Unknown Worlds is working on a standalone expansion for Subnautica and have given this expansion the name Below Zero. As you may guess the events in this will take place in a very cold environment, as well as after the main events of Subnautica. Below Zero is still early in development with the team stressing that things are likely to change, though much of the gameplay will be similar to Subnautica.
Unknown Worlds will be releasing a version of Below Zero in early access though that is still months away. However, fans can follow the progress of the expansion by going to the development team’s Trello board which shows everything they’re working on. Beware though as that area has unmarked spoilers due to it being one of the main hubs for development.
Source: Tags: Subnautica Below Zero