Really fun game! I love how it looks and the gameloop feels nice. It's one of the better diving games this jam, since it's actually unique, being themed around crystals and not just an underwater submarine with sharks or something
What I don't like is the balancing of the upgrades, Light is completely useless because everything you need to see already glows in the dark, Boots are only useful in a couple cases, so it's still good to grab them, but they don't stack (at least to my knowledge), so you would only want to get them once, and any time they appear after that they're useless, Attack speed isn't super useful either since the starting attack speed is already quite fast, and going any faster makes it be basically as fast as you can press Ctrl (which, by the way, please rebind that to something else, it hurts my pinky finger), so the only three upgrades worthwhile getting are Movement speed, health, and Crystal Magnet (which, is also only useful once, because i assume crystal magnets dont stack).
Also, shops can be REALLY spaced out, i collected 200 gems before seeing a single shop, which gave me the option to buy two boots, which i had already bought in the last shop, after that i went on to collect 200 more gems and eventually die due to the lack of healing.
Enemy balancing is also quite wack, the only two enemies that pose any sort of threat to the player are the shooting ones, and the flying ones, the other two are just murder victims.
I really like the game, but the weird balancing makes it frustrating to play.