A Canterlot Engagement Party

by Princess Lona

First published

Months before the events of A Canterlot Wedding, Queen Chrysalis was already putting her plans into action. First Sergeant Flash Sentry has been assigned Royal Bodyguard duty. Can Flash and Cadence stop the Changeling invasion before it begins?

Flash Sentry's first Royal Bodyguard Duty assignment for the Canterlot Royal Guard was supposed to be an uneventful evening, but when Princess Cadence is kidnapped and carried off by a mysterious look-alike on the night of her engagement party, Flash trails them into the Canterlot Caverns and learns that all of Equestria is in danger! What can a single pegasus who can't even get over his nervousness around royalty possibly do to stop an invasion? This is a Flash Sentry backstory fic, intended to stay as true to canon as possible.

A Canterlot Engagement Party

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Flash Sentry polished his helmet against his wing for the thirteenth time. He put it on, repositioned it, took it off, and then put it on again. He looked into the mirror that hung above the dresser in his tiny Canterlot apartment and gave a serious stare. He smiled. "Good night, Princess" he said. He redawned the serious face. "Good night, Your Highness," he barked. Barked? No, that wouldn't be right either. He had to hit just the right balance of professional and friendly. Flash sighed and tried again. Talking to soldiers was easy. There were clear rules about when to speak and to whom to speak, and the general idea was to communicate necessary information with as much concision as possible. There were no pleasantries within the Canterlot Royal Guard, that was the main reason Flash had made First Sergeant in the first place. There were no social cues to mess up in the guard, but with royalty the rules were different and vague, and sometimes they were even nonexistent! If he was going to make it through this night without embarrassing himself, he would just have to hope there would be no opportunities for talking.

Flash was about to take the next step in his military career– Royal Body Guard duty. His own captain, Shining Armour had just gotten engaged and Flash was to play an important role in the engagement celebration. He might have had a moment to feel happy for his captain, if Armour had decided to get hitched to anypony other than a princess. Canterlot royal engagement parties were renowned for their extravagance and grandiose celebration. Traditionally, the parties would take place at the castle lasting three days and nights, during which time the guests stayed at the castle and the bride and groom were not allowed to be alone together. It was an obsolete tradition, dating back to the age of chaperoning (just another bland and useless fact Flash seemed to be able to remember with ease despite not, apparently, having the mental capacity to exchange monosyllabic greetings). Captain Shining Armour and his fiancée, Princess Mi Amoré Cadenza would attend three days of dinners, informal teas, balls, and other celebratory functions. They would leave these events separately and retire to different bed chambers which would, according to custom, be guarded overnight. Flash had been waiting for his next chance to advance his rank so when Captain Armour asked him personally to be the chamber guard for Cadenza, the opportunity was more intoxicating than the honour. He could remember the captain's words: "You're the most stringent observer of rules in the entire guard, Sentry. I think you're just the pony for the job." It was only later that Flash realized he would have to interact, if only for a little bit, with the princess herself.

The captain had been making a joke at Flash's expense. He was known throughout his battalion as a stickler for rules. Nopony really minded this about him. Except Flash himself. He liked rules because they gave him a sense of peace in his moment-to-moment life. When there was a set of rules to follow, a predetermined arrangement of how events were to unfold, then he didn't need to worry about how he was handling the situation. Flash followed the rules because rules are so wonderfully uniform, uniform enough to hide behind. But deep down, He felt boring. He was afraid that if he tried to make his own rules, he would fail and other ponies would realize that he didn't actually have much of a personality of which to speak.

Well tonight that was going to change. Tonight, the first night of the engagement party, Flash would exchange pleasantries with royalty. It would be friendly, casual, and just the sort of thing a confident pony of average charisma would say. It wouldn't be "yes Sir", "no Miss", "at ease", or "attention". It would be a small thing, but it would set him on a new course. And it would happen right away. The castle clock struck midnight, the inaugural feast would be ending soon and the guests leaving. Flash gave his helmet a final adjustment, then ran out into the street and towards the castle quarters.

Rich, golden light streamed from every window of Canterlot Castle and Flash noted the silhouetted profiles of party guests behind the panes. Bypassing the main doorway, he took a cobblestone sidewalk around to a side entrance and headed for the princess's bedchamber. He had already marked the location of the room and spent some time familiarizing himself with that section of the vast building. Two pegasus guards stood on either side of an archway leading into the ballroom. They saluted as Flash passed by. He absentmindedly half-saluted back, thinking about how much easier it would be if all discourse could be so formal. He found the door that was to be his post for the night and waited for the arrival of his charge. It wasn't long before he heard the cold clip of hoofsteps on the marble floor and the captain and the princess appeared at the end of the hall, followed at a middling distance by a unicorn guard. Their voices and laughter got closer as they talked about the events of the ball they had just left. In stoic, Royal Guard fashion, Flash looked straight ahead and stood tall and still, pretending he was able to not pay attention to what they were saying. The sweat beading inside his helmet began to chafe his forehead ever so slightly.

