Barotrauma's free Companion Update arrives on 26 November, a week before the paid Home & Harbor Expansion on 2 December. It's a base-game update, so every Barotrauma server needs updating that day, whether or not anyone on it buys the DLC. FakeFish hasn't announced a release time yet, and a security patch (v1.13.5.0, released 27 October) is already out and worth installing first.
What's in the update
FakeFish describes the update as the groundwork the expansion runs on: it arrives "shortly before the DLC, on November 26, to establish the systems that the expansion needs to function together with the main game". A good part of it is new content for players who never buy Home & Harbor.
A new plugin system for code mods
The biggest change under the hood. In FakeFish's words, "the DLC functions as a code mod, and the Companion Update adds a new plugin system that makes code modding much more accessible."
So Home & Harbor itself is built on the same plugin system that modders get on 26 November. FakeFish hasn't published documentation for it yet, and hasn't said what it means for existing code mods (see the FAQ).
DLC systems that reach the base game
Several of the expansion's systems arrive in a partial form for everyone. The blog lists them: "Many of the DLC systems, such as dismemberment and prosthetics, advanced gardening and decoration, and a more lively world, are partially available in the basegame through the Companion Update."
The update also brings, in FakeFish's own caption, "new farming and shipyard modules", which fits the advanced gardening line above. The studio hasn't said how much of each system stays exclusive to the DLC.
A new transport submarine
The update "adds a new transport submarine" to the base game. FakeFish hasn't named it. The Descendant transport shown in the same post (the Vulgar Display of Logistical Supremacy) belongs to the expansion's new faction, so don't assume they're the same ship.
Networking fixes
The update brings "several optimizations and fixes to long-standing networking issues ("missing entity", begone!)." FakeFish hasn't listed the individual fixes yet, so read the patch notes on the day.
FakeFish hasn't mentioned any change to ports, server settings or the save format, so there's nothing to reconfigure ahead of time.
What your server needs to do
- Install v1.13.5.0 now. Released on 27 October, it fixes multiplayer exploits that let modified clients freeze the server, bypass its DoS filter to get other players kicked or banned, and "send the server data that would corrupt the campaign save the next time the game is saved". It also turns off crossplay through Epic Online Services, because Barotrauma has been removed from the Epic Games Store.
- Back up your campaign saves before 26 November. A big update is the moment to have a copy you can roll back to, even though nothing in the announcement points to a wipe.
- Update on 26 November, as soon as the update is out. Players' clients update through Steam, and a server left on the old version is one they'll struggle to join.
- Hold code mods until their authors confirm them. A new plugin system is the usual point where existing code mods need updating. FakeFish hasn't said older ones break, so check each mod's Workshop page on the day rather than assuming either way.
Running your own dedicated server? It's a separate, free tool on Steam (app 1026340), installed anonymously:
steamcmd +login anonymous +app_update 1026340 validate +quit
Tip: On a LOW.MS server, the Game updates card on the Overview tab shows when an update is waiting, and its Update button installs it (the server stops and restarts on its own). Take a copy first with Create backup on the Backups tab. Your campaign saves are in config/saves/ on the Files tab if you'd rather download them yourself. Need a server for the update? See Barotrauma server hosting.
What's coming next
- 26 November: the Companion Update, free for everyone who owns Barotrauma. No release time yet.
- Before 2 December: FakeFish says it will "go into more detail about all the new content in Home & Harbor in additional blog posts over the next few weeks".
- 2 December: the Home & Harbor Expansion, a paid DLC on Steam, adding player-owned outposts and the Descendants faction.
FAQ
Do players need Home & Harbor to get the Companion Update? No. It's a free base-game update, and FakeFish says it brings "new content for everyone".
Will the Companion Update wipe my campaign? FakeFish hasn't said anything about saves either way, and the announcement doesn't mention a wipe. Back up before 26 November anyway, so you can roll back if a save misbehaves.
What time does the update go live? Not announced yet. FakeFish has given the date only.
Will my mods break? Possibly, for code mods. The update adds a new plugin system for code mods, but FakeFish hasn't said that existing mods stop working. Check each mod's Workshop page for an update note on the day.
Does crossplay with Epic Games Store players still work? No. Patch v1.13.5.0 turned off crossplay through Epic Online Services after the game's removal from the Epic Games Store.
Sources: FakeFish: Home & Harbor DLC coming on December 2, Steam: Home & Harbor DLC coming on December 2, Steam: Patch v1.13.5.0.