What we know
- The official Steam listing marks the game as Windows online co-op.
- The August 12 public-lobbies post reports Public, Friends Only, Invite Only, and Private modes.
- The launch FAQ and later lobby post both describe Steam-based invites; the later post supersedes the FAQ's older no-public-matchmaking statement.
Before you start
- The host and each joining player need access to the Steam release.
- Steam friends must be online for the Steam-friends invite route.
- The host must choose a lobby visibility mode that permits joining.
What to do
- 01
Choose Public if you want anyone to be able to find and join the lobby, according to the August 12 announcement.
- 02
Choose Friends Only to limit joining to Steam friends, then use the normal Steam invite flow.
- 03
Choose Invite Only and interact with an envelope on the lobby desk; the post reports an ‘Invite friends’ prompt.
- 04
Do not use Private when inviting: the same announcement says Private rejects joins and disables invites.
How to know it worked
- The invited player appears in the same lobby before the run starts.
- The chosen visibility mode matches who can enter the lobby.
If it does not work
- Invites are unavailable: Check that the lobby is not Private.
- A player does not join: Check the Steam friend state, expired invite, host closure, and later UI changes.