"Well this is where I leave you m'lady." said Shining Armour as they stopped by the door. Flash heaved an inward sigh. They had not acknowledged him. Shining turned to the unicorn guard. "Thank you, Private Sabrewind." He said with a laugh. "You've done your duty well tonight but your services are no longer required. Dismissed".

"Yes Sir" said Sabrewind, saluting. Then bowing to the princess, he took his leave.

"And who will be the pony to take Private Sabrewind's place and keep me safe tonight?" asked Cadenza with mock concern.

"My darling," said Shining, "allow me to introduce your bodyguard for the evening; First Sergeant Flash Sentry." Flash bowed.

"Your Highness," he said. So far so good. This was a formality in which Flash was well-trained.

"Pleased to meet you, Sergeant," said Cadenza. "It's good to know that my fiancé has put one of his best soldiers on guard to keep him away from me tonight." The couple chuckled. Flash felt uncomfortable. He knew they were not laughing at him, but at the absurdity of the archaic tradition. Still, he was representing that tradition at the moment and was not sure what to say in response or if it would be too informal to join in their laughter, so he tried to smile casually. The effect was jarring when paired with the sentinel stance which he had retaken immediately after he bowed. Two silent seconds followed. With perfect poise and charm, the princess smoothed over the awkward moment, addressing Shining Armour:

"Goodnight, honey. Don't be late for Princess Luna's Official Royal Engagement Party Pre-Breakfast Paintball Match tomorrow."

"I won't miss it." said Shining Armour. He kissed her cheek and headed down the hall.

"Goodnight, bodyguard." said Cadenza.

"Goodnight Princess." Flash stammered, but she was already inside and closing the door. He was all alone in the hallway. That could have been worse, he thought. He had made it through "goodnight". All he had to do now was wait a few hours and make it through "good morning".

Time passed slowly and Flash occupied his mind with observing the details on the moulding across the hall. The palace grew quieter as the remaining guests left the ball and retired to their own rooms. Then the castle staff came in to clean up the remnants of the party and set the ballroom for the next function. Flash heard the scrape of chairs being moved across the polished floor, the billowing of crisp, pressed tablecloths unfurling, and the muffled clink of silverware being set down on the new linen. Eventually those sounds died out too, along with the gossip of the staff as they left for their own homes. The castle was dead quiet. It was probably now only a few hours before dawn. The princess had not yet stirred, nor had her door opened once. This is why Flash found it more than a little strange and amazing when he heard hoofsteps to his right and turned his head just in time to see Princess Mi Amoré Cadenza herself turning the corner at the end of the hall.

His amazement ceased immediately though, when he remembered that as an alicorn princess, Cadenza could easily slip by any pegasus guard unseen. She's probably going to sneak a visit to Captain Armour, he thought. This put Flash in a delicate position. He certainly did not think it his place to tell two grown ponies how to conduct themselves at their own engagement festivities no matter what some crusty old tradition dictated, but neither did he want to shirk his duties and disregard the rules on his first bodyguard assignment. What if the captain had asked the princess to do this as a test of Flash's guardsmanship? Then again, what if they set it up as a test of his discretion? Flash decided he would follow Sabrewind's example and trail the princess quietly at a safe distance. Rushing as silently as he could to the end of the hall, he turned the corner just in time to see her turn at the end of the next corridor. He followed her again but when he rounded the next corner she was nowhere in sight and there were two ways she could have gone. Flash listened. He thought he heard hoofsteps to the left. He followed the sound but the palace halls were large and empty, and after turning a few more corners he knew he had lost her. It was actually something of a relief. He had done his duty to the best of his abilities without having to deal with an awkward confrontation, and he wasn't exactly sure what following princess Cadenza was going to accomplish anyway. There was nothing left for Flash to do but return to his post.

The pale blue light of night lit the halls dimly as Flash retreated easily through the area he had committed to memory. Back in the corridor which contained Cadence's room, a thin sliver of bright firelight cut across the floor. The chamber door was open a crack. It had been fully closed when Flash had gone. He approached with quiet caution so as not to disturb the princess or any visitors she may have been entertaining. He had no intention of peeking in, he only wished to retake his proper guard position, but as he got closer he could hear raised voices and a loud crash. Quickly, Flash put his eye to the crack in the door.

He could hardly believe what he was seeing. Two Princess Mi Amoré Cadenzas! They stood horn to horn on the bed, locked in a fierce stare down. Two completely identical alicorns, both with the same pink coat, the same three-tone mane of yellow, mauve, and purple, same eyes, same horn, same cutie mark. On the floor next to the nightstand lay a shattered vase. Flash crouched but continued to watch through the crack in the door. One of the Cadenzas spoke:

"That single bodyguard of yours was too easy to get rid of. And here I hoped I was usurping an important princess. Maybe I should have just gone straight for Celestia after all."

