minecraft: 1.13.2
Forge: 1.13.2-209
mubble: Mubble-1.4-pre7-(1.13.2)

Describe the bug
created a new world with mod and game crashes

To Reproduce
Steps to reproduce the behavior:
1.create new world
2.start generating
3. See error

Expected behavior
Start a new world and have fun yayy

debug log:
debug.log

Hello there, have you tried downgrading your Forge version to 25.0.110? This is the recommended version to play in with Mubble at the moment, as said on the project page.

so many mods are asking for 191+

Thanks for the report!

However, this bug isn't a bug, in fact, this is a feature and properly works as intended.