Hacking on Chicago 35 on 07/05/12 between 10:20p.m. and 10:40 p.m. central. A player would disappear in and out really fast always in different spots. He seemed to be invincible to the zombie horde I attacked him with. He was flying a helicopter that I don't think was a Huey and had a weapons crate outside of it. This all happened on North-East side of Cherno. Minutes later when all my buds and I were re-spawning everyone suddenly glitched and flew in the air and died simultaneously. Complete crap... Sorry I don't have names as I didn't know how to check. I did take a snapshot of the player list after this all happened but I don't know if he was still in server or not when I took it. Lemme know if that helps.