Haven't finished yet, but...
This game is incredible! Probably the most detailed gameplay I've seen in the game jam, and it really makes me feel like I'm operating a massive machine deep in the ocean. The music and sound design are really well done too. The pixel art is all really high quality and the 3d water effect at the top of the ocean is super cool. On top of all that it's polished and nothing really seems broken (except somehow I can't repair my sub a second time). That's saying a lot for a game jam! The only thing I would have hoped for were some more detailed instructions on how the game works.
Awesome job!