Twilight Sparkle slammed open the doors to the library tower, far too worked up to feel winded after her gallop up the tall stairs. The young unicorn scholar's mind was racing and she knew with intuitive certainty that she was On To Something. There was no time to waste on trifles.

“Spike? Spiiike?” she shouted, but then looked down to see him flat on his back on the floor, having been knocked over by the doors as she entered. “Oh, there you are.”

Barely sparing him a second glance she galloped into library, running past Princess Rainbow Dash sleeping on her couch, and started to survey her vast collection of books. “Quickly, find me that old copy of...”

Twilight paused, frowning. Something about this situation seemed off to her. She mentally reviewed the scene that had just flashed her by, then turned around. “...Spike. What's that?”

Spike had picked himself off the floor and was busy removing a gift-wrapped box from his tail, having accidentally speared it when he was knocked over. “It was a gift for Moondancer...” he grumbled, pulling a ruined teddy bear out of the box. Stabbed clean through the heart. At least it hadn't suffered much.

“No, no. Not that.” Twilight pointed at the rainbow-maned, cyan-coated alicorn princess who lay curled up like a cat on Twilight's sofa, her small ruby-encrusted crown resting on the nightstand next to it. “That.”

“Oh.” Spike looked sheepish, scratching the back of his head. “Sorry, Twilight. She said it was okay that I let her stay for a while, and also that she'd have me thrown in the dungeons if I didn't.”

Twilight sighed deeply, marched over to the slumbering alicorn and cleared her throat. “Princess Rainbow Dash!” she bellowed in her best Celestia impression.

Rainbow Dash instantly sat up, looking around with bleary eyes. “Huh!? What!? It wasn't me!” She blinked a few times and finally recognized Twilight. “...Oh. Hiya.”

“Princess, what are you doing here?” Twilight asked.

“Napping,” Rainbow replied with a shrug. “Duh.”

“Yes, I can see that,” Twilight said. “I meant, what are you doing in this tower?”

Rainbow feigned a gasp. “Well now, that's just rude. Aren't I allowed to visit you once in a while, Sparkle?”

“Of course you are,” Twilight smiled gently despite her dry tone. “It's just that I never expected to see you in a library. Not voluntarily, anyway.”

Rainbow chuckled, idly levitating her crown to its proper place on top of her head. “Yeah, that's the brilliant part. They'll never find me here!” Her grin faded when her brain caught up to what she was saying. “Er, I mean...”

“Ah-ha!” Twilight pointed an accusing hoof at the princess. “You're skipping your magic lessons again, aren't you?”

Realizing she'd been outsmarted, Rainbow crossed her hooves over her chest and pouted. “That's non of your business.”

“It is my business if you decide to hide in my library,” Twilight said. “If Princess Celestia thinks I'm helping you play hooky, I'll get in trouble too.”

“Yeah, we can't have that, can we?” Rainbow rolled her eyes. “Heavens forbid the model student Twilight Sparkle ever does anything that might upset the mighty Celestia!”

Twilight frowned. “Princess Rainbow Dash...”

“And you can just call me Rainbow, okay?” the young alicorn added. “I know we're not exactly friends but we've known each other for years now. You don't have to use my title all the time.”

“Even so, you are a princess,” Twilight said. “Don't you think it's time you started acting like one?”

“Oh, don't you start that too!” Rainbow groaned. “I get enough lecturing from mom.”

“I just don't understand why you seem put so much effort into getting on her bad side,” Twilight said. “Skipping magic lessons, playing pranks on the guards, arranging improvised jousts, flying around the city doing air stunts in public. It's like you're trying to antagonize her on purpose.”

The princess turned her face away, and Twilight only caught a brief glimpse the deeply uncomfortable look in her eyes. “Whatever,” Rainbow sulked. “Let's just drop this subject, okay.”

“Fine.” Twilight rubbed her eyes with her hoof. It was a private family matter, after all, not something she should meddle in. More importantly, the whole debate had nearly made her lose her original train of thought. She paced over to one of the many shelves and grabbed several books with her magic. “Well, since you're here, you can help me look for my copy of Predictions & Prophesies.”

“Sure!” Rainbow immediately perked up. She turned to Spike. “Spike, find me... that thingy Twilight's talking about.”

Spike snapped to attention and made a quick salute. “Y-Yes, your Highness!”