"You'll never get that far," the second Princess Cadenza declared fiercely as she unleashed a wave of magic that knocked the other back a step. The first Cadenza gritted her teeth and lowered her head.

"You'll not be trying that again!" she seethed as a sinister green splurt of viscous goo leapt from her horn, landing on the other's horn. It crystallized immediately into a hard, transparent green casing. The princess (for Flash now inferred that the one flinging goo around must be an imposter) strained to break the seal over her horn, but in vain. Her magic was impeded. The imposter Cadenza laughed.

"My enchanted biocrystal is immune to your love magic." she chuckled and aimed another splurt of goo to land on the princess' wings, sticking them to her sides.

"Who are you?" Princess Cadenza demanded as she turned to aim a kick at the other's head. The imposter dodged.

"A princess never reveals her secrets," she said smugly, "at least not here." Using her green-hued magic, she picked up her prisoner as a small point on the floor turned black. The black speck grew and a gaping hole opened before Flash's unblinking eye. The imposter stepped down into it, taking the captive princess with her. They disappeared into the darkness and the hole began to close. Flash thought about what to do as the opening got smaller. He could sound the alarm, but what good would that do? By the time backup arrived, the hole would be closed and since it was obviously magic, he wasn't sure if anypony had the means to reopen it or even where it led. For all he knew it could be a portal to another dimension. The hole in the floor was now barely large enough to fit a pony, there was no time left. He flung the door open, dashed into the room, and jumped into the hole just as it finished closing, leaving an empty chamber without a trace of its occupant.

Flash tumbled halfway down a flight of stone stairs and landed hard on his chin. Looking up he could see the two Cadenzas ahead of him, the faint glow of the impostor's horn casting flickering shadows in the darkness. Flash ducked into a crevice until he was sure he had not been seen. What should he do? What could he do? Royal Bodyguard duty was really only ceremonial, it was common knowledge that alicorns are far stronger than any other pony race. Having a pegasus bodyguard for a princess was like asking a breezy to guard a dragon. Perhaps if a normal pony had tried to harm the princess, Flash might have been helpful in saving her from having to get her hooves dirty, but this was another alicorn just carrying the princess away, and, as he now noticed, changing? Flash knew he could be of no direct help to Princess Cadenza, but it was too late to turn back now, and he had to at least try to figure out what was happening.

Gingerly, he stepped out from his hiding place and crept along in the shadow of the wall. The princesses were quite far ahead now and he caught up as quickly as he could while maintaining silence and followed as close as he dared. Nearer now, he confirmed what he thought he saw; the imposter princess was changing. The tip of her horn had turned black and the colour was slowly creeping down and beginning to cover her forehead. As she changed, she spoke.

"I hope you don't take it too personally, Your Highness," (she drew the words out with great disdain and sarcasm) "but you really can't blame me for doing this. I could smell the love drifting around your saccharine city from miles away. It seems to seep out of the very cobblestones ever since you got engaged to that captain fiancé of yours." The change had now spread over her face, revealing two green eyes with narrow pupils and a sickly sea foam mane that was ratty and full of holes. "I've had my eye on Equestria for some time now, but I wasn't sure where to stake the initial claim. Now I have found the perfect stallion to provide for my subjects. In Canterlot we shall feast!"

"Don't you lay a hoof on Shining Armour!" screamed the unchanged Princess Cadenza as she struggled, suspended in the air.

"Oh I won't," said the other, "not at first." Her pink feathered wings disappeared and a set of tattered, gossamer wings appeared on her back. She grew taller now as well. "I'll need him to act as doorman to my dinner guests. Your dear Princess Celestia won't be keeping me out this time."

"So it was you who attacked the Castle last week," said Cadenza. "How did you get past Shining's protection spell and back in?"

"Isn't it obvious?" said the other, "The element of disguise." Her legs took on the black of the rest of her coat and a few small rounded chunks of flesh disappeared from her body here and there. Flash, who at that moment was hovering near the ceiling, began to realize what he was looking at. As the tip of the curly purple and yellow tail finished transforming to limp, drooping green, he remembered reading about these creatures. This was a changeling! A four-spired crown appeared on the creature's head. Flash gulped. This was a changeling queen!

