i started a drygmy farm and used 1 Drygmy charm in a mossy stone, the henge was formed and the drygmy worked fine! when i tryied to add a second Drygmy my world crashed and i can't re-join. the console gave this entries:

[Server thread/INFO] [minecraft/ServerGamePacketListenerImpl]: lost connection: Internal Exception: io.netty.handler.codec.EncoderException: Failed to encode packet 'clientbound/minecraft:set_entity_data'

versions:
MC-1.21.1
Neoforge-21.1.72
Ars versions-5.2.0
ars nouveau 5..0
ars additions 1.21.0-21.0.2
ars ocultas 2.0.1
ars elemental 0.7.0.7

Modpack: Allthemods10

the full log is in https://mclo.gs/xnkWx3X

This is a bug that I just ran across as well. The solution I found was to put each drygmy on their own henge then dispell them and then for me at least you can add them to the henge you want.

Also had this issue. On a server it kicked me but the server stayed up.

[Error] [minecraft/EntityStorage]: An Entity type entity.ars_nouveau.drygmy has thrown an exception trying to write state. It will not persist. Report this to the mod author

lmk if you need more info.

A fix for this was released a few days ago. Please update to the latest.

thanks a lot