Private lobby / Steam
Invite friends
Machine Party uses private online rooms for two to four players. The numeric room ID is the most dependable invitation method when the Steam overlay does not show a join action.
Host a private room, then send the long numeric room ID displayed in the lobby. Your friend enters it through Join Room. If Steam exposes an invite action after the lobby opens, you may use that instead.
Host instructions
Create and share a room
- Launch Machine Party through Steam and confirm Steam is in online mode.
- Choose the online host option and create a private room.
- Wait until the lobby is fully loaded and displays its numeric room ID.
- Copy the entire number. Avoid screenshots when possible; copied text is less likely to lose a digit.
- Send the ID privately to the friends joining this session.
- Wait until every subject appears in the lobby before starting the trial list.
A room ID identifies the current lobby, not your account. If the host leaves or recreates the room, the old number may stop working. Send the new ID rather than asking guests to retry an expired one.
Guest instructions
Join with the room ID
- Open Machine Party while Steam is online.
- Choose Join Room from the multiplayer menu.
- Paste or enter the complete ID with no spaces before or after it.
- Submit the ID and wait for the host lobby to load.
- If the game reports that the room cannot be found, confirm the host is still in that same lobby.
Everyone should be on the same current game build. After either Steam or Machine Party updates, restart the Steam client before debugging the network.
Steam overlay
Invite through your friends list
Create the in-game room before opening the overlay with Shift + Tab. Select a friend and look for an available game invitation or join option. Steam actions can depend on whether the current lobby is marked joinable, so opening the overlay from the main menu may not show the same choices.
If the invite action never appears, use the room ID. Do not keep rebuilding a working lobby simply because the overlay shortcut is absent.
Failed invitations
Why an invite may not work
- Expired room: the host left, crashed, or created another lobby.
- Different versions: one player has not downloaded the latest build.
- Steam offline: either the host or guest is shown offline or the client lost connection.
- Overlay disabled: Steam Overlay is disabled globally or for Machine Party.
- Privacy and visibility: Steam Game Details privacy can hide session information from friends.
- Copied character: a space or missing digit changed the numeric ID.
Test with one guest before inviting the entire group. That isolates lobby setup problems without four people repeating the same failed attempt.
The official Steam listing confirms online co-op for two to four players. Room behavior and invite recovery steps reflect the July 30 launch build and may change after multiplayer patches.