I'm totally overwhelmed - they come in swarms, like zombies! Honestly, the concept is quite cool, and it's been a while I finally get my hands back on the original doom POV. I myself can hardly find a good way to intertwine math with doom - one requires precision, the other is complete chaos. Well, now I see ;))
The only problem I found myself in is the fact that after you get killed you get back to main menu. It's more unintuitive to do so than to, let's say, give the player a health bar, and when they die they get a losing screen or something like that. That's it for my feedback. Keep up the good work man!