Raquel Casull gets hers right from the start, making an utter fool of a Mauser priest in the first episode: "Subjects of the flames, dance!" BOOM. Match is over before the other guy can get a shot off, and she does it two more times to add insult to injury. He probably should have learned a less powerful spell.
In the first light novel, she does the same thing to Big Shot when he attempts to kill Pacifica. As an added bonus, she uses her most powerful spell against him (Thor, which in the anime destroys the Mauser church she was in because she screwed up, but manifests as a lightning golem in the books) and sends the would-be assassin running for his life.