random `NoClassDefFound` error

[HyperCodec]

I was just wondering around in my world and my game hung and then crashed. Here's the log: https://mclo.gs/wyaQS7C (sorry this is a pretty big modpack).

This same crash has happened in other modpacks, I suspect there might be a compatibility issue with arphex (even though their own mod suggests to add Nyf's spiders). It could potentially also be a conflict with some of the AI modification mods here, however in the other packs where it crashed I didn't have the same AI modification mods. It could be a conflict with spider AI modification in general.

[HyperCodec]

It appears to happen consistently now ever since I enabled Enhanced AI. Removing that mod doesn't entirely stop the crash, but it becomes a lot less likely to happen. Removing Nyf's Spiders appears to prevent the crash entirely.