tips for final boss: use a high lv chain or wave to get through his 'shields'; don't pay too much attention to dodging the large lasers, just focus on the blue ones; use overdrive every chance you get; use a secondary that you can hit the center of the screen while you're on the top or bottom of the screen (missiles work best).
this is stupid, it keeps glitching, the worst was the gun that couldn't kill a peice of paper, the next worse was when I beat it and it said I cheated so my score was invalid. HOW DO YOU CHEAT!?!?!?!?!?!?!?!?
my main problem: the fact that zombies are also ghosts. I mean, they can walk through walls and you miss headshots from 50 meters even if you have a weapon on a scope on it...