Hello, I am using the Improved Mobs mod on my server, which equips all mobs with all available armor and weapons, apparently there is a problem with the texture of the Necrotic Chainmail armor and the Mummy mob from the Rotten Creatures mod .

crash-2023-05-29_17.45.18-client.txt

I have checked and this seems to be a known issue with Rotten Creatures.
It seems that this will be fixed in the next Rotten Creatures update.
Reference: teamfusion/rottencreatures#23