I responded Dioxide.

@Calla: I'll tell you the same thing I told Dioxide to explain my reasoning:

"I understand that she doesn't have much control over her powers yet and I'm fine with strong emotions making her powers surge. However, they're all in a circular arena that's three miles wide and filled with grass, trees, and other foliage, and she's saying that she killed all of it at once, just to power some super storm.. Sue's pretty darn powerful, but even she was only able to affect a small portion of the Academy, and that's because Mimic's powers increased the effects exponentially."