UP TO FOUR PLAYERS. ONE ADVENTURE.

UNDERTALE CO-OP

Keep one launcher. Get new mod releases automatically when you open it.

DOWNLOAD WINDOWS LAUNCHER ↓
  1. Save the launcher somewhere easy to find, like your desktop.
  2. Open Steam, close Undertale, then double-click the launcher.
  3. In the game, choose CO-OP → HOST or JOIN.

Send your friend this page. Everyone uses the same launcher and needs their own installed Windows Steam copy of Undertale v1.08.

NOW AVAILABLE · r57

Original battles, now with full-body idle party characters and health bars at the side. Play with up to four people using the same permanent launcher.

Updates install between game sessions. If an update check is offline, your last verified installation is still available. Keep this launcher for future published releases.