A Railgun In Fairy Tail, Diablo Saga 7: Finale Part 1.

Armor La Rosé

"POWWWWWW!!!" Goku Black was thrown like a rag doll as Erza's  lance exploded into his chest with tremendous force.

Erza leapt into the air, her agility now seeming to increase by tenfold, swinging and slashing her giant lance with ease..

"POW POW POW POW POW!!" Blood flew, as Erza's points continued to go up, from 10 to 50 to 80.

"DAMN IT!!!" Goku Black roared, flashing away from Erza. "How dare you strike a god!!!"

"A god!?" said Erza. "You naive FOOOOLLL!!!" 

Erza hurled a haki powered kick straight into Goku Black's jaw, causing him to smash straight into the ground.

At the same time, Grimace came back to life, and launched himself at Goku Black this time, raising his sword for a tremendous blow.

"NO!!" Black stammered, barely managing to block the attack in time with a ki blade. But as the Diablo reverted into a statue, Erza slashed a winged hilted sword down at Black.. and he was forced to jump out of the way, blood dripping from his chin.

"This is impossible! I can't be defeated by a mere human!!" Black roared. "A mere human who ruins the entirety of creation!!!"

Black created two giant scythes made of his Super Saiyan Rose ki

He slashed them with great speed and malice, now matching strike for strike with Erza's power.

"Again, he grew stronger just from being beat up!" said Mikoto. "Damn, won't this guy quit!?"

Mikoto turned to look at the dazed Freya who was being treated by Chopper, she felt a tremendous rage just looking at this. How she longed to run into the field herself and help Erza beat the crap out of this Super Saiyan Pink Jackass..

But Erza wouldn't appreciate somebody interfering with her fight in such a way.

"All you filthy humans!!" Black roared, as he and Erza continued to exchange blows. "INFESTING this world.. destroying it.. turning it into a an abomination!!"

Black leapt back and pointed at Erza. "Mortals like YOU!!"

"I have no interest in your misguided ideals." said Erza. "But even the gods are not perfect. You yourself judge us mortals by only one standard, and in that, you become a man not fit to play the part of jury or guide!"

"How could you say that Erza Scarlet? Do you not know what I've done?! I've put myself in the body of a mortal.. a god.. me!" said Black. "Only the most benevolent god would do something similar to what I would do.. become a mortal for the sake of his flock.."

Erza's eyes narrowed. 

"Your Guild Master knows my pain better than any!!" Black exclaimed, pointing at Mikoto. "She was Fulguras, the Thunder Goddess, the Numensapien that stood at Supremos's side and watched over ALL.. the Lance of Gungnir.. and here she stands as a human, all because she took compassion on you mortals.. as did I!"

"You've made a big mistake now.." Erza growled. "You dare compare yourself to my guild master as if you are of the same crop? Tell me.. what kind of mercy have you shown today that slightly resembles what she would do!? Mikoto Misaka or Fulguras as you call her.. would never attack an bystander simply because they irritated her..  "

Black sighed. "It seems I cannot make you understand human.. I'll dismantle you myself.."

Black  raised his scythe. "I've grown even more powerful thanks to you.. all this power you've given me.. I shall use it to destroy you."