"Quick, go to him while you still have a chance," Twilight Sparkle said quietly. She glanced around, but none of the remaining changelings in the room seemed to have noticed her freeing the princess.
Cadance quickly nodded in agreement, and started to stealthily inch her way towards her beloved. Thankfully the changeling queen was too busy laughing at the havoc in the streets below to pay her any attention. Cadance had never thought that she'd be grateful for ponies fleeing in terror, but it was at least giving her the chance to go unnoticed for now. After a few tense moments, she reached Shining Armour at last. He was still completely lost to the magical domination that had robbed him of his wits. When Cadance looked into his eyes, there was nopony there to look back at her.
What good will one last embrace do before the end? she thought bitterly to herself, as tears began to fall freely. He won't even notice that I'm here, and that would just hurt far too much... It had been bad enough when she'd been forced to watch him, and that mule-of-a-changeling Chrysalis, all throughout her confinement in the caves. To do so now, with Shining Armour finally within hoof's reach, and yet him have not even the slightest idea of her presence would just be cruelty incarnate. She stopped and turned back her attention to Chrysalis. Then that, that monster will have won, and there would be nothing anypony could do about it.
Princess Celestia was suspended from the ceiling inside a giant cocoon that was doing Discord-knows-what to her, the bearers of the Elements of Harmony were defeated, the royal guard had been useless, and Princess Luna was nowhere to be found. The shining city of Canterlot would be no more. In its place would be a blasted hive, where ponies were nothing but food to their changeling masters. Like a tumour, the infection would spread, until all of Equestria would be covered in so much muck, ruin and despair.
Then there is still a princess free now, isn't there? Cadance realised. While she had once been a pegasus, she did have now some of an earth pony’s strength thanks to her ascension. Without any kind of training to use that strength effectively though, Cadance couldn’t imagine any scenario where she could actually beat Chrysalis into submission with it. If she could cast combat magic like Twilight Sparkle, then she’d have been able to escape the caves without needing her help, and clearly Twilight’s magic hadn’t been enough anyway in the face of the changeling horde. So what else can I do? she thought desperately.
Her eyes opened wide, as a desperate plan began to form in Cadance's mind. There was just no other option. For Equestria to remain free, sacrifices would have to be made. Shining Armour was a soldier after all. Cadance was sure that he'd understand that. She just wished there could have been another way, or at least obtained his consent for what she was about to do. She fixed the sight of her one true love, along with her hated adversary for that love into her mind, and started to channel magical power through her horn. It was the oldest spell that she knew, but she'd never tried anything like this with it before, and especially not with herself as one of its targets.
"What!" Chrysalis yelled, spinning as she heard the crackling energy build-up forming behind her. "What do you think you are doing?"
Cracks were beginning to spread out across the stone floor under Cadance's hooves as the energy of the spell built up around her. Twilight and her friends hurriedly backed away from the mounting power that was spraying sparks of pure magic all over the place. On the tip of Cadance's horn a point of light grew in intensity that drew the eyes of everypony and changeling in the room.
"Stop, I demand it!" Chrysalis screeched. "I've won, don't you understand that yet?" She began to channel the same spell that she'd used to such effect on Princess Celestia. Several changelings hissed and snarled, then launched themselves viciously at Cadance, seeing her as a possible threat to their queen.
Before Chrysalis could let her stolen magic loose, an incandescent pink light burst forth and outwards from Cadance. The beams found their target in the horns of both Chrysalis and Shining Armour, where they split once more forming a triangle linking the three in an aura of power. The first two changelings that hit the aura crumpled against its immovable force. They fell backwards, completely dazed by the brutal and very unexpected impact.
"Twilight, what the hay is goin' on?" Applejack had to yell to make herself heard over the spell.
“I... I don't know!” Twilight could only stare as her brother's and the changeling queen's eyes opened wider seemingly than what was physically possible. Their pupils had disappeared entirely, replaced by a pink blankness that seemed to writhe and whirl, as she watched.
For several moments Princess Cadance, Shining Armour and Queen Chrysalis were linked in the spell's embrace, and then without warning, the beams dispersed. The energy broke apart and drifted away into a million tiny pink hearts. They were blown out over the city below before fading entirely.
Twilight Sparkle reacted first, running to the side of her brother who had collapsed after the spell had done whatever it was that it had done. Her brow creased, as she started to go through the possibilities in her mind, while she started to help her brother up from where he had fallen. His pupils were back to normal, but she could feel the lingering magic all over him. Whatever it was, she was sure she'd be able to figure it out though.