Rainbow smiled as he scampered off. “He'll make a great minion some day,” she commented, ignoring Twilight's annoyed glare. “So, what's the big deal, anyway?”

“I'm not quite sure,” Twilight diverted some of her magic to levitate a large book out of her saddlebag, presenting it to Rainbow. “Here, look at this.”

Rainbow's horn lit up and her magenta aura replaced Twilight's purple one as she caught the old tome. She looked at it with a slightly puzzled expression. “It's a book.”

“Yes,” said Twilight with as much patience she could muster. “Now look inside it. Don't worry, there are pictures.”

“Hey! I do know how to read!” Frowning angrily, Rainbow opened the book and started skimming through the ancient legend written within. As Twilight and Spike continued their search through the library, the princess mumbled to herself as she read: “Uh huh... two regal sisters... harmony yadda-yadda... transformed her into a wicked mare of darkness. Huh, that's actually pretty cool... eternal night... most powerful magic known to ponydom... banished her permanently in the moon? Wow, that's harsh!”

As Rainbow reached the end of the tale, her eyes narrowed. “...The elder sister took on responsibility for both the sun and moon, and harmony has been maintained in Equestria for generations since.” She lowered the book and looked over at Twilight. “Wait, this story is about mom, right? I mean, that's her in the picture, isn't it?”

“It doesn't say that outright,” Twilight replied. She was still digging through her collection of old books. “But the context seems to suggest it's indeed Princess Celestia.”

“I had an evil aunt who tried to take over the world?” Rainbow scratched her mane. “And mom locked her in the moon forever? I didn't know about that.”

“Neither did I, or at least I didn't think so,” Twilight said. “But I'm positive I've heard about the Elements of Harmony before, and that why we need to find that...”

“Here it is!” Spike suddenly cried, holding up the book they'd been looking for. “Predictions & Prophesies, third edition.”

Twilight immediately levitated the book out of his claw. Rainbow smiled and patted him on the head. “Good boy.”

Spike scowled a bit. “I'm not a dog, you know.”

Twilight quickly flipped through the pages of the book. “Elements of Harmony... Elements... See: Mare in the Moon?”

“The Mare in the Moon?” Rainbow repeated, raising an eyebrow.

“Isn't that just an old pony's tale?” Spike asked.

“Mare... Mare...” Twilight kept going through the pages. “Ah! The Mare in the Moon, myth from olden pony times. A powerful pony who wanted to rule Equestria, defeated by the Elements of Harmony and imprisoned in the moon. Legend has it that on the longest day of the thousandth year, the stars will aid in her escape, and she will bring about nighttime eternal!“ She gasped. “Spike, Rainbow Dash, do you know what this means?”

The dragon and the alicorn shared a confused look.

“Not really,” Spike admitted.

“Yeah, I don't get any of this,” Rainbow said.

Putting the book aside, Twilight quickly levitated a quill and a piece of parchment to her assistant. “Spike, take a note please. To Princess Celestia.”

Spike nodded and started scribbling. “Okay...”

“My dearest teacher,” Twilight said and began to pace about the room as she dictated: “My continuing studies of pony magic have led me to discover that we are on the precipice of disaster!”

“Hold on,” Spike suddenly looked confused. “Preci... preci...”

“I think she means something really bad is going to happen,” Rainbow clarified is a sideways whisper.

“Oh!” Spike scribbled that down.

Twilight gritted her teeth, but continued her dictation. “For you see, the mythical Mare in the Moon is in fact Nightmare Moon, and she's about to return to Equestria, bringing with her eternal night! Something must be done to ensure that this terrible prophecy does not come true!”

Rainbow stared at her. “Wait, are you serious?”

“I await your quick response,” Twilight finished. “Your faithful student, Twilight Sparkle.”

“...Twilight ...Sparkle,” Spike repeated, putting down the final dot on the letter. “Done.”

“Great! Send it,” Twilight commanded.

“Now?” Spike asked.

Twilight turned to look at him, frowning. “Of course.”

“But don't you think Princess Celestia is a little bit busy right now?” Spike argued. “I mean, the Summer Sun Festival is, like, the day after tomorrow.”

“But that's just it!” Twilight insisted. “The day after tomorrow marks the thousandth year of the Summer Sun celebration. It's imperative that the princess is told right away!”

“Imp... Impera...?”

“Important!”

