hey wojjan, there i no end, every level is impossible, and nightmare is easy, you just suck, and masterchief (uncreative nerd) if you shoot a barrel it will explode, what kind of plan is that now? try my strategie (6 comments down)
i know a secret! when in defense mode, use the barrels in front of zombies and a turret will shoot it, keep unloading barrels because you then have an explosive tail! it works best on expert and nightmare.
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