One of my favorites I've played so far to be honest. I'm just a sucker for weirdness, and this checks all my weird boxes. The art is sort of goofy and sort of offputting and just creates a great uncomfortable vibe to the whole thing. Also, you say you ran out of creative names, but I feel like Fish Monstrocity Arena fits the vibe surprisingly well, haha.
Despite my love for this conceptually, it's definitely lacking some polish. Descriptions for what each component does would help a lot I think. The battles themselves felt a bit anticlimactic, in part because I had a hard time telling what was going on and what actually made a victory or a loss. There's some other things (giving the game some juice, tutorializing) that others have mentioned as well.
That said, I still loved it. I'm glad it sounds like you have plans to continue working on this after the jam because I would love to see where it ends up. Great work!