Unknown Worlds has made no secret of the fact that it's been working on an expansion to the undersea survival game Subnautica, and has even shared some info on what's coming, including (via the Subnautica Wiki) an Arctic setting and an orbital station. Today it finally made everything official with the announcement of Subnautica: Below Zero, a standalone story that takes place in a new region of planet 4546B after the events of the original game.
That's the good news. The bad news is that aside from some concept art, the announcement doesn't tell us much that we didn't already know—mainly because there's still not much to see.
"The concept of Below Zero is still developing. We are keeping the core gameplay mechanics, such as base building and open-ended exploration," the site says. "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."
The site does hint at what's coming in Below Zero. The presence of an orbital station, "designed to provide a sustainable environment for research personnel stationed far from Federation space," indicates that this visit to 4546B is more intentional (and hopefully better equipped) than the previous trip, and a quote attributed to an "unknown Alterra employee"—that's the company you were working for when you crashed on the planet the first time around—suggests that you'll be digging deeper into some of the mysteries you brushed up against in the first game.
Unknown Worlds has previously said that the Subnautica expansion would go into early access release later this year, with full launch coming sometime in 2019, but no mention of that timeline is made on the Below Zero page. "In the coming months, we will release an unfinished, early version of Below Zero in Early Access," it says. "We will then begin releasing consistent content updates, carefully crafting the game based on your feedback—just like the original Subnautica."
The Subnautica: Below Zero concept art is... below.