Really fun game. I really like what you did with all the lights. Just dark enough that felt like I needed the flare gun and definitely set a spooky vibe. Also, the flare smoke particles were a nice touch. I also thought the level design was awesome, with how much verticality there was. Resource management was pretty well balanced.
At one point I did walk through a wall and fall forever, but that's pretty much my only complaint.
Great work, overall!