I think it was cool that you took the theme and turned it into a FPS experience, which made the atmosphere a lot darker and suspenseful than usual. The lighting was nice, and the visual/sound effects made the ice spirits quite creepy. The only problem was the movement, which was a little buggy and wouldn't move exactly in the direction you pressed. If you moved forward, turned left and pressed forward, you'd still move in the direction you were moving before for a bit. I also think it was a bit unforgiving in that if you missed even one shot you'd get swarmed by monsters pretty quickly. If those things were tweaked, as well as some settings to adjust FPS sensitivity etc. it would make a pretty good shooter game.