The team behind Subnautica, the popular exploration and survival game, announced the development of a new, stand-alone expansion. Called Subnautica: Below Zero, developer Unknown Worlds Entertainment says it will take place in a polar region of the game world and include massive glaciers and icebergs.

Subnautica was released into Steam Early Access in 2014. Once there, it steadily built up a reputation as a challenging and immersive survival experience, for traditional PC players as well as those with virtual reality hardware. When the game begins, players find themselves crash-landed on an ocean world. They must scavenge from the wreckage of their starship and contend with an inhospitable alien landscape in order to stay alive.

Earlier this year, Subnautica exited early access. It’s gone on to receive critical acclaim, including placement in Polygon’s list of the best games of 2018 so far.

From our review:

Subnautica in 2018 is richer and more mysterious than I could have expected, a sprawling and playful experience that captures the thrill of survival and exploration games while largely trimming away the busy work that has accumulated on the genre like biofouling on the belly of a boat.

According to the announcement on Unknown Worlds’ official website, Below Zero will enter early access in the next few months.

“The concept of Below Zero is still developing,” it said. “We are keeping the core gameplay mechanics, such as base building and open-ended exploration. We are also exploring new ones, such as thermal management, and more voiced dialogue at the core of the plot. We’re still in early stages and nothing is set in ice.”

Fans can track the game’s development on Trello.