Subnautica: Below Zero
Released May 2021
Dive into a freezing underwater adventure on an alien planet. Below Zero is set two years after the original Subnautica. Return to Planet 4546B to uncover the truth behind a deadly cover-up. Survive by building habitats, crafting tools, & diving deeper into the world of Subnautica.
90% positive · 108K reviews
Done
All announced content has been released
High confidence
Done
All announced content has been released
High confidence
Where to buy
Steam $29.99 IndieGala Steam key $29.99
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Evaluation
Subnautica: Below Zero launched out of Early Access on May 14, 2021 as a complete, story-driven single-player game. The developer has never announced additional paid DLC, expansions, or ongoing content plans for Below Zero beyond the base game. The only DLC listed is the official soundtrack, which released alongside the game.
After the 1.0 launch, Unknown Worlds shipped one meaningful post-launch update: the "What the Dock" patch on September 13, 2022, which added a Custom Game Mode, a new Seatruck Dock base piece, and various quality-of-life improvements. There have been no further feature additions since then. The developer has since shifted its focus to Subnautica 2, announcing its Early Access launch in October 2024 and promoting it prominently in an April 2026 sale event. A security hotfix was applied on October 3, 2025, and a bug-fix/polish patch was applied on August 12, 2025, but these represent maintenance rather than new content.
The April 2026 announcement post explicitly frames both Subnautica and Below Zero as completed prior games in the series, used to build excitement for Subnautica 2. The studio's creative energy has clearly moved on. Below Zero is a finished product — the September 13, 2022 "What the Dock" update appears to have been the last substantive content addition, and the game has been in maintenance mode since then.
Evidence
Developer hosts a free weekend and sale for Subnautica and Below Zero to promote the upcoming Subnautica 2 Early Access launch. Below Zero is positioned as a completed prior entry in the series.
'What the Dock' update added Custom Game Mode, a new Seatruck Dock base piece, bug fixes, and quality-of-life improvements. The last substantive content addition to the game.
Content
1 of 1 released · no outstanding content
Media
Details
Developer
Publisher
Unknown Worlds Entertainment
Achievements
13
Platform
Windows, macOS
Controller
full support
Steam Deck
Verified
Players
Single-player
About this game
Below Zero is an underwater adventure game set on an alien ocean world. It is the next chapter in the Subnautica universe and is developed by Unknown Worlds.
Submerge yourself in an all-new, sub-zero expedition in an arctic region of Planet 4546B. Arriving with little more than your wits and some survival equipment, you set out to investigate what happened to your sister...
Alterra left in a hurry after a mysterious incident. Abandoned research stations dot the region. What happened to the scientists who lived and worked here? Logs, items, and databanks scattered among the debris paint a new picture of the incident. With limited resources, you must improvise to survive on your own.
Swim beneath the blue-lit, arching expanses of Twisty Bridges. Become mesmerized by the glittering, mammoth crystals of the Crystal Caverns. Clamber up snow covered peaks and venture into the icy caves of Glacial Basin. Maneuver between erupting Thermal Vents to discover ancient alien artifacts. Below Zero presents entirely new environments for you to survive, study, and explore.
Survive the harsh climate by constructing extensive habitats, scavenging for resources, and crafting equipment. Blast across the snowy tundra on a Snowfox hoverbike. Cruise through enchanting and perilous biomes in your modular Seatruck.
Something undiscovered lurks around every corner. Swim through the giant Titan Holefish, encounter the haunting Shadow Leviathan, and visit the adorable Pengwings. Keep your wits about you. Not all creatures in this strange world are friendly.
Jump in, the water’s warm. The below zero temperatures of this arctic region pose a new threat. New weather conditions blanket above-ground habitats. Craft a toasty cold suit, sip on piping hot coffee, and warm up next to Thermal Lilies to stave off the chill.
What really happened to your sister? Who were the aliens who came here before? Why were they on this planet? Can we find solace from grief in truth? Below Zero extends the story of the Subnautica universe, diving deep into the mystery introduced in the original game.
Below Zero is created by Unknown Worlds, a small studio that traces its roots back to the 2002 Half-Life mod Natural Selection. It is the same studio that created the original Subnautica. The team is scattered around the globe, from the United States to the United Kingdom, France, Russia, Austria, Australia, Canada, and many more places.
This game contains flashing lights that may make it unsuitable for people with photosensitive epilepsy or other photosensitive conditions. Player discretion is advised.
Return to planet 4546B
Submerge yourself in an all-new, sub-zero expedition in an arctic region of Planet 4546B. Arriving with little more than your wits and some survival equipment, you set out to investigate what happened to your sister...
Uncover the truth
Alterra left in a hurry after a mysterious incident. Abandoned research stations dot the region. What happened to the scientists who lived and worked here? Logs, items, and databanks scattered among the debris paint a new picture of the incident. With limited resources, you must improvise to survive on your own.
Discover uncharted biomes
Swim beneath the blue-lit, arching expanses of Twisty Bridges. Become mesmerized by the glittering, mammoth crystals of the Crystal Caverns. Clamber up snow covered peaks and venture into the icy caves of Glacial Basin. Maneuver between erupting Thermal Vents to discover ancient alien artifacts. Below Zero presents entirely new environments for you to survive, study, and explore.
Construct habitats and vehicles
Survive the harsh climate by constructing extensive habitats, scavenging for resources, and crafting equipment. Blast across the snowy tundra on a Snowfox hoverbike. Cruise through enchanting and perilous biomes in your modular Seatruck.
Research alien lifeforms
Something undiscovered lurks around every corner. Swim through the giant Titan Holefish, encounter the haunting Shadow Leviathan, and visit the adorable Pengwings. Keep your wits about you. Not all creatures in this strange world are friendly.
Survive the chilly temperatures
Jump in, the water’s warm. The below zero temperatures of this arctic region pose a new threat. New weather conditions blanket above-ground habitats. Craft a toasty cold suit, sip on piping hot coffee, and warm up next to Thermal Lilies to stave off the chill.
An ocean of intrigue
What really happened to your sister? Who were the aliens who came here before? Why were they on this planet? Can we find solace from grief in truth? Below Zero extends the story of the Subnautica universe, diving deep into the mystery introduced in the original game.
About the development team
Below Zero is created by Unknown Worlds, a small studio that traces its roots back to the 2002 Half-Life mod Natural Selection. It is the same studio that created the original Subnautica. The team is scattered around the globe, from the United States to the United Kingdom, France, Russia, Austria, Australia, Canada, and many more places.
Warning
This game contains flashing lights that may make it unsuitable for people with photosensitive epilepsy or other photosensitive conditions. Player discretion is advised.
Are these done yet?
Last evaluated Jun 22, 2026
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