If you have a computer player on your team (so that means atleast 1 human and atleast 1 computer) then when the computer player losses all of the lives, press start on any controller in a slot. Then take out any controller and stick it in the slot of where the computer player is and press start on that controller. Switch the controller back and press start. Viola the computer person "stole" one of your teammates lives or one of your lives. It goes by whoever has the highest amount of lives gets a life taken away.