Great game! I loved the idea. I have two suggestions to make though:
1. I think the player should start with the torch, rather than the gun. I often found myself switching to the torch as soon as the level started anyway. You need to see what's around you after all.
2. It might be a good idea to add some sort of delay time for the gun between the shots. Like, maybe I shouldn't be able to fire faster than 2 bullets per second. I realized the most efficient way to kill enemies was to just spam LMB as fast as I can.
Still, great idea, great presentation and tons of fun to play! Loved it!