This game was quite frustrating at some points. Dying at 0 meters send you back to 400 meters which felt a bit unfair. If you look at the wall during the monster encounters, it feel like his position locks on to the wall that you look at even if you are trying to look away from it. To be fair the people watching me play this did enjoy the "hell" I was going through when playing. I was extremely determined to get to the end because i hoped there was going to be some form of payoff but there unfortunately wasn't. I guess there's no payoff in hell... Personally it felt like the game lacked the little things. Maybe new textures on the tunnel every once in a while, maybe the tunnel changes shape, maybe there's a fork in the road, maybe there's a random sound effect that plays. Things of those nature. Given the time frame I can understand how that may be difficult to implement, but maybe something to note for the future. I will say I did enjoy having to use sound to avoid the monster and the monsters design was interesting but could definitely be improved upon in terms of textures so it looks more menacing. I believe you have a cool concept here and this could be a good project to continue working on in the future.