Death of Nissa

Destroy target planeswalker.
Flashback {3}{b}{b} (You may cast this card from your graveyard for its flashback cost. Then exile it.)
With the Gatewatch in shambles after Gideon's death the remaining members retreated to their home planes to defend against Nicol Bolas and his army of worthy. But as Nissa returned she fell into Ob Nixilis grasp and fell to his renewed powers.