The game freezed for a moment as I was running through the caves. Suddenly the Lunar Grotto Biome spawned next to me at a random mud turf area instead of the usual location. All structures and mobs spawned at one point. I tried to regenerate the world but as I passed the area again, the error occurred anew.
I enclosed a Screenshot and the Client Log. Im not sure which MSMP-file to upload because there are 4 and they are all from 2020.