hey guys if you don't know what a knock back mod is it's a modded custom game i have where you can copy into your own MW3 vault. when you get in the game with a friend you pick the shotgun class and when you shoot each others heads you go flying. if you don't understand then look it up on Youtube to get the gamemode add "xX Dr Chill Xx" as a friend and i will accept it long enough for you to get the game mode. the game mode is called "PwNeD"
hope this helped
to copy this into your own vault, go to vault > Friends online vault > click xX Dr Chill Xx > and click on game mode to copy to your own vault then play.
rep and thx please