Specific world crashes after loading, worlds crash when saving anyways

[freeneoprotogen]

Context

I updated my mods and a Sodium alpha release stopped my game from loading at all. After downgrading Sodium, I was able to load the game again. The problem now is that:

1. Whenever I save and quit a world, the game completely crashes. Crash report says "Description: mouseClicked event handler". World still saves.
2. Whenever I try and open the world I had before loading, the game just crashes. Every time I open it, I hear a horse sound (I think I was standing next to a horse), and then it takes a bit and crashes with "Description: Unexpected Error" and something about mixins.
   Crash reports for both are attached. Any questions will be answered.

Crash Report

https://mclo.gs/Za5t8aI and https://mclo.gs/SX8pSaA