Fishitting
Fishitting looks like a scrappy survival loop (forage, collect, upgrade, brighten) right up until it isn't. The brighter your light burns, the more fish it summons, until the crowd snaps the anchor rope holding you down. Freedom, the surface, and then the pollution that was waiting there the whole time.
Light is the whole economy
You play a fish tied to the seabed by an anchor line. Forage to hold off hunger, then drag scrap (glass, batteries, metal) to your broken light and upgrade it. Every upgrade widens your vision and lengthens the rope, so brightness, sight, and how far you can roam all grow together.
Other fish don't make it easy: they barge in and knock your hard-won materials loose. Your answer is the ammunition the game is named after: hold to charge (you slow to a crawl), release to fire, and the troublemaker is blinded and driven off. Clearing fish feeds the light too.
The brightest light is the trap
Brightness is the goal and the undoing. Push the light to its brightest and it stops being a tool. It becomes a beacon, pulling in more and more fish until the crowd's sheer weight breaks the rope that's held you down the whole game.
And then the real point lands. The fish tears free, swims up toward the light at the surface it's been reaching for, and dies there anyway, in water too polluted to live in. The escape was never the ending; the ocean was.