really neat little game! the tutorial was a nice introduction to the mechanics. i think the text could have been placed better in some cases to make it easier to read from the direction you’re moving.
i found descending to be a little slow and moving through the corridors was more challenging than i expected it to be. it feels like you bounce off of walls/spikes quite a bit and that made it feel like i lost control of the movement. also doesn’t seem like you have enough air to actually get much treasure since it takes so long to get to it. so unfortunately i didn’t get too far before getting frustrated and giving up.
the graphics are nice! i would add a few more screenshots to your page to help give players more of an idea of the gameplay. really cool background on the page also. i really like the music despite it being a bit short and repeating. it definitely sets the mood of diving for treasure.
overall nice job on the game! i think with some minor tweaks i would enjoy it a lot more, but it could also just by my own personal preferences.