Thanks to Claudia Donovan for the help in making a picture for this, expect more for each chapter as time goes on.
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Rainbow Dash's wings beat against the wind, her mane whipping about her gracefully. She straightened her back, slicing through the air. Her eyes watered, the rushing air stinging the delicate orbs. She shut her eyes for only a moment, but was just long enough for her to lose her focus. She flapped her wings faster, attempting to slow her descent. She spiraled towards the earth, bracing herself for impact. She crashed through a large window, the sound of shattering glass filling the air. She crashed into the ground, her body flailing around as she tried to regain balance. Her back slammed into a wall, knocking all of the air out of her lungs. She coughed, groaning with pain. She looked up, spotting a very angry looking Celestia.
"Oops." Dash laughed a bit. "Sorry about that, princess, guess I landed a little too roughly."
Celestia glared down at her. "How nice of you to drop in." She hissed.
Dash blinked, taken aback by the princess's break from her usual kindness. "Um... Is something wrong, princess?"
"Yes, but it's fine now." Celestia shook her head, trying her best to put on a smile. "In fact, I was just about to go get you."
"Me? But why? Unless..." Rainbow Dash gasped, her mane standing on end. "The Wonderbolts wanted to see me, didn't they?! I'll bet they want me to try out, don't they?! I showed up just in time!"
"Silence!" Celestia barked.
Dash cowered a bit, taken completely by surprise. "You sound like you need a break, princess."
"Guards." Celestia called. "Take this one to chamber Delta Zero."
"B-but princess, isn't that where we're keeping the-" The smaller of the two guards asked.
"Silence!" Celestia stared at the guard. "Or would you rather go in her place?"
"No ma'm." The guard shook with fright.
"Good one, princess. Pretending you're going to throw me into a dungeon. Classic." Rainbow Dash laughed.
Celestia looked coldly down at her. "Take her out of my sight."
Rainbow Dash blinked. "What?" The guards grabbed her arms, dragging her out of the room as Celestia turned from Dash. Rainbow dug her hooves into the ground. "Okay, this isn't funny anymore." She quickly looked from guard to guard. "Hey, I said stop!" She started to flail around wildly. "Let me go, you jerks!" She kicked wildly, unable to wriggle from the guards' strong grip. She sighed, looking around her. They were in a part of the castle she had never seen before. The walls were made of greying stone, rather than the white marble that made up the rest of it. Moss poked through a few cracks in the stone, making it all the more dismal. There wasn't a window in sight, the hall lit only by a few dim torches affixed to the wall. Rainbow Dash struggled and kicked, her hooves making loud clicks on the stony floor. "Who the hell do you two think you are?!" Dash screamed at them.
The guards did not answer her, but just continued their walk. They threw her into a small cell, stone being the only thing this room was made of. There was no bed, no anything. The only sign of difference in the room was a rather large hole in the wall, a large pile of dirt leading up to it. A small torch flickered on the wall just above the hole, giving little light to this dark abyss.
The larger of the two guards turned to the other. "Think he'll come back?"
"He always does. It is just around dinner time, after all." The other guard smirked a bit. "Have fun, little pony." He shut the iron door leading into the cell.
Rainbow Dash sat in the corner, her mouth wide open in disbelief. "The princess is... bad?" She shook her head. "No. There has to be a reason for this." She thought of something that she may have done that would have caused the princess to become angry. A low rumbling echoed throughout the chamber, growing gradually louder. Rainbow looked around, trying to find the source of the sound. Dirt flew through the hole, a familiar snarling passing through Rainbow Dash's ears. She gasped. "Diamond dogs!"
A large beast burst through the wall, growling angrily. "They took my gems! They took the gems! I want them! I need them!" The beast sniffed the air, turning to the corner in which Rainbow Dash had been thrown. "Well, well, well. If it isn't a pony."
"Stay away from me, Diamond Dog!" Rainbow Dash stood, her legs a bit shaky from being dragged all the way here.
"You... you are friends with the whining one!" The Diamond dog gasped. He was brown, his red vest tattered and covered with dirt. His jagged mouth was pulled into a pained expression. "Please tell me the whining one is not here!"
"Rarity?" Rainbow Dash asked. She thought for a moment. "Yeah, she'll be down soon." She said. "You'd better leave. In fact, take me with you."
The Diamond Dog cocked his head in confusion. "Wait just a moment... why would you want to leave as well? Unless she isn't coming."
"You're smarter than you look, Fido." Rainbow Dash smirked.
"No, no, no." The Diamond Dog shook his head. "Fido is my subordinate. I am Rover."
"Oh..." Rainbow Dash blinked, thinking she had been making a joke. "So, what are you in for?"
"I came to your precious princess with a request that she found... unsavory." Rover waved a large paw.
"What was it?" Rainbow Dash narrowed her eyes, unsure of what his request could be.
