Nice entry, well polished. Though it was in a way fairly light on the story, it did have a beginning, middle, and rewarding feeling end so that hits the mark! Everything fit together quite nicely - even your itch page, nice to see what you learned.
Only suggestion: It took me a few hits before I realized it’s just medium gray rocks which are solid, while the dark is a cave. It meant during gameplay, I’m having to discern between color ranges instead of just “light = open, dark = solid” or something like that. I get that a cave needs to be darker though, maybe some dither transition from the open water to help show that it’s a transition into the cave part could help?