Resolution: Awaiting Response
Affects Version/s: Minecraft 18w16a, Minecraft 18w21a, Minecraft 18w21b, Minecraft 18w22a, Minecraft 18w22c, Minecraft 1.13-pre1
Fix Version/s: None
When loading some chunks, that were previously generated, the server randomly crashed (a few times).
Restarting the server made the game continue as normal, so it doesn't happen multiple times for the same chunk.
There's nothing special in the chunks, just some colored terracotta and (infested) stone mainly; no entities.
Note: some other people seem to have a different NullPointerException ticking world crash with different class files:
Mod edit: Copied over from
When loading a 18w20c generated Buffet World (Warm Ocean) in newer snapshot 18w21a, a fatal NullPointerException occurs, causing the game to crash.
1. Download, extract and place in the saves folder the Minecraft world at http://www.mediafire.com/file/l189qh7bt163aqy/2018-05-23_14-35-40_New_World-.zip/file
2. In the playerdata folder for the save, rename the existing user.dat file to contain your Minecraft UUID (required for issue reproduction)
3. Launch snapshot 18w21a or newer
4. Select Single Player
5. Select the extracted world with your renamed player data file
6. When prompted, click the "I know what I'm doing" button
- Subsequent loads of the world will not generate error, only the first load of the 18w20c will cause the issue