The atmosphere of the game was really good and exciting. Too bad I wasn't skilled enough to finish the game. But I really enjoyed the journey till the end!

This is really cool, especially for your first game! Enjoyed swimming around and navigating via the radar.

It's great that you are able to add a boss fight in it.
But sorry the boss is too difficult for me.

Not bad for a first game, especially when you've done it under jam constraints. The initial exploration was nice, the boss fight could have used a bit of tuning. Tried it a couple times, and the vertical attack would just force me to the side, trap me, and kill me, sub wasn't fast enough to avoid it. Telegraphing the attack with the red box was good though, even if it only served to make me realize how doomed I was lol.

You really did a nice job with your game. Controls are good except I would use the left mouse button to fire the torpedo. The sound effects and the music was good.

What is the big blue guy at the end?

You forgot to remove the fishes on screen when changing the scene!
The phase2 of the boss fight seems impossible to beat, for I do not have chance to restream. Maybe that is because of forgetting adding invincible time after getting hit?

The atmosphere is well done, with the sea getting darker and creepier the further down I went. The whiplash of the giant octopus boss fight got a good laugh. It took several attempts to actually beat it, as his damage is nearly instant death. Some invincible frames when hit would make the fight feel more balanced, and reduce the number of times I had to dive back down.
It would have been nice to see some change in the ending based on how much exploration was done. The enemies staying between screens was interesting. Good work!