Per SP
Before version 5.8, AI monsters affected by Possession would cast a random skill against its allies, making this status very strong against AI.
But human monsters suffering Possession were able to choose freely which skill to cast, so they could "avoid" the Possession by casting recharge Stamina or harmless skills.
This doesn't seem something a real possessed Monster would do!
HOWEVER, I say if a real monster had an option for self preservation isn’t that what all his own instincts & skills are for ? Monsters have shields including possession blocking skills.

First, do not use all caps because that is against forum rules. Second please post in the appropriate area. Third do a search before posting, there are already several topics about the possession changes. Moving and locking your topic.