In MixinLivingEntity, you call this.getLootTable() and then perform operations on that.
getLootTable() can, and will, be null. This causes crashes if an overriding entity returns null.
See itsmeow/betteranimalsplus#255

Relevant lines: https://github.com/CorgiTaco/Mobifier/blob/86350edc39f8280717b23677b554ed5bb720ed25/src/main/java/corgitaco/mobifier/mixin/MixinLivingEntity.java#L36-L37