"I asked for a truce." Rover sighed a bit. "For thousands of years the ponies and Diamond Dogs have been fighting, and I want it to end."
"What? You are the ones that aren't content with what you have!" Rainbow Dash said angrily.
"Should we be happy to live out our meager lives underground, unable to see the sun, unable to do anything but look for gems? We don't even have anything to do with them! We only do it because there is nothing else to do!" Rover threw his paws in the air angrily, his knuckles bumping the low ceiling.
"Why do you have to stay underground, anyways?" Rainbow Dash asked, unable to understand why she was listening to anything this thing had to say.
"A thousand years ago, the Diamond Dogs were the princess's royal gem collectors, and in fact, the Diamond Dogs were once ponies." Rover explained.
"That can't be true!" Rainbow Dash's jaw hung in disbelief.
"But it was!" Rover insisted. "All of the gems that were on the princesses' gowns, their crowns, their jewelry, all of it was found by us. We had been nobly performing the job for decades when the shift happened."
"The shift?" Rainbow Dash raised an eyebrow.
"The shift in power. Princess Luna took over the castle, and stayed there for months before Celestia banished her." Rover looked sadly to the ground. "The Diamond Dogs stayed loyal to the throne, rather than siding with Celestia."
"This is crazy." Rainbow Dash shook her head.
"By the time that Celestia finally came back to power, Luna had changed us to be more suited to the job of digging for gems. We were turned into this." Rover waved a hand at himself. "Once Celestia came back into power, we served as reminders of her sister's short rule, so she banished us underground. Honestly, we kidnapped your whiny friend because we were jealous. She was everything we should have been, what we used to be. And she was the descendant of the one Diamond Dog that had managed to escape, she was the descendant of the one Diamond Dog that watched as his friends were turned into... into this..." Rover sat on the floor, his head in his hands. "We've terrorized ponies for years because that is our way of getting revenge, our way of feeling like maybe if we can just make life bad enough for ponies... maybe the ponies would know how we felt."
Rainbow Dash stayed silent. She thought for a long time. "If what you're telling me is true..."
"It is." Rover interrupted.
"If what you're telling me is true..." Rainbow Dash continued. "Then maybe I can help you. I kind of have an in with the princess."
"Then how did you end up here?" Rover asked a bit irritably.
"Good point." Rainbow sighed. "How long have you been here, anyways?"
"Weeks, months, who knows? Time means nothing to me, I haven't even seen the sun since the day we took your whiny friend." Rover sighed.
Rainbow put a hoof on the Diamond Dog's shoulder. "I believe you." She said. "I don't know why, but you don't seem so bad anymore. So you used to be a pony?"
"I still am inside. I still feel like my horn should show up any day now." He sighed. "I tried digging out, but something deep inside myself told me to stay." Rover thought. "Maybe we were fated to meet."
Rainbow Dash laughed. "Cool your jets, loverboy."
Rover blushed a bit. "I'm not even a pony, how could I even think about that?"
"Like you said, you're still a pony inside." Rainbow Dash shrugged. "I suppose it's natural. But right now, we have bigger matters to attend to."
"Like?" Rover asked.
"Like how to get you back to your old self." Rainbow Dash said. "I think I'd like to see the master unicorn that was reduced to a sniveling puppy. I hope he's cute."
Rover laughed a bit, his raspy voice echoing throughout the small room. "Well, I hope this is your old self, because it is pretty cute itself."
Rainbow Dash felt her cheeks redden a bit. "Wow, that's the first time I've ever heard that."
Rover chuckled. "That's surprising."
"Anyways, if you're done hitting on me, I'd like to get out of here." Rainbow quickly changed the subject.
"Well, I had more, but as for right now, you're right. This hole goes directly next to some of the other chambers. What do you say about a good, old-fashioned riot?" Rover smiled maliciously.
"Sounds perfect." Rainbow Dash smiled. "And after that..." She clicked her hooves together evilly. "What say we pay a visit to the princess? I believe she has quite a bit of explaining to do."
"I believe she does." Rover laughed. "Alright, I'm going to finish my tunnel, they'll expect me to, anyways, but I'm not sure they expect me to gather up other prisoners."
"I sure hope not." Rainbow Dash sighed a bit.
"Oh, don't worry, I'm sure that we'll get out fine." Rover smiled at her.
Rainbow Dash looked at him. Strangely, his gravelly voice offered her reassurance, and a feeling she'd never felt before. She kissed him gently on the cheek. "Good luck."
"With that..." Rover smiled. "I don't think I'll need it." He hopped into the hole, humming as dirt was flung into the cell.
Rainbow Dash put a hoof over her mouth to block the dirt from getting in. She smiled a bit. She didn't know what this strange new emotion was, but she liked it. "A lot." She whispered quietly to herself, feeling her heart flutter a bit.
The End of Rainbow Dash's Story