The previous week's attack had been peculiar and Flash now understood why. A group of castle guards had been ambushed by a blue and white unicorn. They managed to get him to retreat, but when they chased him around a corner he was gone. There was nopony there but the gardener who claimed to have seen nothing. Later on, a purple pegasus flew into the throne room and made a dive toward the thrones, but darted out the window when she realized that both princesses were out. Stranger still, the gardener was found that night tied up and gagged in a shed, but said she hadn't seen any blue and white unicorn or purple pegasus, and that she had been captive since early morning. It didn't add up at the time. Now it was clear to Flash what was going on and just how great a threat it was. Changeling hives held hundreds of thousands of drones. Shining Armour had cast his protection spell around the whole city after the strange attacks and nopony was allowed in or out without going through Canterlot customs. It was an easy enough spell for the seasoned captain, but it would be no use if the Royal Guard was not made aware of the deceitful creatures that were plotting to attack again.

The changeling queen ducked and passed through a low archway into a smaller tunnel. Flash felt his knees almost buckle beneath him as he landed to follow. His heart beat faster and he had to actively keep himself from breathing too loudly. The trio pressed on. Deeper and deeper the queen carried the princess down into the depths below Canterlot with Flash sticking to the shadows in pursuit. With nothing left for Cadenza or the queen to say, they carried on in silence with only an occasional excited, hungry titter of laughter from the changeling or a grunt from Cadenza straining against her bonds.

Flash tried to think of a plan and looked around for some means to free the princess. If only she could access her alicorn magic for just a moment it could be enough to catch the changeling off guard. But it was too dark in the caverns to spot any means to aid in freeing her, with only the glint of changeling magic reflecting off of the polished crystalline cavern walls to light the blackness. He also wondered just what this changeling had planned.

Eventually they emerged from the tunnel into a wide open cavern. The ceiling was too far up to see and the far wall was invisible in the dark. The floor suddenly dropped off after about a hundred strides into a sheer cliff with no visible bottom. To Flash, it felt like standing on a floating platform suspended in a dark void.

"This is where we part, Princess." said the queen with a laugh and strode closer to the edge. "Once I'm rid of you there will be no one to stop me from gorging on the love that handsome fiancé of yours feels for you. And the citizens of Equestria won't be far behind." Flash's ears drooped and his jaw dropped. She was going to throw the princess, incapacitated wings and all, over the cliff! The queen stepped right up to the edge. Cadenza struggled furiously against the magic grip. As the queen held her suspended above the drop, Cadenza looked down into the abyss.

"Shining Armour," she whispered, closing her eyes. Then she opened them and flung a look of defiance at the queen. "You may do this to me," she spat, "but you will never carry out your plans. Shining Armour won't be fooled. Equestria will not be yours."

"I doubt that," said the queen and released her hold on her prisoner. Flash didn't think this time. He didn't have time. With a speed he didn't even know he possessed he shot out from hiding, his feet just grazing the ground as his wings propelled him past the surprised queen, over the ledge, and down toward the falling princess. He managed to grab her back legs. The weight of an alicorn combined with the hard, green, changeling biocrystal that still gripped her wings and horn was almost too much for him. He strained against it, his wings pumping, and managed to land them both back on the edge of the cliff. Flash fell into a panting heap while Cadenza lowered her head and snorted steam at the approaching queen, now recovered from her start.

"Save your puffing, Princess," the changeling's ghastly tone echoed through the vast cavern. She turned to Flash with mock admiration. "My my, the bodyguard. It would seem you're better at your job than I had previously deduced. Congratulations. Allow me to reward your efforts." She lunged, horn first at Flash who was at that moment, too exhausted to move. He watched her charging towards him. She seemed to be moving in slow motion but somehow he wasn't able to get out of the way. She was almost upon him now, and he reflected on the duty he had done to the best of his abilities, and how even if his Royal charge never made it out of this, at least he had kept her safe for a few moments longer.

A pink blur cut off the sight of the queen and a loud clash reverberated throughout the chamber. Princess Cadenza stood between Flash and his aggressor.

"You will not harm this soldier!" her voice was clear and commanding and it moved Flash back to his senses. He scrambled to his hooves and emerged to stand next to her, dawning the most serious of the faces he had tried on earlier in his apartment. The queen, who had been locked on Cadenza with both horn and eyes now took a step back and paused. Then she started to laugh.

"A ha ha ha! The two of you look ridiculous! Standing there facing me with a gorge at your backs, your power unusable. It's absurd! I believe I will reward you after all, bodyguard. Instead of disposing of your precious princess as I had originally planned, I think I'll leave the two of you down here together to keep each other company while you starve. Maybe some of that loyal citizen love of yours will waft up to the surface for me to snack on while I prepare the main course." As she spoke, a dark, green-rimmed mouth like the one by which they entered the cave opened behind her and she backed toward it.

"Good luck finding your way out," she whispered as it closed around her. Flash and Cadenza both ran towards it as it cut them off from the queen, but it closed just as they reached it and left them with only the fast-fading ring of her laughter. They were now in nearly complete darkness. Cadenza's horn was still inhibited by the changeling magic and with the queen gone the only illumination available was the faint glint of the crystal walls reflecting light from far away near the surface. They stood there in the dark silence taking in their situation and finding themselves relieved at least to be free of the queen.

