Submergency
Great ambience off the bat. The choir and string quality is excellent. The light water SFX is very well balanced. Wow, huge turn in the music, really gives that epic feel. Wide variety of instrumentation and feelings. Really great track, the fade out of the synth at the end feels a little off to me, I think it would sound better if it was solo piano at the very end, but that's subjective.
Sea Frog
Great intro, great underwater feel. SO groovy! Sounds like a great track for a level. Overall just impressive, so many moving parts, so energetic and wacky. A good tune.
abyss eyes
Ooo, great contrast to the other tracks here. A more creepy feeling, so very ambient, love the distance/reverb/muddyness of everything. Then it feels like it "shines", like light cutting through water. I appreciate how it's a bit more minimal than the other tracks, which in my opinion is great for a more horror-esque feeling.
Final Breath
Good build up, though it doesn't have the underwater feel the others have, though perhaps that's intentional based on the title? Excellent epic sections, composition-wise I feel it is very well done, but I would say it's the weakest track compared to the others. It doesn't feel as fleshed out, and I don't feel the core theme of it quite as much.
I wish there was more description of the game itself and how you visualize each track within it, what they represent, as I feel that would really improve the listening experience and give something else to connect feedback to. The creativity when it comes to the game idea is something that I personally value. The idea was very straightforward, and I feel you could push yourself when it comes to this aspect should you do this or a similar jam in the future.
That aside, the composition and mixing here is very impressive in my opinion. Musically, you seem very skilled! You should be proud of this submission. Best of luck to you. <3