If you head on over to GameTrailers.com and watch this video, just after the mirrors preview level you’ll get to see an exclusive look at the Nazi Zombie Co-op mode that is unlocked once you beat the solo campaign. It actually looks really fucking cool. It sounds similar to Gears of War 2’s Horde mode, but you and 3 other people are trying to protect yourself from Nazi Zombies that are trying to kill you. The cool thing about it is that you build up money and can use that money to keep the windows boarded up, buy new guns, move objects out of the way, etc. I thought that aspect of this game mode is really cool and apparently, unlike Gears of War 2, there is an unlimited amount of rounds. So you basically go until you die and Treyarch’s only been able to reach level 23 according to them.