Death In Abyss is a creepy submarine action game in which your ship does the backstroke

rockpapershotgun.com:

I have played many a creepy throwback game that takes inspiration from the ever inadequately named "Golden" (Grimy and Diseased? Cadaverous, perhaps) Age of survival horror on PS1, but it's rare you play one that invokes the N64, and even less often that you stumble on something horror-adjacent that riffs on Star Fox 64. Ah, Star Fox! The natural companion piece for, say, Eternal Darkness or The Suffering. In fairness, I did always find those Pez dispenser dialogue animations pretty eerie.

The work of Norwegian dev Agelvik, Death in Abyss (Steam link) is a third-person "submarine action game" in which you explore a noxious ocean full of angry, bioluminescent brains and what I hope are ravenous tadpoles, though other possibilities occur. You're here to shoot everything in cold blood, of course, but there's room for some whimsy along the way in the shape of your craft's movement. Put it in reverse, and it does a cute little backstroke. Seriously, look at this trailer. I can't get enough of it. If I am ever rich and stupid enough to buy a submarine, I want one that moves like this.

Death In Abyss also takes inspiration from the slaughterous Devil Daggers and the anime Made In Abyss, which I haven't seen but understand to be pretty unpleasant, and possibly Problematic. Agelvik's past works include Gun Devil, God Damn The Garden, Apple Slash and Lulu's Temple, all of which channel a particular blend of upbeat and macabre I find very appealing.

There's a Death In Abyss demo coming in July, all going to plan. If this is your cup of mutant herring gizzards, the recently launched Underspace might also grab you. It's similarly abundant in oceanic monstrosities, though it's a sprawling Freelancer-like rather than a level-based action experience, and doesn't, as far as I know, feature any backstroke-capable spacecraft.