Also never figured out the melee, but the gunplay was really well done.
Pathfinding was, generally, really good - impressive to see the AI make their way to me.
The overall mechanic was intriguing, and you matched the theme very well. I liked how hitting monsters didn't kill you, but took your time away rapidly.
Just a bit of sound would have really helped bring it to a high level of feeling complete.
Great job!