Chrysalis staggered backwards until she was pressed up right against the balcony. She shook her head to try to shift the thoughts and feelings that were darting through her mind like a multitude of tiny remorseless fireflies. She glanced at Cadance and placed a forehoof against the top of the balcony in an attempt to steady herself.
Cadance smiled back at her, causing the changeling to almost collapse entirely in on herself. Cadance tried to process what exactly what she was feeling for real and what was due to her spell, and then metaphorically shrugged her wings; working all that out could wait till later. For now there were far more important matters to attend to. "Please, Chrysalis," she said, her voice still weak from the toll that her spell had cost her. "End this."
"I..." Chrysalis stammered, seemingly entirely lost for the moment in Cadance's gaze. She shook herself once more, and looked around at the other changelings in the room, who were milling about and unsure of what to do. "You, you and you, go out into the city and tell every changeling to stop what they're doing. You two," she glanced at the pair who had been flanking Shining Armour, "do the same for any in the palace itself. Absolutely nopony is to be harmed or fed upon from this moment on, understand? You will gather the hive and wait for my command in the caves beneath the mountain. Swarm lord," she turned to a bulkier changeling clad in armour that stood taller than the other drones, "you will free Celestia and then find somewhere unobtrusive to wait to attend me."
The changeling lord looked like he wanted to challenge his queen for a moment, and then nodded, fluttered up to the cocoon upon his bug-like wings, and started to rip large chunks of sticky goop away onto the floor below.
"I'm so sorry for what I've put you through," Chrysalis said, glancing out down to the streets below where things were beginning to quiet down. "I don't know what I was thinking, when I went after him instead of you from the start, but now." Chrysalis smiled warmly at Cadance, revealing a whole lot of fangs in the process. "Now we can truly be together." Sickly eldritch energy washed over the queen, removing black chitin and replacing it with white fur. Moments later a new mare stood in the changeling's place.
"Oh my," Fluttershy breathed quietly, at the sight of the decidedly attractive mare shaking her new blue mane out. She was slightly smaller than even Twilight Sparkle, though had a far more toned and athletic figure, while yet remaining unfeasibly cute.
Twilight Sparkle looked up from her still completely insensible brother, to what could have been her brother's twin sister, that she knew full well that they didn't in fact have, and gritted her teeth hard. "Oh you have got to be kidding me..."
"You can call me Gleaming Shield if you like," the new mare whispered huskily, as she advanced on Cadance.
"Darlings, we don't seem to be in danger anymore, so would it be terribly gauche of me to drool?" Rarity asked. With the exception of the changeling lord who had paused in dismantling the cocoon to facehoof, Pinkie Pie who was laughing so hard she might sprain something, and Rainbow Dash who just looked puzzled, everypony else was ignoring her to stare for one reason or another. "I'll just go right ahead then," she added quietly, as nopony was paying her attention anyway.
"Oh my," muttered Applejack under her breath. She'd lived a life of totally unblemished heterosexuality up to this point, but 'Gleaming Shield' was making a great case for some flexibility on that viewpoint. She fanned herself with her hat and tried to think about the sight of Granny Smith on bath-day.
"Now that just isn't right," Spike reckoned out loud, from the statue he'd taken refuge behind. Seeing a mare version of the stallion he'd always looked up to and respected was odd enough, but that she possibly had an even nicer coat than his beloved lady Rarity, now that was just unacceptable. "Changelings really are evil," he said to himself.
"Is there any chance you would come away with me if I asked, even after all I have done?" Gleaming Shield said, after pausing in front of Cadance. "I would make you a queen."
Cadance leaned down and lightly nuzzled the smaller unicorn mare. She was inwardly amazed that she'd done it entirely without hesitation, intellectually at least, given she knew what this mare truly was beneath the pretty guise, and exactly what she had done. No repressed shudders of revulsion, no urge to wince all over, not even the imminent desire to turn tail and flee. It had been... nice in fact. She inadvertently glanced at the real Shining Armour, and refused point-blank to compare the new feelings this changeling was inspiring in her. Still looking at him reminded her exactly how wrong being with this affectation truly was.
She took a reluctant step back, and said, "Not now, my love. Now you must please change back to your true self. For me."
"Did Cadance really just say what I think I just heard her say?" Rainbow Dash asked Pinkie, who nodded in answer and then started to giggle even harder than she had been. Dash shook her head. "As if this day couldn't get any more random." She sighed.
