This was really cool, love the whole underwater style and worldbuilding. Appropriately difficult/satisfying mix of exploration and guiding the fella.
One criticism (bug?) is that seems like oxygen rate is tied to framerate. Died a lot to figure that out
Assuming there was nothing else to see after leading it to the big guy? got a black screen. Otherwise really liked how it got more creepy and dark as you get further down near the end