Do Breathedge or Subnautica have multiplayer?

Both are single-player only

Steam lists Breathedge and Subnautica the same way on this point: single-player only. source: Steam store page: Breathedge (RedRuins Softworks / HypeTrain Digital) source: Steam store page: Subnautica (Unknown Worlds Entertainment) Neither has an official online multiplayer mode, drop-in co-op, or split-screen. There is no shared save, no host-and-join, and no versus mode in the game as it ships. Whichever you choose, it is a solo journey by design, and both games lean into that: they are about your own isolation in a hostile place, whether that is a debris field in space or an alien ocean.

Why people expect co-op here

The confusion is understandable. The survival-crafting genre is full of co-op hits, so it is natural to assume any "crash, gather, build, survive" game lets you bring a friend. Breathedge and Subnautica sit in that genre mechanically but were both built as single-player stories, so the expectation simply does not carry over. If a guaranteed co-op experience is your priority, neither of these is the game to buy, and that is the honest answer rather than a maybe.

What about mods?

You may have seen mentions of unofficial, community-made attempts to add co-op to Subnautica. Anything like that is third-party, experimental, and not made or supported by the developer, so it sits outside what this site verifies and outside what you are paying for on the store page. We only make claims we can tie to a primary source, and the primary source here, Steam, says single-player for both. If official co-op ever ships, we will update this page against that source.

Common questions

Still deciding? See the full comparison, check how long each takes, or run the decision helper.