I totally agree with everyone who said that there should be some sort of level structure, as well as not just being wave after wave of endless zombies..but should be placed strategically..as well as ammo not falling from zombies who have no place to hold ammo ..it should be picked up alon the storyline of the game. the game should definately be mission based, with keys and puzzles and all that fun stuff. Yet i still say you have created one of the most detailed games ive ever seen on newgrounds, bring it back with a new installment and im sure it will be one of the top games on the site.
Ps loved the little details, like the shotgun blasts having their seperate flashes when it hits the wall! 10/10 for sure