"It's Flash Sentry, right?" came the now collected voice of the princess.

"Yes Princess Mi Amoré Cadenza." Flash croaked into the darkness

"Cadence is fine," she replied.

"Yes, Princess Cadence." He was happy she could not see him shifting his weight from side to side as he used her less formal name.

"Thank you, Sentry," Cadence continued. "Without your vigilance I would surely have perished." Flash felt the urge to point out that she had already repaid the favour by stopping the queen from charging him, but he didn't want to use the word "favour" to describe the carrying out of his duty, and he couldn't think of a good way to phrase it, and it had now been about three seconds since anypony had said anything, and the silence was agonizing.

"No thanks necessary, Your Majesty."

"We've got to get out of here," said Cadence. "Shining Armour is in danger and he won't have seen this coming. I hope at least Celestia will see through her." A hundred million thoughts flowed through Flash's mind: The captain is very perceptive, he'll notice. Princess Celestia must have crossed paths with changelings in her long life, surely she'll detect the ruse right away. The changeling does not know enough about Your Highness to pull off a proper impersonation, somepony is bound to figure out it's not you. But he wasn't sure if it was his place to comfort a princess, so he kept quiet.

"If only we had some more light," she went on. Flash's eyes immediately gravitated toward the only source of light - the faint sheen of a crystal near the archway by which they had entered the room. Automatically, his eye slid along the trajectory of the angle of the clean-cut crystal and noticed, very faint above the opening, another crystal reflecting the same beam of light onto the first crystal he had seen. The faint light beam appeared to have come from somewhere else but he wasn't standing at the correct angle to see. It had to be coming from somewhere though...

"There's another way out of here!" he exclaimed. Cadence jumped at the raised voice coming out of this otherwise placid pegasus.

"What do you see?" she asked, moving closer to the sound of his hoofsteps. He was now moving to get a better look at the nearly imperceptible light. There. He could see it. Previously cut off from his sight by a dark platform of rock, Flash now saw the beam of light which was reflecting down a second long tunnel, bouncing off of different shiny stones along its way. Closer to the source of the light, Flash could see that it had a green hue. The same green light cast by the changeling queen's horn.

"There!" he whisper-shouted so as not to be heard, "She's that way, come on!" He hopped up excitedly onto the platform before remembering himself and adding "Your Highness." Cadence looked down the tunnel at the beam of light.

"Good work, soldier" she said as he offered her a hoof up onto the platform.

They proceeded down the corridor, passing the reflective stones that transported their beacon. With each one they passed, the light grew brighter and greener. They were gaining on the source.

"How did this happen?" pondered Cadence aloud. Flash flushed in the dark.

"It was my fault, Your Highness." he admitted. "She tricked me and lead me away from my post." His head hung slightly.

"No," continued Cadence, "I mean, how did you find us? She closes the holes she opens up behind her." Flash's head drooped even lower. He confessed:

"I came back to your chamber after she had already broken in and watched through the door, then followed you into the caves before she closed the opening. I couldn't challenge her. I was cowardly." Cadence stopped him in his tracks and bent her head to look him in the eye. She had to come very close in the dim light.

"Why didn't you reveal yourself in that moment?" she asked. Flash was flabbergasted. Could she really not figure it out?

"What could I do in battle against an alicorn?" He didn't really ask the question. It was more of a statement.

"Exactly," said Cadence. "You kept a clear head and played your advantage by remaining hidden. You've been a much greater help to me down here than you would be laying unconscious or worse on my bedroom floor. A coward wouldn't have even followed." Flash brightened. He smiled sheepishly and adjusted his drooping helm.

"Now let's go stop her." said Cadence and started with renewed conviction in the direction of the light.

"Wait!" said Flash. Immediately after crying out, Flash felt he had put too much command into his voice. He wanted to stop and apologize for the outburst, but the idea in his mind pushed him to keep talking. "We know we're no match for her in this state, so challenging her would be no use." Cadence did not like to admit this, but it was true. Flash went on, thinking as he spoke. "She thinks we're still down there, and we know she's heading back to the surface. If we can sneak back out with her, we can get help, and warn Captain Armour and Princess Celestia." Cadence nodded and they continued cautiously.

The tunnel they had been following climbed steadily and now they found themselves looking out of its upward-facing mouth into another large open room, this one with a domed ceiling and no floor at all. The light was shining down from near the top. Flash squinted into the darkness. The changeling queen was there, flying on her bug wings along the wall. He looked down. Far below, almost completely obscured by the blackness, was the platform where the queen had tried to drop Cadence and below it, the bottomless, empty pit. They climbed up out of the tunnel and found only small outcroppings near the wall to cling to, and the long drop below.

