After update to latest geckolib , this issue still happened.

I find it's caused by different entities. ( on modpack server )
Can't reproduction in local world.

Appears randomly and is difficult to examine further.

Crash report here
https://gist.github.com/AngleNaris/0ffa6801fd3704357ee0527e01eb17b5

Alright

now isolate it down to the base mods that cause it
There's a lot of stuff happening in that pack

Same exact problem (Cannot invoke "net.minecraft.world.entity.Entity.m_142038_()" because "p_91315_" is null)
If you find any fix let me know!
(Already tried to update to the last version)

crash-2025-03-19_07.17.20-client.txt
crash-2025-03-19_07.29.45-client.txt

On my case its when I summon a drowned end he have any piece of armor!

now isolate it down to the base mods that cause it