Feedback on the below would be helpful and appreciated:

 

A character has a multiform--a huge jaguar. After she transforms from a human into the jaguar, the jaguar personality takes over, which is sentient and loosely connected to the human character. So there is some loss of control, but she's not "Enraged." Like the Hulk in the recent Marvel movies, it's difficult for her to transform back into her human form. It's effortful and external factors can help to make it more likely (e.g., friends' encouragement). So, the idea is that she can change into the jaguar willingly, but it entails some risks--in terms of the personality change and the difficulty in transforming back into her human form.

 

 

I feel like this touches on a few different elements for constructing the phenomenon, but I'm struggling to put it all together. I'd value hearing how people might tackle this.

 

You've essentially spelled out what you need to purchase:  Multiform with the Personality Loss and Requires A Roll Limitations....Or just Personality Loss, which already entails some difficulty changing back.