"Hurry after her," whispered Cadence, "I still can't fly."

"But I'm supposed to be guarding–" Flash began.

"I'll be fine," said Cadence. "Our only hope is in you finding a way out of here. Go." Flash nodded and silently took wing. It was hard to keep in the shadows the closer he got to the queen, as her sickly light shone all around her. Looking ahead, he could not figure out where exactly she was going, but he deduced that her magic didn't create portals as he had previously thought, otherwise she would be back topside by now. No, her magic must only create openings in solid surfaces. She was probably heading for a place where she knew she would emerge unnoticed on the other side. If he could just follow her out.

Keeping in the air meant being in the open and visible if the queen turned around, so Flash landed on outcroppings whenever he could to hide behind the boulders that sat on many of them. The queen was circling the walls in an upward spiral. Flash noted that the outcroppings followed this spiral pattern almost like a staircase. Exactly like a staircase. This wasn't a random smattering of platforms, it was the ruin of an ancient staircase. So on the other side of the ceiling must be the outside, the palace! Or the city of Canterlot. They had traveled far and might not be under the palace anymore at all. He wished he could convey this information back to the princess, just in case something should happen to him. For now he pressed on.

The queen was near the top now. She flapped upward a few more times and landed on a platform jutting out near the pinnacle of the domed ceiling. Flash had been so focused on following her, he hadn't noticed the second light source peeping into the room. On the curved wall right next to the queen was a tiny crack and through it, the light of dawn slid into the chamber. It was such a small crack that the light wouldn't be visible very far into the cavern. The queen had led Flash to a potential solid exit. It would only take a few hours of chipping to broaden that crack to fit a pony. But of course, she didn't choose to use it herself. The queen once again began to open a magic, green rimmed hole. Now a stream of nearly blinding daylight flowed in and the queen, taking on the form of a young colt, stepped out into it. Again, there was little time. The safe thing to do was to wait for her to leave and then dig his way out, but Flash didn't know how much time he would have to spare once he and Cadence were alone again in the cave. A changeling that powerful could do a lot of damage in a very small amount of time, there was no telling how quickly she could power up feeding off of Shining Armour's love for his fiancée. He had to follow the queen out again. He wished he could at least have time to go back and tell the princess.

Just as he was about to fly up and through the hole, he had a thought, and he removed one of the silver plated horseshoes he wore as part of his Royal Guard uniform. He flew up and landed on the platform. As he passed the crack in the wall he dropped the shoe on its side with the sole angled toward the pit below. If Cadence had to get out on her own, the shoe would reflect the daylight down into the depths of the cave and help to guide her out. The hole cast by the queen was closing slowly. He had time to stop and adjust his trick so that it would reflect the most light. Judging from what he could see through the magic opening, this was an open section of the castle garden, sure to catch the noon sun. It was now dawn but if Flash set the shoe at a slightly more obtuse angle, it would catch the full sun at noon and reflect a strong beam deep into the caves. It would probably even reach the floor below. He was just about satisfied with his work when he felt a sudden pressure on his wings. He turned and saw the queen, changed back into her true form, standing over him, and looking right into his eyes as the hole closed up behind her. She had hit his wings with a coat of biocrystal which hardened instantly. He struggled but could not open them. The queen was no longer wearing the amused look she had shown below. Now she was furious as she addressed Flash in severe tones.

"I underestimated you again, bodyguard," she hissed. "That's one mistake I made twice. The mistake I won't be making twice is letting you live." She turned and kicked Flash from the platform. His flight reflex responded as soon as he felt himself falling through the air, but it only served to pull his muscles straining against the biocrystal. As he sailed past the princess he shouted "There's a light up there!" but his call echoed and bounced throughout the caves and he was sure she would not make anything of it. He just cleared the platform below and fell towards the pit into which the queen had attempted to drop Cadence earlier. Sensing the end, Flash gave up. His body went limp and he tried not to think about the ground that would be hitting him any second now. As he gained momentum, he instinctively curled himself into a ball, falling back first into the blackness.

Splash! The water was icier than the death he had imagined, but he welcomed it more than any feeling in the world. Of course! These caves were mines once, there would have to be a water source in them somewhere. It was a river, carrying him down a gentle slope. The cold water made most of his muscles seize and he struggled to the bank against the weight of his armour before he was completely immobile. Gasping and aching, Flash used the last of his strength to throw himself onto dry rock, then passed out in the dark.

