Game initiates shutdown when trying to create a new world in SP with harvest festival installed B) https://minecraft.curseforge.com/projects/harvest-festival

Does only happen when OpenTerrainGenerator is installed, otherwise my pack runs smooth with HF.

https://gist.github.com/Beanius/5b3b2b6fb94afb0bad4a8039f0dc7c6b

this is the error i'm getting when the shutdown happens B)

edit: It's the same issue ruyanve reported: sun.reflect.generics.reflectiveObjects.NotImplementedException

Thanks for reporting this :)