Fix Kotlin Library Crashes in Your Modpack

Identify the Problem

If your game crashes on startup with errors mentioning Kotlin or Forgelin, you likely have outdated Kotlin libraries. This happens when mods depend on the original Shadowfacts' Forgelin but your setup uses newer mod versions.

Resolve the Conflict

1. Navigate to your mods folder

2. Search for and delete any file named Forgelin or Shadowfacts-Forgelin (the old version)

3. Ensure Forgelin-Continuous is in your mods folder

4. Launch the game

Forgelin-Continuous automatically provides the updated Kotlin libraries that newer mods expect. Removing the old file prevents both versions from competing, which causes crashes.

Verify Success

If your Kotlin-dependent mods now load without errors, the fix worked. If crashes persist, check your launcher's log file for other missing dependencies—you may need LibrarianLib-Continuous as well.