I think I'm in!
I always take the ultimate decision to the last minute. Last night, couple hours before the theme was out, I thought about doing it in Godot, but was having some hard time to setup a good environment in Windows using Neovim in WSL. So I decided for Zig+Raylib. But took me a while to setup stuff. Then the theme was out and I was like... huh, I started working on a swarm fish mechanic some time ago, in an unfinished game for JS13K 2023.
So I decided to use the boilerplate code I created for that project and also the fish mechanic and make a new game with it. So far that's how it's going:

Although there's a extermination of fish in this gif, your actual goal is save them rather than kill. Of course some casualties will be forgiven. :)
The idea is make all the graphics procedurally, I'll try to stick to it.
So here's my technical overview:
- Platform: HTML5/Javascript
- Libs:
- Three.js: mostly for post-processing, graphics are procedurally created in Canvas
- Pizzicato.js: for music
- jsfxr: for sfx
- Editor: Neovim
- Music Editor: Reaper
Have a good compo you all!