Published May 2, 2026, 11:01 AM EDT Co-op multiplayer is a big part of what defines the sequel Subnautica 2 devs brought back an axed feature from the first game Image: Unknown Worlds Entertainment/Krafton Sign in to your Polygon.com account What does it mean to be a Subnautica game? That’s the question developer Unknown Worlds had to answer when starting work on Subnautica 2 , which will be released on May 14 in early access after a messy pre-release period that included a much-talked-about delay . “I think for us, it was making sure that we had a really cool underwater alien world to explore that had surprises for people,” game design lead Anthony Gallegos told Polygon recently over a video call. “We could set it on the same planet again, but I feel like we've started to make that planet maybe not as surprising at this point.” Though Subnautica 2 has the number two in the title, it’s technically the third game in the series.…