[She's grateful for the directions, seeing as she has no practical (and barely any theoretical) experience with fighting. R-]
Right. [Whatever these new powers are she feels more in control of them than her usual ice, even if her chest tightens at the thought of blasting magic at the bird with Arthur so close. She hesitates about attacking, and when Arthur throws himself back into the fight she slowly circles the two of them, waiting more for Arthur to move away from the creature than an opening in the bird's defense. What if she should hit him?
The opportunity presents itself when Arthur disengages after striking the spirit, leaving it screeching and trying to move away. She directs a blast of moonlight at it-- alone, it didn't do much good, but maybe in combination with Arthur's attack...]