How to Join a Friend’s World in Core Keeper (Multiplayer and Crossplay)

To join a friend's world in Core Keeper multiplayer, ask the host for their Game ID, choose Join Game on the main menu and paste it in. Up to 8 players can play together on PC, PlayStation and Xbox (4 on Nintendo Switch), but crossplay only works between PC stores and within the same console family. Here's the full step-by-step, plus the limits and fixes worth knowing.

Good timing: Core Keeper has a free weekend on Steam from Thursday, October 8 to Monday, October 12, with the full game and online multiplayer, so friends can join you without buying it first. If they keep playing afterwards, their save stays in their library.

Core Keeper multiplayer at a glance

How do you host a Core Keeper multiplayer game?

1. Start or load the world you want to play in.
2. Press Esc (or open the pause menu) once you're in the world.
3. In the top-left corner, choose Copy Game ID.
4. Send the Game ID to your friends.

Your friends can only join while you're in the world, unless you run a dedicated server. Anyone with the ID can join, so only share it with people you want in your world. If you need a new ID, you can change it from the same menu.

How do you join a friend's world in Core Keeper?

1. On the main menu, choose Join Game.
2. Paste the host's ID into the Enter Game ID field.
3. Press Join and pick or create the character you want to play.

On Steam you can also skip the ID: if you're Steam friends with the host and they're online, they can invite you straight from the Steam friends list.

Does Core Keeper have crossplay?

Partly. Fireshine Games, the publisher, says Core Keeper "ONLY supports cross-play between PC platforms", using its PlayFab networking, so Steam players can join players on other PC stores. Consoles can play within their own family: PS5 with PS4, and Xbox Series X|S with Xbox One. PC and consoles can't play together, and Fireshine says there are currently no plans to add PC-to-console crossplay.

If you're on PC and your friend bought the game on a different store, both of you need to turn on cross-play in the gameplay settings, or you won't be able to connect.

How many players can play Core Keeper together?

Up to 8 players on PC, PS5, PS4, Xbox Series X|S and Xbox One, and up to 4 players on Nintendo Switch. Pugstorm says the difficulty scales depending on whether you're playing solo or as a team, so bigger groups face tougher enemies.

Image: Pugstorm / Fireshine Games

Why can't I join my friend in Core Keeper?

• The host isn't in the world: without a dedicated server, the host has to be playing for anyone to join.
• Different platforms: PC can't join consoles, and PlayStation can't join Xbox.
• Cross-play is off: on PC, both players need cross-play turned on if you bought the game on different stores.
• Wrong or old Game ID: copy it again from the host's pause menu, especially if they changed it.
• The world is full: it's 8 players at most (4 on Switch).
• Different game versions: make sure everyone has the latest update. Pugstorm released hotfix 1.3.0.6 on October 9, 2026.

Watch the Core Keeper trailer

The Void & Voltage update added the Breaker's Reach area and its Void sub-biome, and brought Core Keeper to Nintendo Switch 2.

More co-op survival games on iGame Magazine

• Core Keeper full release patch notes – what changed at 1.0
• Enshrouded 1.0 mage guide – another co-op survival crafter
• Palworld's Tides of Terraria update – more co-op survival building

Core Keeper multiplayer FAQ