h3x
What ass pull?
The ass pull where Mami was shown magically having some power she's never had before. And that's on top of her knowing Homura was up to something and being paranoid enough to do something about it without even knowing what's up in the first place. That whole part of the movie ended up feeling really forced to me.
Oh, you mean her ribbons ability to create a clone of herself? Well, she can create from ribbons muskets and "tiro finale", so why not her clone doll? Maybe she improved in the time between the end of the series and the begining of the third movie? And it takes place in completely new timeline where who knows how stong now Mami is.