Since day 1 after release, multiplayer has been one of the most requested features. We've always shared that wish and have both spoken quite a bit about multiplayer so far, but also showed some things already.
Before we could fully make multiplayer, we wanted the base game to be really solid and nicely replayable. This was the intention of "A Keeper's Duty" update. We've been hard at work on the full multiplayer since then, and the release is now within sight.

Before I dive into what comes with multiplayer exactly, please enjoy the multiplayer trailer :)
Multiplayer encapsulates multiple things in our case:

• Cooperative Play
  
• Competitive Play
  
• Local Splitscreen
  
• Online Multiplayer

We've had cooperative splitscreen multiplayer playable since quite some time ago, but it was not ready to release. Usually in game development what feels like the last 20% of a feature takes 80% of the time, and here it was the same. It needed a lot more work.
In addition, I think online multiplayer is also really important for any multiplayer game. Needing to have your friends in your house to play with them would always limit how much you can play. The tricky thing is that adding online multiplayer to a game that already exists is really complicated and generally a thing that everyone heavily advises against.
We still did it!
So Dome Keeper will release multiplayer with a local splitscreen feature but also with online multiplayer. You can even combine that freely, like playing as two people on one machine in splitscreen with a third friend half a world away, as a 3 person team.

Lastly, I always saw a lot of potential in a competitive play where two teams, each with their own dome, sharing a single big mine, would compete against each other. The game did simply not support more than one dome or even more than one keeper on a map. This made things so much more complicated especially around the upgrades, as some of the upgrades count for all keepers of a team, some count for only the dome, some only for specific keepers and some even for the opposing team.
More on how this works in the Versus Mode section.

What's important to note is that we have not planned for public lobbies. You can join other people with join codes and if they are your friends on steam. So you know who you are playing with and both you and us do not need to worry about cheaters.

If you want to get more insight into the multiplayer journey since last year, check out Chris Ridenour's talk from GodotCon 2025, as he is the one leading the technical side of Dome Keeper multiplayer.
For me this is the most exciting mode because it is the biggest break from "regular" Dome Keeper. In short it is two teams of keepers, each with their own dome, being placed on a single large mine and trying to win against the other team.
Versus mode in split screen, 1 vs 1 in this case.Right now there are two win conditions which you can pick at the beginning:

1. Last Dome Standing: just outlive the other team.
   
2. First to make a large resource delivery.

We are open to more ideas for win conditions, so please share if you have an idea :)

You actually share one map with the other team. Note the bubbles on the top, which are the dome locations. Maps can also be mirrored.An important part of competetive play is that you can not only improve your team, but you can also actively sabotage the other team by spending resources and recovering relics. Usually you think about these three questions when upgrading:
- Do I need more mining power?
- Do I need more transportation capabilities?
- Do I need a better defense?
And with this two dome setup a new question gets added to the mix, making it much more interesting: can I spare resources to sabotage the other team? Of course you can also just fly over into their part of the mine and try to steal their resources, or kidnap their drillbert (if you are really evil 😤).

There are two ways to sabotage. The first is to buy upgrades that directly and permanently increase the strength of the wave the other team will face.
Simple upgrades to convert your precious resources into pain.The second is to unearth a relic, bring it back to the dome and choose a corruption which is a strong and permanent buff to the monsters that attack the other team.
Corruptions can be a game winner for you, if the other team is not prepared.

You can also play as teams, for example in a 4 versus 4, or even a 2 versus 5 if you like.
But wait, there is more! You can also pick some modifiers for the game during the loadout. These are not visible to the other team, so you can adjust your strategy to a modifier and gain an advantage over them. But of course they can do the same.
You can even have different difficulties between the teams, if you want to compensate for an experience or skill gap.In these modes, you can simply play the game cooperatively with other people. The domes comes with an additional weapon station, so up to two keepers can participate in combat. This is the same in versus mode.
Right now we are aiming for up to 8 players in these modes. We initially wanted to limit this to 4 players, but found that it's absolutely chaotic fun to go beyond that limit, even if it is quite unbalanced.
You can see a second battle station in a second cellar layer.We are still experimenting and balancing a bit here, how to make it fun and engaging across different player counts.

For prestige you can play with one more keeper in the modes you already know. These runs go into a separate multiplayer leaderboard. For our hardcore players this should be a lot of fun, because you'll want to find a great teammate but also experiment with different keeper setups. Maybe combining the strengths of the Engineer with the strengths of the Assessor is a great strategy? Or doubling down on the Assessor and combining the different skills of the Assessor?

The good news is that all of the four previously mentioned staples of multiplayer are now implemented and work as they should. What remains for us is to fix a lot of bugs, edge cases, crashes and improve the balance overall. We want to take enough time with this so you'll get a stable multiplayer on day 1 of the release, and not just a broken mess that is frustrating.
To ensure this, we will also do a big playtest on Steam, basically stress testing the multiplayer but also trying to find all the edge cases we can, and see if the balance is good. We'll do that once multiplayer is really stable, so keep an eye out for future announcements here.

When Dome Keeper releases on consoles, it would equally release with multiplayer. Again we put in a lot of effort to enable crossplay, so you could actually play with anyone who owns Dome Keeper. You can join their games by entering an invite code, similarly as you might know this from other games.
On one platform you can also easily join any of your platform-friends game.

We know it's been quite a long wait, but really we wanted to deliver something that has everything you can want from multiplayer and also offer something new that can only happen in multiplayer. I hope you can see that we put in maximum effort here :)