An enchanted Prismarine Helmet from Minestuck will crash when the game tries to render it.
Crash report
Using NeoForge 21.1.187 for Minecraft 1.21.1, with GeckoLib 4.7.6, Minestuck 1.21.1-1.13.1.0 and Infiniverse 2.0.1.0
I think there's a null prevention check missing at this line