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.