Avatar Aang

+2: Target creature gets +2/+1 and "prevent all combat damage, that would be dealt to this creature" until end of turn.
-3: Avatar Aang becomes a 5/5 white Human creature with indestructible, flying and first strike that's still a planeswalker until your next turn.
-7: Target creature loses all of its abilities and gets -2/-2 until end of the game.