I'm amazed you were able to pull that much work in such little time. You nailed the aesthetics and vibe of the games of the era and the gameplay is solid enough.
The zombies could be more threatening though, they end up being pushed around or ignored with no problem. Even the horde, I was backing up and letting my bots friends handle them. I agree with the other comment about the map, the fact we can run through the maze is creating problems.
Overall an impressive work!