Unknown Worlds launched Subnautica: Below Zero in early access almost two and a half years ago, and the full version of the game is finally arriving on nearly every platform available. Originally intended to be DLC for Subnautica, the game grew into a full-fledged sequel that takes approximately half the time to beat as its predecessor. Set two years after the events of the first game, the player takes on the role of a new character, Robin, who travels to Subnautica’s Planet 4546B in search of her missing scientist sister. After inadvertently crash landing in an Arctic region of the planet, Robin has two goals: find out what happened to her sister and survive.

Any fan of survival games will doubtless enjoy Subnautica: Below Zero, but Unknown Worlds’ follow-up title will please even newcomers to the genre. The learning curve, while a bit wobbly at first, isn’t so high as to be dissuasive. The game strikes at people’s innate needs – sustenance, air, heat – and instincts will kick in even if tutorials don’t, and that almost makes success that much more fulfilling.

subnautica below zero review plants

The first thing that will strike any player upon loading the game are the incredibly breathtaking visuals. This is not a dull green ocean with a featureless sandy bottom, wilting seaweed, and the occasional discarded plastic bottle drifting by. This is a world filled with vibrant sea and plant life, many of which glow and brighten the waters with a range of mesmerizing colors. It’s easy to get caught up in the environment and the game’s intuitive base-building mechanic, forgetting momentarily that this is a survival game with the demand for food, water, and air requiring constant attention.

Even though it’s a standalone title, it seems safe to assume that many people diving into Below Zero will already have played the first game, and the sequel will be very familiar as far as graphics and gameplay. The PDA that serves as a repository for all useful game information is almost identical, with the only noticeable and very useful difference being that blueprints can now be pinned, allowing required materials to be viewed easily from the HUD. The majority of the tools, food items, flora, fauna, gear, and vehicles found in Subnautica haven’t changed much either, but there are some fun additions that will prevent players from feeling too much déjà vu. There are a few new gadgets to play with, as well as unfamiliar plant life and creatures to become acquainted with or flee from.

subnautica below zero review sea monkey

Below Zero introduces two new vehicles, the Snowfox and Seatruck. In the game, players will spend a bit more time on land than they did in Subnautica, and the landscape is snow covered and inhabited by aggressive Snow Stalkers. This is where the high-speed all-terrain Snowfox hoverbike comes in handy, allowing players to quickly cover a lot of ground and make some getaways if necessary.

The Seatruck is exactly what it sounds like, a maneuverable undersea vehicle that can be customized with various modules that attach to the back, forming a kind of train. For example, the storage module features plenty of lockers to store items found while exploring far from base. The aquarium module has two tanks and sucks up any unlucky fish that venture too close, providing a useful way to capture sea life for food or display without having to chase things down manually. The Seatruck is an extremely useful addition that players will want to unlock as soon as possible, though attaching too many modules will make this vehicle unwieldy and prone to damage.

subnautica below zero review seatruck

Subnautica: Below Zero is incredibly successful at evoking a feeling of exploration and discovery. After carefully packing the Seatruck with provisions and tools, a player might set out with a specific task in mind: "Okay, off to that shipwreck!" Twenty minutes later, they will find themselves instead mining a newly discovered mineral, 400 meters deep within a narrow chasm filled with phosphorescent flora and perhaps dangerous sea life. And they won't mind. The underwater world of Below Zero feels vast and almost limitless, filled with secrets, many of which will lay forever unseen within caverns and the decaying remnants of prior expeditions.

The game offers a wide range of biomes to investigate and enjoy, each markedly different from the next. There is of course an Arctic biome, with stalactites of ice growing inexorably toward the ocean floor and hapless sea creatures turned into barely identifiable ice sculptures frozen to the sides. There are glowing thermal vents, forests of Creepvine swaying in the currents, dark depths filled with giant whale-like animals and even larger lily pads, and claustrophobic winding tunnels that lead to mysterious alien structures.

subnautica below zero review cave

These areas aren't all open to the player from the very beginning. Access is doled out at a steady and satisfying pace, as the player finds data pads and broken machinery, unlocking item blueprints that provide ingress to other parts of the world. A rift with an intriguing red glow on the distant bottom might be unreachable until a blueprint is found that provides a larger oxygen reserve, thereby allowing exploration at greater depths. Rusted doors in shipwrecks, which surely conceal treasures, cannot be opened until the recipe and materials for a laser cutter are uncovered. Curiosity and persistent poking into every hidden nook rarely goes unrewarded.

This freedom to explore means that the player almost never gets bored. Below Zero also provides regular guidance, with beacons or recorded conversations supplying clues about key locations to investigate. While Subnautica sometimes left the player feeling a little uncertain about what to do next, Below Zero is slightly more story driven, but not to an excessive degree. The ability to freely explore the open world remains, but now there are also scripted sequences, a few cutscenes, and plot points to keep the wandering player from perhaps straying too far.

subnautica below zero review base multipurpose

Base building is another integral component of Below Zero’s draw. Anybody who’s gotten caught up for hours constructing a base in Valheim or erecting a complex CAMP in Fallout 76 will know the allure. While perhaps not as in-depth as the mechanics in those games, crafting a seabase in Below Zero is just as compelling. Though many of the base pieces and modules remain the same as those available in Subnautica, there are a few additions, most notable among these being the Large Room, which provides much more space than the spherical Multipurpose Room and therefore greater opportunities for personalization. The developers have even added the components for building a bathroom, complete with toilet and shower.

In developing Subnautica: Below Zero, Unknown Worlds heeded the lessons learned from Subnautica and the feedback received from players about both games over the years. Below Zero has taken no steps backward and instead offers an even more polished experience than its predecessor. As for gameplay and story, it’s not necessarily a better game, but it is certainly just as good.

Subnautica: Below Zero releases on May 14 for PC, PS4, PS5, Switch, Xbox One, and Xbox Series X/S. Game Rant was provided a Steam code for this review.