“Okay, okay!” Spike drew a deep breath and breathed out a bright green flame at the rolled up letter. The scroll immediately turned into a wisp of smoke that disappeared out one of the open windows. ”There, it's on it's way.”

Twilight nodded, looking pleased with herself. “Good, then all we have to do is wait for her reply.”

Rainbow walked up to her, giving the unicorn a slightly concerned look. “So, um, you do know this is crazy, right? This whole thing you're doing right now? Because it's totally crazy. Do you seriously think mom is going to believe any of this hokey old prophesy stuff?”

“Oh, I know she will,” Twilight replied. “Your mother trusts me completely. In all the years she's been my mentor, Princess Celestia has never once doubted me.”

Rainbow rolled her eyes. “Riiight.”

The next moment Spike's cheeks bulged and he burped out a green flame that materialized into another scroll.

“See?” Twilight said as spike unrolled the letter. “I knew she would take immediate action.”

“My dearest, most faithful student Twilight,” Spike read. “You know that I value your diligence and that I trust you completely.”

Twilight beamed a prideful smile at Rainbow. “Told you so.”

“...But you simply must stop reading those dusty old books!”

Twilight let out a sharp gasp and her widened in pure shock. “W-w-what?”

Next to her, Rainbow suddenly had a huge grin on her face. She nudged the unicorn in the side and giggled: “Heh, well what do you know? Seems like mom and I agree on something after all!”

“There is more to a young pony's life than studying,” Spike read. “Therefore I've decided to send you to supervise the preparations for the Summer Sun Celebration in this year's location: Ponyville.”

“But... I...” Twilight looked like she couldn't believe her ears. ”...What?!”

“And, I have an even more essential task for you to complete: Make some friends!“

“What!?”

Rainbow Dash was practically bursting with laughter. “Oh, wow!” she giggled. “Mom just ordered you to get a social life! This is priceless!"

“P.S,” Spike read. “Please tell my daughter that I wish to see her immediately.”

Rainbow choked on her laughter. “...Oh horseapples.”

The Grand Atrium was one of the oldest and most venerable parts of the royal palace. The long unbroken hallway led directly to Canterlot Tower, the impenetrable vault that housed the crown jewels and royal ceremonial regalia, various treasures of historical importance, and supposedly a collection of powerful artifacts from ancient times.  The atrium itself was two stories high with rows of windows on either side, filling the room with the sun's light at all times of the day. Every  second window depicted an important event from Equestria's history; the heroes, the miracles, the battles between good and evil, all immortalized in magnificent stained glass.

Due to an unfortunate history with broken windows, Princess Rainbow had rarely been allowed to roam the atrium as a foal. Not that she was very fond of the place anyway: There wasn't much to do except wander back and forth looking at the windows. On occasion, Celestia would have a new one installed to commemorate some historically important event. Even so, the number of windows always seemed to match the length of the hallway perfectly, yet it never appeared to be any longer than before. Rainbow tried not to think too hard about that. She understood that it was some kind of magic, but it still didn't seem right to her. The fact that she couldn't judge how large the room really was made it even more unnerving. Perhaps this was exactly the reason her mother had wanted to see her in this particular part of the palace? Rainbow certainly wouldn't have put that passed her.

She found Princess Celestia gazing idly at one of the windows – the same one, Rainbow realized, that commemorated her own birth. As she approached, Celestia aknowleged her presence with sideways look, she did not speak. That was never a good sign.

“You wanted to see me, mother?” Rainbow said, trying her best to sound casual.

"Yes, I did,” Celestia replied, her voice perfectly even. “And so did Professor Mandrake, as it turns out. You failed to show up to your magic lesson. Again.”

“Oh dear!”  Rainbow struggled to look surprised. “That was today?”

Celestia turned her head and gave Rainbow a bemused look. “Nice try.”

“Worth a shot.” Rainbow hung her head and sighed. “You're mad at me, huh?”

“No,” Celestia shook her head. “But I am disappointed.”

Rainbow shrugged slightly. “Yeah, well, what else is new?”

“Rainbow Dash!” Celestia finally raised her voice and her ancient eyes turned colder. “Do you think you can treat everything like a joke? You are practically an adult now, and this foalish behavior does not become you. As a princess of Equestria you have duties and...”

