User blog comment:BlackWizardZeref/Fairy Tail Chapter 399: Wings of Despair Review/@comment-203.111.234.105-20140909162133/@comment-7418318-20140909220550

This isn't an argument of whether Erza is his most favourite character, but how she received much more favouritism than Mira or at least that's how I saw the first anon's post.

You ask when the last time was when an arc was about Erza? I ask you, when was the last time when an arc focussed on Mirajane?

You mentioned power-ups. Mira didn't get any power-up in this arc or EVER. Not unless you count re-activating her dormant powers. And Erza? At the very least she got 2nd origin.

Stealing part of Sayla's curse is what her magic is all about, so I don't count that as a power-up. Especially since it was only incomplete and temporary to begin with.