"Lightning......I........what are you doing?!"
The distress in her voice was clear as Rainbow, still on the ground, looked up and her former squad-mater, Lightning Dust. The green pegasus was flapping her wings, keeping above her rival, holding the element of loyalty which she had taken from Rainbow in the confusion of the tornado. She did not see what had happened to the other element-bearers, but it didn't matter. Because as long as just one of them was kept out of the fight, they couldn't use their elements.
"I'm doing what I have to."
Rainbow looked incredibly confused, and Lightning could not blame her. The last the two had even seen each other, it was back at the Wonderbolt Academy, when Lightning was kicked out. And even though Lightning had been keeping up-to-date with Rainbow's activities, the latter probably hadn't even given her a second thought, as evidenced by her continuing look of confusion.
"What do you mean what you have to? I need that element!"
Lightning looked to the golden necklace in her hoof and then turned back to Rainbow, frowning as she did so.
Rainbow said nothing, merely looked at the look of utter distain on Lightning’s face. It took a few moments, but Rainbow slowly began to understand. Lightning's continued holding of the element hindered their plan to thwart Sombra, so if she was refusing to surrender it, that could only mean one thing. Her expression of confusion slowly morphed into one of horror as she looked up and Lightning, hoping desperately that she was wrong.
Lightning waited for a few moments before slowly nodding, confirming Rainbow's fears. The rainbow-mane pegasus hung her mouth open with shock.
Then, a look of utter anger burst through and she spread out her wings in a threatening posture.
"YOU BETRAYED US ALL!!!"
Lightning narrowed her eyes at the angry mare.
"Yes. I did. And I don't have to explain myself to you or anypony else!"
Rainbow's frown deepened more.
"No explanation needed.....TRAITOR!!!"
Before Lightning could reply to that, Rainbow flapped her wings hard and launched herself into the air, straight towards Lightning. The latter did not react fast enough, and Rainbow soon collided with her, forcing her backwards. Although she'd been winded by the attack, she was clear-headed enough to saw that, as Rainbow was forcing her back, she was reaching for her element. Regaining her strength, Lightning pushed back, giving herself just enough space to be able to spin around fast enough to kicked Rainbow in the face with her hind legs as she attempted a second attack.
The green pegasus then flew higher up into the sky, with Rainbow in pursuit. Lightning knew that if she could just keep the element out of Rainbow's reach long enough, they would win. Looking behind her, she saw the very angry pegasus flapping even harder, catching up to her. But Lightning was not concerned. Even though Rainbow was undoubtedly one of the best fliers she'd ever known, she was better. And she would prove that today, not only to Rainbow, but to all of Canterlot.
The two flew faster and faster, oblivious to the raging war all around them. The sound of magical blasts and fights amongst the guards and changelings made it hard to hear, but that made little difference to the two of them. Lightning darted and weaved around the towers and spires of the city, hoping to shake Rainbow from her trail. But Rainbow kept up with ease. She'd clearly improved her flying ability in her time at the academy, much to Lightning's chagrin.
But then a smirk appeared on her face as a thought occurred to her. If Rainbow had improved, then perhaps it was time to show that she had too. One of the benefits of working for a guy like Sombra was that, with all the spells and magic at his disposal, he could make those who worked for him even stronger than before. Focusing on just such a strength, Lightning began to pick up speed, as Rainbow quickly noticed. She flew fast and faster until finally, she began to pierce the sound barrier. Rainbow's eyes widened with shock. She'd only ever seen that skill once, when she had done it herself.
But when the sound barrier broke for Lightning, it was not a multi-coloured rainbow effect, but a ring of bright yellow, like the colour of lightning itself. It sent shockwaves throughout, almost knocking Rainbow out of the sky. The young pegasus could not believe it, and was, needless to say, annoyed to no end that a talent of hers was now being used by a pony like Lightning. And so, she decided that it was time to fight fire with fire. She concentrated on her own sonic rainboom, which she had practiced many times now, and was soon breaking the sound barrier herself. A massive rainbow-coloured ring spread forth when she broke it, and soon she was hot on Lightning's tail once more.
The latter had no idea what Rainbow was catching up to her, perhaps unaware that her old rival had such a talent at her disposal. In fact, so much had Rainbow practiced this ability, that soon she was mere inches behind her. Rainbow knew that if she was going to catch up, this would be her only opportunity. She flapped her wings mightily and launched further forward, tackling Lightning from behind. The shocked mare could not react in time to this, and soon the two of them were plummeting out of the sky, grappling with each other in a bid to gain possession of the element. But soon their fight was brought to an abrupt end when they hit the ground.
