A day will dawn when the premise "what if Darkest Dungeon but also XYZ" will lose its crablike stranglehold on my fancy, but that day is not this day, for today we Dive or Die. Not that the two activities are mutually exclusive.

In this 2D roguelite scuba sim from Drop Rate Studio and publishers Dear Villagers, the world has succumbed to a "black rain" that inflicts mutations and nightmares. It's been chucking it down for five solid years, in fact, with human civilisation reduced to scraping a living on mountaintops that are now islands. There isn't much of a living to scrape on mountaintops, so off you go into the "abyssal pool" to dredge up some canned food and building materials.

DIVE or DIE - Launch Trailer Watch on YouTube

20 or 30 metres down, all you really need to worry about is some touchy-feely carnivorous algae. It's almost... serene. But then you poke your head into a cave, perhaps hunting a crafting blueprint or some iron for a base upgrade, and whoops, something has poked its head into you.

As with Darkest Dungeon's cast of mercenaries, individual Dive and/or Diers are both fragile and disposable. They level up pretty fast, but they also sprout foibles and afflictions to match the shrinking of their sanity bars. When not paddling about in flooded catacombs, you can station them in your base buildings for various resourcing benefits.

The major overarching worry is the coming of the Rainmaker, a sky-scraping squidgod and the source of the black rain. No, not a hotshot lawyer, though well done you for knowing your John Grisham.

Each run, you're given a countdown till the Rainmaker rocks up and unleashes the final tsunami. To prolong the countdown, you must gather certain relics from the ruins below. While it's hooked up to a familiar vein of eldritch, I'm enjoying the location and monster design: you'll fumble down old elevator shafts and delve into labyrinths of tombstones, all the while avoiding and, if you must, battling creatures that consist mostly of elbows and incisors.

I've unlocked a dartgun in the demo, which spans the first 10 in-game days, but I'm in no mood to pick fights. Though I do hold out hope of it suddenly coming over all Barotrauma and handing me an actual submarine. Find the demo on Steam, for a little while, anyway – the full game is out today.