Subnautica: Below Zero review — life begins at minus 30

I’m planning a trip. I’m going to load my sea truck with provisions, pick a direction and travel as far as I dare before pitching camp on an iceberg. First up, I need to craft a compass; while I’m doing that, I might as well make a bunch of beacons to mark points of interest for later. I could also do with some sea truck storage compartments (you know, for all the beacons). I pin the recipes to my heads-up display and go for a dive, hoping to pick up some crafting materials, but as I explore deeper, the sentient AI that has taken up residence in spare bits of my cerebral cortex (don’t ask) notifies me that there’s something interesting nearby. Topping up my oxygen regularly to avoid suffocating as I crawl over unexplored parts of the seabed, I stumble upon an abandoned underwater science outpost and start picking through it for salvage and intel. There’s an interesting crafting recipe here… wait, wasn’t I planning a trip?

Subnautica: Below Zero is an underwater survival game where best laid plans, like my theoretical sea truck escapade, are often diverted toward interesting distractions. As scientist Robin Ayou, we descend on planet 4546B to search for her lost sister, Sam, but the more immediate priority is staying warm, fed and hydrated (and making beacons). Starting out from little more than an aquatic linen closet with a fabricator and a tiny storage locker, the early hours are spent scavenging for fish and scraps to stay alive and fashion basic tools. There is no combat, just survival.

As is the way of such games, fish and tiny storage lockers are soon replaced by reliable food traps and hulking equipment containers as you expand your base, and your linen closet becomes a footnote to a sprawling undersea habitat like something out of The Abyss. Swimming around the seafloor becomes easier too as you increase mobility and oxygen capacity, and while drowning or being consumed by angry leviathan predators are always possibilities, in general you gain more command of your environment as you climb an ever-growing ladder of resources and upgrades. Robin’s is a freeform adventure with no breadcrumb trail of tasks to complete, but there’s always just enough information and suggestion to help you solve your immediate problems.

It’s a formula that has been done to death over the past decade, but Subnautica: Below Zero has planet 4546B on its side. 4546B may sound like a punishing addendum to a tax return, but it’s a beautiful place to explore, full of colourful environments, each of which yields a new cocktail of raw materials. You swim under crystalline ice floes, among mazes of coral archways and through iridescent cave networks, weighing the risk of suffocation against the likelihood of oxygen plants in the next cavern.

While the general theme is exploration and expansion, there are strong narrative hooks that tug at you here and there, whether it’s the mystery of your sister’s disappearance or the desire to get that alien AI out of your cerebellum, and these occasional nudges towards bigger questions and puzzles thread neatly through your survival rituals.

This can be a fiddly game, and certainly isn’t one for people who dislike mining or organising elaborate storage systems, but after a couple of years in Early Access this is now a refined and elegant experience, gently paced, where there is always something interesting to pursue through beautiful spaces. Voluntary isolation in the deep cold might not sound like solace after a winter of lockdowns, but Subnautica: Below Zero is cosy and moreish. Dive in, and you may be surprised how deep you end up going.

• Subnautica: Below Zero is out now; £25-£50 depending on format.