There is a lot of potential with this idea, I love underwater horror games in general but the atmosphere here is done really well. The cave system is beautifully done, that combination of low-rez textures mixed with the blues and reds is very unsettling to look at, plus the sheer darkness was quite daunting to move through. It was quite easy to get lost and turned around but that did add to the uncomfortable atmosphere. I like the use of the coordinates to figure out your position, it did add a bit of challenge to figuring out where to go and the touch of having positions change was very effective. Personally I think you could have just had regular movement controls rather than the dash, you wouldn't lose any of the tension and the dash did start to get annoying to use (not to the point of not wanting to play and this is just my personal opinion rather than an objective criticism). I also feel like the ending was a bit strange. Considering all the noises and effects that kept coming up (including sounds that really shouldn't be at the bottom of the ocean) I thought it was going to build up to something big but it ended quite suddenly. Not sure if that's just because it's a demo and this is literally the cut-off point to be continued in the full game rather than an actual ending, but it did throw me off a bit. I'm curious to see what direction you take with the full game. Really enjoyed playing this great little horror experience and I can't wait to see what you do next.