User blog comment:Wrath022/Chapter 517: Wendy Belserion, Review/@comment-24489996-20170117142631

Though unrelated, it's something that's informative. Comes straight from one of my favorite tumblr blogs

--- You know what I’m starting to realize? Along with Erza’s trend of winning battles she can’t possibly win, and Natsu’s trend of always doing the same with the arc villain, there’s another part of the formula: Erza will always end up battling and taking out the strongest of whatever group of villains is subheading the arc villain.

You may notice how highlighted the problem of Erza winning duels she can’t possibly win becomes with this laid out the way it is. Aside from simply not being at all equipped to take on these enemies, Erza shares another Natsu problem: they both are the hero selected to win their respective duels over the heads of other candidates who not only are magically more on the opponent’s level, but have magic types much better suited to fighting them.


 * Jose is the big villain of the Phantom Lord Arc, but Erza takes out Aria, strongest of the Element 4, despite having been absolutely reamed by taking a blast from Jupiter. Natsu is taking on Gajeel, who while not the main villain, is the face of Phantom Lord.


 * Ikaruga is clearly the most threatening of Trinity Raven/Death’s Head Caucus, so Erza is the one who takes her on. Ikaruga’s powers are completely insurmountable and the only way Erza wins is by invoking a swords-clashing-duel where Ikaruga has the disadvantage. Heaven knows why.


 * Zero is the arc villain of the Nirvana arc, but of the Oracion Seis, Midnight is the strongest, so Erza dukes it out with him. One wonders whether Gray, who tends to take his clothes off, would be a better match for Midnight.


 * Faust and his Dorma Anim are the arc villain of the Edolas arc, but of the Edolas Royal Army, Erza Knightwalker is clearly the strongest, so Erza Scarlet takes her on. Mystogan, who is far above Erza’s level and has a lot of reasons to be fighting, is barely involved in the arc at all.


 * Azuma is the strongest (alongside Ultear) of the Seven Kin of Purgatory, so it is Erza who takes him out despite having no hope of victory. Gildarts is fighting Bluenote, who I have a heavy suspicion was introduced for the sole purpose of occupying him.


 * Cobra can safely be called the second most threatening of the Reborn Oracion Seis after Midnight, so Erza duels him.


 * Minerva who fills in the role as apparent strongest of Sabertooth, so it’s Erza who takes her out. Erza’s magic pool is not only extremely inferior to Minerva’s, but she is extremely unequipped to take on the person who can swap who is attacking who in an instant.


 * While not necessarily the strongest of the Nine Gates of Hell at base, Kyoka is their leader and her Etherious form’s power constantly rises without limit, ensuring she takes that title at some point–so it’s Erza who defeats her. Minerva, who can as mentioned swap who is attacking who, has a much better chance of defeating Kyoka, even when deprived of her senses.


 * Irene Belserion is the strongest of the Spriggan Twelve, and Zeref and Acnologia are already set to have a fight with E.N.D./Natsu at some point, so meanwhile, Irene is being taken on by Erza. Laxus, who has a much bigger magic pool and Fairy Law at his disposal, is out of the battle and Gildarts is being wasted on a God Serena Historia.

There you go, I’ve just made Fairy Tail conflict even more predictable than it already is. If there’s another arc after the Alvarez one, check back on this post, and see if this trend doesn’t continue, I bet you it will. ---

So yeah, it's a running trend here. To me, it's one of the few things that ruined FT completely.