He awoke sometime later. He wasn't sure how long, but it was long enough for his mane and exposed coat to dry. His tail trailed in the subterranean river. He was still wet under his armour as well and it caused him to shiver. He struggled to remove the armour and found that one of his front legs surged with pain and would not move correctly. It was broken where the changeling queen had kicked him. With great difficulty Flash removed his helmet, but his breast plate was covered in biocrystal where the queen had targeted his wings and trying to take it off only tore at his feathers. Even without removing the breastplate, he could feel a large bruise covering his entire back. The force of hitting even water at such a high velocity was more damaging than one might think. He shuddered as he thought of how lucky he was that he had not landed on his front. Above him on the other side of the river, the cliff face rose sheer and tall. The biocrystal was apparently waterproof as it held his wings as strongly as ever to his sides. He tried throwing himself against the rock wall to crack the crystal, but he found it only aggravated his injuries. Up was not an option. After a drink from the river, he limped off in search of another way out. Flash followed the river downstream. All this water has to flow somewhere, he thought. It was slow going, slower once his broken foreleg began to swell up. The river flowed in twists and turns, changing course with every slight change in the landscape. He hobbled along until he was tired and hungry, and curled up to sleep in a crevice. When he awoke, he did it again.

He travelled on and on like this with no sun or moon to tell him how many days had passed. Luckily, he discovered a thin yellow moss growing on the rocks near the water. It was acrid but edible, and it sustained him. The only light was the glinting of gems in the walls and the pale, dancing surface of the river. His leg only got worse from the jostling nature of his hobbling march and he began to fear he had made a mistake in following the river. He might be miles below Canterlot by now. In time the biocrystal began to weaken and flake off and after what Flash judged to be two weeks it was gone completely. He finally removed his breastplate, revealing painful welts where his wet skin rubbed against the rapidly tarnishing metal. Unfortunately, the armour had also cut deep into the underside of his left wing joint and the wound appeared to be infected. He tried to fly, but found that he could only hover for a few moments. He washed the wound in the river, but judged that it would be at least a month before the pain was diminished enough for him to fly. He continued his search for another escape. Despite the disappointment of not being able to fly once the bond on his wing had disintegrated, the mortality of the biocrystal gave him hope. If his had worn off, then the princess would be free by now too. This also worried him a bit. If she was free, why had she not come looking for him yet? He wondered what was happening on the surface.

Then one day or night it happened. The river disappeared. It flowed into a whirling pool and presumably drained downward from there. Flash was now guideless in the dark. He lay down by the pool and closed his eyes, trying to remember nice things to comfort him. The warmth of the sun, the sound of the sparrows on his window sill in the morning, the smell of apples. The smell of apples... Flash smelled apples. Real, distinct apples. He had been underground for so long now that he might not have noticed it if he hadn't also been trying to recall the scent, but it was definitely there. That sweet, bursting smell. He opened his eyes. There in the pool right under his nose, an apple core had gotten stuck on the rocky bank. Flash stood up. The pool was full of apple cores. And orange peels, and bits of paper, and tin cans. It was garbage! Real honest-to-goodness pony made garbage! And it was getting into the pool somehow. Flash had to investigate further, but first he carefully rinsed a few apple cores in the clean river and ate them. It was one of the basest things he had ever done and he hoped he wouldn't have to do it again, but gave him strength, both physically and in spirit.

Replenished, he walked around the edge of the pool. It was quite large and on the other side a small torrent flowed into it over the rock wall. This was where the garbage was coming from. If he could just get up to the top of the garbage waterfall he could follow the new river to its source. The torrent burst through the wall about 10 feet up. Flash jumped. He strained. He flapped and flopped and fell. It was no use. There was no flying up this measly ten feet. Hoof over hoof, he climbed the wall nearly straight up. It took most of his strength and when he reached the top he fell face forward into a sewer. A sewer! Flash would have leapt for joy if he wasn't so weak from hunger and exhausted from his climb. But now his senses returned to him. Wandering in the caves, he had nearly forgotten why it was important to get out. His captain, the city, and all of Equestria were in danger (if they had not already perished). The fresh trash floating past his hooves gave him hope that things were still okay up top, as he was fairly certain that changelings didn't eat apples. He mustered all of his speed and looked for an exit. Around the first corner he turned he saw a blinding white light and ran for it. As he got closer he saw a grating cutting the light. He doubled his speed and with all of his strength charged the grating. It was rusty and came off fairly easily.

Flash blinked in the daylight. It hurt his eyes but it also felt good, like drinking a strong cup of coffee. He stood on a cobblestone street near the edge of Canterlot. Ponies started at the sudden emergence of the dirty, emaciated pegasus from behind a sewer grate. Flash, who had almost forgotten how to speak, shouted as loud as his weak voice could muster:

"Princess Cadence is a fake! Summon the guard! Tell Princess Celestia, there's very little time!" A few unicorns looked at each other uneasily and seemed afraid to approach Flash.
"It's okay," he said, his voice failing, "I'm a sergeant of the Royal Guard." He began to feel dizzy. The fresh air surged through his bloodstream quickly. He had not expected the effect to be quite so intoxicating. He fell to his knees, coming down hard on his bad leg. He winced and fell over. "Please, you've got to stop her," he croaked hoarsely. He tilted his head back and looked up at the sky. The captain's protection spell was no longer there, these could be changelings all around him. A dark face moved into his line of vision it was private Sabrewind.

