 3 cards and lose 3 life. Each opponent sacrifices a nonland permanent they control.
-7: You get an emblem with "You can't lose the game and your opponents can't win the game as long as you control a planeswalker".