I'll give fair warning about the Nazi zombies, the higher the level the harder the zombies are to kill. I found this out by cheating, not in co-op but in single player mode(yes they do have it for single player fancy that). The best weapon is the ray gun that you can get from the help room. Btw the help room is the easyist to defend as it has only the door, two windows and a tunnel. If you open the upstairs room you will die!!! Also what are your usernames for multiplayer and co-op? Mine is Patton521, and on the topic of our own clan I think that would be sweet! I'm tired of playing against those uberdoucebags on multiplayer
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