“Duties and responsibilities,” Rainbow cut in. “ I know, I know! You've told me like a thousand times already. But cut me some slack, okay? So I ditched a few of Mandrake's boring, confusing lectures. What does it matter? You already have an ace magic student who's way better than I'll ever be!”

“I'm not asking you to outdo Twilight Sparkle at magic,” said Celestia cooly. “I'm not unreasonable, Rainbow. All I ask is that you show up to your lessons.”

“Why? What's the point?” Rainbow snapped. “You know how much I suck at magic. I'll never be good at it!”

“Then at least be mediocre,” Celestia replied “The point is for you to gain the minimum degree of education expected from a pony of your stature, and that includes an adequate grasp of basic magical theory. That should be well within your ability just as long as you put some actual effort into it. Is that really too much to ask?”

Rainbow gritted her teeth, only barely restraining herself from stomping the marble floor in frustration. “You just don't get it!” she growled under he breath.

She hated magic. She would always hate it. Why couldn't her mother see that?

Why should I bother trying? I can never win against her.

...I hate losing.

Celestia silently regarded her daughter for a few moments, and then her features suddenly softened. She approached Rainbow. “I'm sorry.”

Rainbow looked up in surprise. “What?”

“This is not the time for us to be fighting,” Celestia said. “I only want what's best for you, but maybe I have been too strict with you lately. You've always been a free spirit, just like your father. Perhaps what you need the most right now is some time away from the court, to stretch your wings a bit?”

“You...” Rainbow's frown slowly turned into a smile. “You mean that? Really?”

“Really,” Celestia smiled back, but her eyes looked tired. “It's not just you, Rainbow. I've been... under a lot of stress lately, what with the festival and all. Consider this a peace offering.”

“Aw!” Rainbow impulsively reached out and gave Celestia a hug. “You're the best.”

Celestia chuckled. “It's decided, then. Tomorrow you may accompany Twilight Sparkle to Ponyville and keep her company while she makes sure he festival preparations are in order. She's a very diligent little pony, so you should have plenty of spare time to spend as you like until I arrive to raise the sun tomorrow. How does that sound?”

Rainbow cocked her head. That did seem like a great deal, but... “Aw, you mean I have to spend the whole day hanging around Sparkle?”

Celestia grinned. “Consider that your punishment for skipping classes. I think that's fair, don't you?”

“Heh, I guess it could be worse,” Rainbow admitted, smiling wryly. “Even though Sparkle's almost as boring as Professor Mandrake.”

Sighing slightly, Celestia turned to view another window. This one depicted a young Rainbow earning her cutie mark performing the sonic rainboom over Canterlot. “You know, when I first took on Twilight as a personal student, I was rather hoping the two of you would become friends.”

“Yeah, that didn't really work out, did it?” Rainbow said. “We have, like, nothing in common.”

Celestia shrugged. “There's more to friendship than sharing interests. Be that as it may, I'm sure you can put up with one another for a day.”

“Right,” Rainbow said. Her mother had that distant look again, probably remembering something from centuries before Rainbow's birth. “...So, do I really have an evil aunt locked away on the moon?”

Celestia blinked and turned to her. “Ah. Twilight told you about that, did she? She has her heart in the right place, but she worries too easily.”

“So it's true?” Rainbow asked. “I mean, I get that it was a really long time ago, even for you...”

“Has it really been that long?” Celestia mumbled, more to herself than to Rainbow. “Sometimes it doesn't feel that way...” She shook her head and smiled sadly at Rainbow. “I'm sorry. It's simply not a subject I like to bring up. Never the less, it is a family matter and you deserve to know about it. After the festival, I promise to tell you all about it.”

“Fair enough,” Rainbow said. “Man, tomorrow is going to be great! I already have an awesome idea for how I'm gonna do this!”

Celestia's smile turned slightly nervous. “Should I be worried? I seem to recall that last time you had an 'awesome idea', I ended up with a mob of rioting revolutionaries on my hooves.”

“Whoa, hey now!” Rainbow raised her hooves in protest. “That was a long time ago, and also a total misunderstanding.”

“Even so, please do try to stay out of trouble,” Celestia said. “I'd hate to find the town razed to the ground by the time I arrive.”

“Oh, don't worry,” Rainbow grinned. “They won't even notice I'm there!”

"You ████ ████ ██████! I'm going to █████ your █████ █████, you █████!"

"...What's a ██████?"

"I have no idea."