It works solo to lol you need only 1 zombie a nuke you have card for that to... and go to the bumper cars place the nuke By the door when you see the bump car wil drive you over press L1 so long ass you can to hit the nuke to let you respon (don't forget to buy self revive 500 score by the begin on the right side) i did not find this glitch i try this on my own to get high chene and full XP boost for my level and weapons... you Will not be banned for this... its game bug not a hack...