Below Zero is an underwater adventure game set on an alien ocean world. It is a new chapter in the Subnautica universe, and is developed by Unknown Worlds.

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 being 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.

Open development
Subnautica: Below Zero development is open. Get weekly or daily updates, see what the development team is working on, view real time change logs, and give feedback from inside the game. We want to hear your thoughts and invite you to participate in what we are working on.

Warning
This game contains flashing lights that may make it unsuitable for people with photosensitive epilepsy or other photosensitive conditions. Player discretion is advised.

Key Features

• Return to Planet 4546B
• Explore new biomes & encounter all-new creatures
• Build your habitat for survival
• Survive the frigid elements
• Rich narrative that dives deeper into frozen mysteries

To activate the game, you need a Steam Account

• Login or register at the official
  Steam Website and download Steam client
• Install and start application, login with your Account name and Password
• Click the Games Menu.
• Choose Activate a Product on Steam...
• Follow the onscreen instructions to complete the process
• After the successful code verification, go to the "MY GAMES" tab and start downloading.