User blog comment:BlackWizardZeref/Fairy Tail Chapter 399: Wings of Despair Review/@comment-203.111.234.105-20140909162133/@comment-178.148.165.225-20140909223044

Mira is a side character so it's only natural for her to not get an entire arc dedicated to her, but Erza is the only main character so far that doesn't have two and also Mira got a mini arc while, by the way things are going, Erza might not even get that much. Mira may not have got a literal power up, but she controlled those tentacle things, something we didn't even know she can do in the first place, so that's kinda like a power up.