This crash probably has to do with bewitchment's recent rewrite.

Crash report:

https://paste.dimdev.org/goluduseru.mccrash

Affected versions ("latest" is NOT a version):

• Minecraft: 1.12.2
• Forge: 14.23.5.2838
• AbyssalCraft Integration: 1.8.1
• AbyssalCraft: 1.9.10