What steps will reproduce the problem?
I don’t know how to reproduce the bug, but it’s probably because there is some blocks at the highest altitude and mobs try to spawn above them (so at y = 256). Sadly, the error doesn’t show details about the event (location, mob type).
Nice catch, thanks very much. It's going through the isPrismarine check, that's a good hint for where to search. I'll check it out when I'm back at the computer.
Please paste the output from
/usb version
belowWhat steps will reproduce the problem? I don’t know how to reproduce the bug, but it’s probably because there is some blocks at the highest altitude and mobs try to spawn above them (so at y = 256). Sadly, the error doesn’t show details about the event (location, mob type).
If you have any log-files, please paste them to pastebin.com https://pastebin.com/uXCLdDJa
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