[MC-130964] Aquatic mobs spawn extremely rarely when upgrading from 18w16a

Aquatic mobs spawn extremely rarely on already generated chunks when updating worlds from 18w16a to pre-release 1 (1.13). Guardians are also affected!

Linked issues

is duplicated by 2

MC-131345 Mobs spawn extremely rarely when updating a map from 18w16a to 1.13-pre2 Resolved

MC-131447 Update map from 1.12.2 or earlier version makes guardian also spawn around the outside of Ocean Monument Resolved

relates to 2

MC-129725 All solid blocks can pass light when converting a world from 18w16a to 18w20 + Resolved

MC-129682 Hostile mobs don't spawn after upgrading from 18w16a Resolved

Attachments

Comments 5

kumasasa 2018-06-06T08:32:57Z

What happens when you load a pre-18w16 backup in 1.13-pre1 or when you recreate the world in 1.13-pre1 ?

Jason Chamberland 2018-06-06T11:14:06Z

Recreating the world in 1.13-pre1 fix the problem, mobs will spawn again, but everything build in the world in the snapshot 18w16a is gone. If I update my world from 18w16a to 1.13-pre1, only the chunks that I load in 18w16a will have this bug.

Greg Milson 2018-07-04T17:51:11Z

Affects 1.13-pre6

Asteraoth 2018-10-06T15:27:36Z

Is this still an issue in Minecraft 1.13.1?

Jason Chamberland 2018-10-08T06:45:02Z

No it has been fixed in 1.13.1.