User blog comment:IamJakuhoRaikoben/Chapter 388: Erza vs. Minerva, Review./@comment-86.70.179.8-20140614135012

one thing made me laugh when i read this chapter, when Mard Geer speaks about the celestial spirit king, Erza doesn't react at all, and Minerva doesn't ask who is he, lol Mashima, a little plothole.

Personnally i think the arrival of Sabertooth was the only mean found by Mashima to make the two prophecies ( 12 keys and Frosch ) a reality, i bet he didn't remember write about them in the manga