User blog comment:Otaku Chick/Otabear's Anime Review: Ep 131/@comment-4829046-20120520102305/@comment-69.119.144.75-20120522014445

I think Mashima mentioning this arc in the manga means that A.) Mashima helped create this anime-only arc and its characters or B.) Mashima gave this arc the A-okay and wants everybody to consider the arc canon.