"What do you reckon Twilight would do if I threw her a 'Happy-finding-out-about-your-sister-that-you-also-totally-failed-to-mention-along-with-your-big-brother' party?" Pinkie finally stopped giggling long enough to ask.
"I'd say it was nice knowing you, Pinkie" Dash replied, rolling her eyes.
"I have had a good run anyway," Pinkie Pie mused sagely.
Chrysalis swayed after hearing Cadance's words, almost seemingly several sheets to the wind on hard apple cider for a moment, and then nodded. There was another flash of green magic and Chrysalis stood once more next to Cadance. "Sho what'sss," she slurred, still high as a kite on the effects of the new freely given love pumping through her body. "So what's," she managed to say, after trying again to compose her words and stand a bit more steadily, "going to happen with us now?"
"I toss your rotten hide out of Canterlot," said a shaky voice from behind them. Shining Armour had a hoof propped over his sister's shoulder and was just about standing up. Then he noticed Cadance and slid off soundlessly back into a heap on the floor. "Twily please," he just about managed to croak out, "just what in all of Tartaurus is that pink horror?"
"Brother, that's Princess Cadance," said Twilight quickly. "You're supposed to be marrying her today, remember?"
"Marrying?" He grimaced, as a fresh wave of pain washed over him. "I was marrying Cadance, wasn't I?" His voice was getting stronger. "But Cadance wasn't real, Twily, I know that now. She did something to my mind which meant I couldn't see her for what she was."
"That's right," Twilight said, employing her practised younger-sister-knows-best smile. "I did try to tell you, remember."
"Yeah," Shining ruefully acknowledged. "You did, but that's a monster or something that must have slithered its way out of the Everfree forest. Can't you see it over there, Twily? It's vile... Save yourself, before they get you too!"
"It's Cadance! You must remember her!" Twilight insisted. "She used to foalsit for me, so you've known her for years now."
Shining Armour looked uncertain for a moment, then visibly winced again in horror as he caught sight of his former beloved out of the corner of his eye. "Won't let them touch you," he muttered.
Twilight jumped up, glaring daggers at the princess. "Cadance, just what in Equestria did you do to him?"
Chrysalis stomped forward, getting right between the two ponies, but a gentle touch of a pink wing pulled her back. "What I had to," Cadance replied softly. She looked down at the stone floor, not yet wanting to meet Twilight's accusing eyes.
There was something between the sound of a thump and a splat, as the cocoon finally parted. After a heavy, but somewhat squishy landing, Princess Celestia hauled herself onto her hooves. The changeling lord took one look at the expression on her face and promptly vanished as fast as his shimmering wings could carry him. The alicorn of the sun twitched violently all over, as she shook the foul changeling fluids off that caked her usually pristine body. Her horn flashed orange and she stood renewed once more, though now accompanied by the reeking smell of burnt ashes. Her hooves tapped out a little dance as she composed herself and mentally banished the feeling that she had been drowning, covered in spiders, worms and a thousand other nasty crawling things.
"You will pay for what you have done, changeling," Celestia hissed, as her horn ignited in cleansing fire. Her wings were still twitching, as the sensations of that cocoon were proving tricky to entirely shake off.
Gone was the normally serene, benevolent ruler that the ponies in the room had known. This was the Lightbringer Ascendant who stalked forward, leaving flaming hoofprints that glowed on the stone floor and left cinders where carpet had been.
It was Cadance this time that stepped forward, placing herself between Celestia and Chrysalis. "It is over, Princess."
"I..." Chrysalis drew herself up, gazing at Cadance's behind for the strength to do what she knew she now had to do. "I unconditionally surrender, and will do whatever I can to make things right."
The Lightbringer Ascendant paused, and Princess Celestia raised an eyebrow.
"Princess Celestia, please, you have to kill it!" Shining Armour called out hoarsely. "Burn it to cinders!"
"Brother!" Twilight said, trying to calm the terrified stallion down.
Celestia shook her head, the serene ruler of Equestria returned once more in full. "I don't kill, my Captain, and certainly not one who has surrendered. The changeling will pay for her crimes. Please do not be afraid of that."
"Not the changeling!" he yelled desperately. "That damned thing next to her!" He pointed an unsteady hoof accusingly at Cadance.
"Oh Cadance," Celestia said slowly, "what have you done?"