Whenever you attack with two or more non-Gideon creatures, put +1/+1 counter on each of those creatures.
+2: Until end of turn, Gideon the Oathsworn becomes a 5/5 white Soldier creature that's still a planeswalker. Prevent all damage that would be dealt to him this turn. (He can't attack if was cast this turn.)
-9: Exile Gideon, the Oathsworn and each creature your opponents control/