User blog comment:IamJakuhoRaikoben/Chapter 388: Erza vs. Minerva, Review./@comment-77.195.192.29-20140613072638/@comment-184.3.65.133-20140613073742

Eh just b/c they're both Celestial Spirit Mages doesn't mean that they possess they same type of Magic Power if you get what I'm saying. There has to be something about Lucy that made her immune to Alegria and not just b/c she's a Celestial Spirit Mage.