[MC-54649] Non-Persistant Mobs Despawning On Exit

Endermen, Skeletons, Slimes at the minimum disappear on exit/save and reload.

Attachments

Video example.

could see it in your video, the zombie was going towards you, when you quit and reopen your world the zombie is gone

I have this behavior too in 14w19a.

Not sure which snapshot resolved this, but it is no longer an issue as of 14w25b.

I think was fixed in https://mojang.com/2014/05/minecraft-snapshot-14w20a/
Update: Snapshot 14w20b has been released to fix mobs not spawning naturally.
Anyway the bug vanished fast.