Subnautica 2 launched to massive success in mid‑May, racking up hundreds of thousands of concurrent players on Steam. Three months after launch, Unknown Worlds announced a new experimental build for the Early Access game, similar to what they did with the original Subnautica and Below Zero.

The experimental build is optionally available on both Steam and Xbox and lets players try upcoming content before it lands in the mainline build. The goal is to crowdsource issues and bugs before new features hit the main version, with players able to switch between builds without affecting their main savegame.

At the time of writing, the focus is on major updates; experimental players will receive them “shortly before” the main branch, though smaller patches may also be tested. Unknown Worlds warns of significant game‑breaking bugs and advises not to get attached to any saves while on this branch.

There is no way to import or export savegames between the experimental and mainline versions; they are stored in separate directories. Players should back up their saves whenever they switch. On Steam, each switch requires a small update; Xbox players download the full experimental build first, then only current‑version updates thereafter.