The speed at which they'd hit it made it an unpleasant experience to say the least, but as both of them were students of the famed Wonderbolt academy, they'd both had training in dealing with quick recoveries, and thus they were both up and glaring at each other angrily in no time. Lightning still had the element in her hooves, but Rainbow made no move towards it. Without saying anything, both mares knew full well that they were on equal terms in their flying abilities, something that annoyed them both to no end. And so, Rainbow decided that perhaps it was time to resort to something she never thought she'd have to. Diplomacy.
"Why, Lightning? Why have you done all this?" She asked.
Lightning's frown deepen.
"You wouldn't understand. Nopony would!"
Rainbow could see something on Lighting's face. Embarrassment perhaps? Maybe even pain of some sort? Whatever it was, the pegasus could tell that there was something forcing Lightning to be doing this. Even though she'd only known her for a brief time, rainbow had come to understand that Lightning was not an evil pony. She could be selfish, uncaring for the safety of others, driven to the point of shutting out everything but her own success, but evil? Like Sombra? No. There was something else behind all this.
Rainbow took a step forward, causing Lightning to step back.
"Tell me. Let me help."
Lightning hesitated. She wanted to talk about this, but not to Rainbow. This was the mare who was responsible for her being cast out from the Wonderbolts. If there was one pony in all of Equestria she didn't want to reveal to, it was her. But as she looked at the understanding look on Rainbow's face, something changed. A need overtook her. A need to let out something she'd been wanting to let out for a very long time now. And so, against her better judgement, she spoke.
"I.......I wanted.......to be the best."
Rainbow tilted her head in confusion as Lightning continued.
"Ever since I was young.......since I was just a filly.....I have tried. I've tried to be the best flier. I've tried so hard over my life to win admiration. And the Wonderbolts.......they were my idols. I practically worshipped them. Everything I did, I did to impress them.......to be counted amongst them. And so I trained and practiced every hour of every day for my entire childhood. And then, when the time came for me to train under Spitfire herself, I could not have been happier."
Rainbow listened intently, and could not help but feel a sense of familiarity with this story. She too had trained hard over her life to impress the Wonderbolts and be one of them. But she knew there must have been more to it than that, so she carried on listening.
"But then.......YOU happened!" Lightning said angrily.
Rainbow had to fight the urge to take a step backward, given the threatening tone she'd said that.
"Because of you, I was cast out! Humiliated! Everything I'd worked for was destroyed because those I admire were too soft to accept that there are casualties in the road to greatness. And YOU...... you fed that weakness with your friends!"
Suddenly, something clicked in Rainbow's mind. During their time at the academy, Rainbow had often discussed with Lightning about all of her friends, about Twilight and the others. But, now that she thought about it, she couldn't remember Lightning having spoken of any friends of her own. Could it be that, perhaps, she had none? That her insatiable quest to improve herself had driven away what friends she had before? Rainbow shuddered at the prospect that, had she too become so driven, this could have been her betraying Equestria, instead of Lightning.
"After that....I had nothing! My dreams had been taken from me, and my one chance to achieve great things had been stolen! THAT is why I'm doing this Rainbow! I will prove to all of Equestria, to you, to the Wonderbolts, that I am the best!"
Lightning took another angry step forward. Rainbow had no doubt that she would attack her soon, and raised her hooves in an attempt to calm her down.
"Lightning! Listen to me! You don't have to do this! You could be great even without Sombra! Without the Wonderbolts even! You don't want THIS!"
Lighting frowned again.
"Don't you dare tell me what I want! I want ponies to look up at me and see somepony to aspire to! I want to be known far and wide as a mare of talent! I want....."
But, before she could finish, a loud explosion from far off distracted the two. They turned to see that, at the other and of the street from them, a tower had been assaulted by dozens of changeling drones. It was being swarmed all over, and the unicorn guards posted on it were simply overwhelmed by their numbers. The drones had attacked the foundations of the tower, and soon, it was beginning to crumble. Lightning and Rainbow looked on in horror as the unicorn guard screamed out for somepony to help them as the tower collapsed.
The two did not see what happened to them, as they were consumed by the dust cloud caused by the collapse. The two stood in silence at the sight of such destruction, before Rainbow turned to Lightning with an angry look on her face.
Lightning turned to face her as she angrily pointed to the rubble of what was once the tower.
".......did you want THIS?!"
Lightning, as she had done many times now, felt a sharp pang of doubt and guilt over what she had just witness. She looked from the wreckage of the tower, back to Rainbow's angry expression, before finally laying eyes on the element of loyalty in her hooves. And, for the first time in her entire life, she didn't know what to do.