https://bytebin.lucko.me/zuDYNfuAuP

https://github.com/MoriyaShiine/enchancement

I’m wondering if this is involved, given how it changes enchantments

Looks like it might be - I got the crash, though referencing a different enchantment. Good call.

https://gist.github.com/Lemonszz/bbbe44a6593c14ad894747e0d2025a2c

Relevant Enhancement issue MoriyaShiine/enchancement#6

https://aofpaste.com/tafedufofo.yaml
Another crash, from the AoF team.

So far, I'm unable to recreate this on my end.

I have a feeling some other mod is breaking quite badly and BM is being blamed due to the frequency the crashing code is being called.
In theory, if the crash is correct, the entirety of BM would be very broken, so I feel like some mod may be screwing with the registration process.

If anyone has any more information, please let me know!

Fixed on enchancement's end.