From that day forth, Aatrox was never seen again, or at least, neither side lived to tell the tale. The mane 6 fizzled out, their immense power unsustainable, and they returned to their normal state of being moments after Aatrox's departure. Though they could never truly forgive themselves for what they had done, they all agreed to never speak of it again, locking up the painful memories inside mental vaults. Twilight was eventually coaxed into telling Princess Celestia about what Aatrox had done to them, and while Celestia was horrified, she silently thanked him for protecting them, and keeping them safe, even if his way of doing so was less than agreeable.
Legends of a graceful sword master circulated Equestria for centuries to come, never truly dying out. Some versions told of a demonic alicorn, wreathed in a red glow, his mane flowing lava, his armor a part of him. Other tales were closer to the truth, telling of a giant with a living sword, feasting on the agony and bloodshed of his destruction. Whatever legends there were, none were closer to the truth than the one Celestia knew.
Despite her disgust and repulsion of Aatrox's methods, he did save Canterlot, if only as a side effect of his lust for battle. Celestia had a stained glass window pane made up of Aatrox, depicting his sword sucking in the blood of an army of changelings, as he lodged it in Chrysalis' neck. The stylized pane was much less graphic than one might think, but even then, it got the gruesome message across just fine. Celestia, having decided to try and forget about the incident, stored the pane away in her own room, where no one else might look on. She had taken some liberties with Aatrox's appearance however, converting his dark and foreboding look to a much lighter one, more prestigious and noble. She had taken the design for Aatrox's look from her very own Justicar Royal Guards.
She hoped with all of her heart, that he would never return, trying to lock away the brief memories she had of him. Yet she couldn't bring herself to forget about her unlikely savior. The pane reminded her every night of the swift , brutal justice he brought to bear against the changelings. She shivered at the thought of having to oppose such a merciless and sadistic killer. She still kept the parchment that had floated down from the sky after his departure in a stand by her bed, the depressing words gnawing at her every day. She wanted to forget it all, but she knew she couldn't.
So there the commemorative window pane sat for months, years even, forever reminding her of the Darkin Blade, until one day, she revisited it, not with a mix of disgust and gratefulness, but instead desperate hope.
Sometimes, when faced with a great evil, the only solution is an even greater one.
"A-Aatrox... I" , Celestia tried to stammer out her sentence, kneeling before the window pane, her drained and greyish form deprived of all her magic. She could hear heavy steps thundering down the hall. She had just transferred all of her magic into her most faithful student, and was weak, tired, and afraid. She looked at her flank in despair, bare and without a cutie mark, before turning back to the pane.
"Aatrox, I need ... " she considered not continuing, biting her lip as the thunderous steps got louder, and shook the earth beneath her. She closed her eyes, and sobbed softly, the tears flowing down her cheeks as a loud crack resonated throughout the palace. The doors to the throne room had been smashed apart, and only now did she realize that there was no other way. Twilight might be able to master the alicorn magic she had been given, but the real question was, would she be able to in time?
"WHERE IS SHE?!" , a deep, menacing voice boomed from the other room as he lifted Cadance and Luna up with his dark magic, attempting to suck out their magic, the loud, swirling noise frightening Celestia, sending a chill down her spine. Celestia was out of time, out of magic, and out of options. She had to do it. She leaned against the pane, desperately hoping her call for help would be answered.
"Aatrox ... I need you."