Sorry if this isn't the right place to put this, but I was wondering if there was a way to prevent certain mobs from existing in your claimed chunks. Say I really hated bats for some reason and I wanted to make it so that no bats could spawn, and any that wandered into my claimed chunks automatically were deleted. What I'm trying to do is make the Burnt mod work with OPaC. Currently, fire still spreads in claimed chunks even if fire protection is turned on. I'm not entirely sure how it works, but it seems that Burnt uses entities to spread fire, so I'm hoping that if I can disable those certain entities (while still allowing other mobs to spawn and exist in my claims), I can disable fire spread in the claimed chunks. Thanks for the help!

You can prevent specific entities from entering your claim using a custom barrier group. But you can only prevent spawning for friendly and/or hostile mobs, not anything specific. Added it to the issue tracker though: #709