I like the atmosphere, it feels like a spooky environment, but I feel like the game needed a little bit more to spice it up. The gun gives a little kick when firing, slow to recharge, and causes a explosion on enemy impact. I bet it would be cool to implement a rocket jumping type mechanic based off this. Good job on creating it within Unreal, I have not touched it myself but I bet it is high end and requires a lot.