Multiplayer in Voidtrain supports up to four players in online co‑op. You can host a session from your save, make it visible to friends or everyone, and your crew can join via the in‑game browser or a direct Steam invite. If joining fails or the Session toggle won’t switch, relinking your Steam and Epic accounts and a few quick network checks usually solve it.
Co‑op basics (what you need to know)
Voidtrain uses direct online connections between players. One player hosts from an existing or new save. Sessions can be open to everyone or restricted to friends. Friends can join from the main menu’s server browser or by accepting a Steam invite while the host is in‑game. Cross‑play between Steam and Epic is available when accounts are linked in the game’s settings.
Host: Set “Is it an open server?” to “Only for friends” or “Yes.” “Only for friends” limits visibility to your Steam friends list; “Yes” makes it discoverable to anyone in the server browser. You can close the server later when you’re done.
Friend: From the main menu, select the option to find or join a game. Look for the host’s session in the list and join it. If the list is empty, refresh the list and confirm the host’s visibility setting.
Join friends with a Steam invite (reliable fallback)
Host: Right‑click your friend’s name and choose “Invite to Game.” Sending a direct invite often succeeds even when the in‑game browser doesn’t populate.
Friend: Accept the invite from the Steam overlay. If you get bounced back to the main menu after accepting, use the troubleshooting steps below and try again.
Open Voidtrain’s in‑game settings and locate the account linking section. Link your Steam and Epic accounts there to enable cross‑play discovery and joining.
If your Steam account was previously linked to Epic, unlink and then link it again. A fresh link resolves cases where the Session toggle won’t move off “No” and restores online functionality.
Link the accounts again from the same settings section. This refresh clears the state that blocks the Session visibility toggle and enables online join.
Add Voidtrain and Steam to your firewall’s allow list. If you still can’t connect, temporarily disable the firewall to test, then re‑enable and keep the allow rules.
If you use a third‑party antivirus, add exceptions for the game folder and Steam. If blocking persists, temporarily remove the antivirus, reboot, and rely on Windows Defender to test connectivity.
Remove conflicting network software and virtual adapters
Uninstall or fully exit VPNs, Hamachi‑style virtual LAN tools, and virtual network adapters from virtualization suites (e.g., VMware). These can interfere with direct peer connections.
Relaunch the game after verification. Host a fresh session and try joining once more.
As a rule of thumb, host a running session, set visibility to friends or public, and have teammates join via the server browser or a direct invite. If connections fail, relinking Steam/Epic and eliminating local blockers (firewall, antivirus, VPNs) usually gets you rolling.
