David

[+1]: Until your next turn, prevent all damage target permanent would deal.
[0]: Until end of turn, David the protector becomes a 4/4 Human Soldier creature with indestructible that's still a planeswalker. Prevent all damage that would be dealt to him this turn.
[0]: You get an emblem with "As long as you control a David planeswalker, you can't lose the game and your opponents can't win the game."