i used the newest version of rftools (1.12-7.22) and mcjtylib (1.12-2.6.1).
So some mobs fall and go through the shield blocks. Examples are npc's from custom npc's, fox from drp medieval and some mobs from the avatar out of the iceberg mod (the fire and airbenders and skybison. The OtterPenguin does work as normal) mowziesmobs also but this was on 1.11.2 . i hope this examples can give you an idea what could cause this.

Anyways thanks for the time. I hope you can fix this.

Can you show me the configuration of your shield? Are you sure you set it to affect passive mobs?

its set to stop all entities. ill take a picture as soon as i get home

Screenshot of your shield config please

Hmm weird. I'll check it out

Can you post your whole mod list with versions? Are you using Sponge?

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