"Sarge?" he gasped quizzically.

"Sabrewind," said Flash with a cough, "she's a changeling. Warn the captain." The world went dark and he knew no more.

This time when Flash awoke he felt much more comfortable. There was something soft under his head and all around him the smell of clean linen. His broken bone had been set and cast and there was a tray of what appeared to be lunch on the table next to him. He was in a bed -not his own bed- and he could hear soft voices just outside the door. He groaned. The voices stopped and a moment later Shining Armour appeared in the doorway.

"Sentry!" cried Armour with a smile and a salute. "You're back!" The sight of the captain brought everything flooding back to Flash.

"Captain," said Flash trying feebly to salute with his broken hoof, "I know who made the threat against Canterlot. It was changelings. I don't know how many there are but I met the queen and-"

"Whoa, whoa, whoa, slow down there Sergeant," said Shining Armour. "It's not Captain anymore, it's Prince. And you don't have to salu-"

"He's awake?" Now it was Shining Armour's turn to be interrupted as Cadence entered the room. The next few hours were spent catching Flash up on the news of the past few months. He had been trapped in the caverns much longer than he realized. Maybe it was the exhaustion, or maybe it was the relief that everypony was safe, or maybe it was the painkillers, but Flash found it easier than ever to talk to the princess.

"But how did you find your way out of the caves?" He asked after everything was explained.

"When you fell I figured you were gone forever so I went looking for another way out," said Cadence. "I got a bit lost after days of searching. When my sister-in-law found me, we spotted a light back near the place where you fell and it led us to a crack in the wall. We broke through it and it found ourselves in the palace garden." Flash heaved a sigh and smiled.

Cadence and Shining Armour visited Flash every day that week. Evidently they were grateful for his help in the caverns, but he sensed there was something else. During this time he learned of the re-emergence of the Crystal Empire. He also learned that the princess and the new prince were now overseeing this new land, and that they would be returning there soon. On the night before their departure, Flash was discharged from the hospital and attended a farewell feast in honour of the visiting Royal couple. It still seemed a bit foreign to him addressing his former captain as Prince, but he knew he would get used to it. At the banquet he sat on Cadence's right, and it was not until she stood up to deliver a speech that Flash realized this banquet was being held at least partly in his own honour.

"This courageous pony risked life and limb in the name of duty," said Cadence, addressing the guests, "but his risks were not wanton, they were calculated and carried out with diligence and precision. He has shown himself to be mindful, calm, and loyal. These are all traits required in an inspirational leader, and without his efforts none of us would be here today." She turned to him now, still speaking in a voice meant for all to hear. "Flash Sentry, the Crystal Empire has only just returned from its thousand your slumber and there is much building to be done, including forming the Crystal Empire Royal Guard." Flash could see where she was going with this. His chest swelled as his face flushed. "Will you accept our invitation," (here Shining Armour rose to join her) "to come to the Crystal Empire, help us form the guard, and act as its captain?" Flash nearly choked on his cider. Captain? He was expecting the invitation to continue in Cadence's service in the Crystal Empire, but the invitation to be its captain was quite frankly, a move he felt the prince and princess had not considered fully. Fortunately he was in his element here. If Cadence had made him this offer while they were alone in his informal hospital room he would have coughed on his response even now after they had grown more familiar. But here at a formal banquet, with Cadence posing the question in the form of a flowery-worded speech, Flash could really sink his teeth into answering it. He rose.

"Your Majesties," he swept his voice down to accompany his low bow "Your words are kind but too large for a soldier of my stature. I gratefully accept the honour of serving in the Crystal Empire, but request that I keep my current rank of First Sergeant." Cadence was taken aback. Flash continued: "It is only out of a sense of duty that I cannot accept so leaping a promotion at this time. Perhaps one day, under the tutelage of our new prince I may rise to the challenge of leading," (Flash didn't really mean that, he knew what he was suited for) "but for now I feel I could better serve Your Majesties and the Empire as I am, without the added responsibility of leadership."

"Very well," said Cadence with a kind smile. Then turning to the dinner guests: "I present to you, First Sergeant Flash Sentry, the first official recruit of the Crystal Empire Royal guard!" The hall burst into applause. Cadence lowered her voice and spoke to Flash out of the corner of her mouth.

"Are your observations always this astute?" she asked.

"Sometimes," he replied.

"In that case, would you accept Head Intelligence Officer?" She smirked, but the question was serious. Flash grinned.

"Yes, Your Majesty."