The door to the old wizard’s study creaked open and Celestia poked her head in. Master Starswirl was out on what he had said was important wizarding business. Which meant he did not tell her what it was that he was doing, but it was sure to take awhile. She had the run of the place, and she had no intention of letting this opportunity slip by.

If there was an Element of Curiosity, that would have been her. Of course there wasn’t, and Celestia did not even know what the Elements of Harmony were yet. In fact, today was the day she would first learn those words. And that word, Harmony, would write itself across her heart in blazing letters.

She would learn a lot of things today.

But right now, she only wanted to explore her teacher’s study and see if she could find out any of his magical secrets. Her motives were innocent. She was not a great magician. Why the greatest wizard of the age would have taken somepony like her for an apprentice was a mystery to her. She wanted desperately to impress him. And maybe, just maybe there was something in this study, like a secret spell that she could learn in order to prove to Master Starswirl that she really was worthy to be his student.

Worshipful awe settled over Celestia as she entered her teacher’s study. It was the concentrated form of the feeling that had been pulsing through her soul ever since the wizard had taken her on as his student a year ago. A year… had it really been that long? Already she could barely remember what her life had been like before that. As far as she was concerned, her life started the day Starswirl the Bearded took a ragged little unicorn from the streets of Canterlot. Before that day was—

Nothing. Nothing worth remembering.

A jar stared at her from the great desk in the center of the study. It literally stared. A bunch of eyes floated in clear liquid inside it like a cluster of grapes and watched her carefully. Celestia swallowed and looked away.

Her gaze fell to the bookcase behind the great desk. Some of those books were bound to contain magical secrets. A sunny smile brightened her features and she made her way around the desk.

“Hey!” a voice called to her. It sounded muffled, like it was coming from another room.

“Who’s there?” asked Celestia, her smile fading into a worried expression. Finding a secret spell and impressing her teacher was a good thing. Getting caught before she could manage it was not.

“Over here.”

Celestia looked. There was only a wall. And on that wall, mercifully covering a large oval patch of Master Starswirl’s carrot wallpaper, was a mirror.

“I can’t see you, whoever you are,” said Celestia.

“I’m in the looking glass,” said the voice.

Celestia stood in front of the mirror and peered inside. All she could see was her reflection, a white unicorn filly with a dull pink mane. Nothing special. There were a couple faint ink stains on her muzzle from her writing exercises. Those spells for moving quills with magic were harder to pull off than they looked. To her at least.

“I don’t see anypony but me,” said Celestia. Her reflection’s lips moved along with every word.

“You’re not looking right! Look harder, more magically. I’m right here!”

Celestia stared at the glass, focused on it with the same intensity that she used when she was casting a spell. Only unlike her usual pitiful attempts at magic, this time her intensity paid off. The image in the glass shimmered like the surface of a puddle. Her reflection was gone, replaced by a very different little unicorn.

“Hi!” the other unicorn filly said. She was dark blue, with a mane the color of the sky just before evening and large aquamarine eyes.

“Who are you?” asked Celestia. “And what are you doing in a mirror?”

The blue unicorn grinned. “I’m not a who. I’m a what. This looking glass was created with fairy magic. I’m a reflection of whoever looks into it. I guess you could say I’m kind of like a copy, created out of your magic.”

“Do you have a name?”

The reflection’s blue ears drooped. “No. I change depending on who looks into the glass. Today I’m a copy of you. Tomorrow maybe somepony else. I was created to be fluid. A name would work like an anchor for something like me. It would give me a single form.” She sounded wistful.

A pang of sympathy stung Celestia. Some part of her knew that she should be more careful. Fairy creatures were strange, and some of them dangerous. Like the changelings, a rare race that fed on love and could drain a pony of every drop of emotion until she was dead inside. But this creature, whatever she was, seemed good.

“I’ll give you a name, then,” Celestia announced.

The blue unicorn went pale. “Don’t! You don’t know what you’re saying. Names are powerful things. Magical things. They are not to be trifled with.”

“I wasn’t going to trifle.”

The fairy creature’s eyes narrowed. “What if I told you that giving me a name would be casting a spell. Half your life and half your magic would become mine.”

“I don’t have much magic anyway.”

“I said your lifespan would be cut in half too.”

Celestia averted her gaze. “Well, I’m young. It might not be so bad…”

The blue unicorn filly’s mouth dropped open and her eyes widened, sparkling with the sudden threat of tears. She tried to say something, then clamped her lips shut and shook her head. The mirror’s surface shimmered again and Celestia was left staring at her own reflection once more.

“Don’t ever say that again,” the blue filly’s wan voice came from the glass. “Never again.”

“I’m sorry,” said Celestia. “I just wanted to help you.”

There was no reply. Celestia looked down at her hooves. She’d messed things up again. Was there a kind of magic she wasn’t a complete failure at?

As it turns out, there was. It was the most powerful kind of magic of all. The moment she made her offer to the little pony in the glass it began its work. And like a seed planted, one day it would bloom.

Celestia continued to speak to the mirror but the pony in the glass, whatever it was, did not return. Alone once more, she returned to searching her teacher’s study.

The bookcase behind Master Starswirl’s desk was crowded with dusty texts. Any one of them might contain the magical secrets Celestia was looking for. There were all seven volumes of Unicorn History, Commander Hurricane’s Airborne Warfare, one of the only known copies of Clover the Clever’s The Heart of Magic, and Master Starswirl’s own Elements of the Arcane. There were many others. Celestia flipped through The Windigo Prophecy, A Catalogue of the Spirits of Chaos, The Canterlot Tales, A Tartarus Field Guide and even Changeling Sorcery. There were dozens of books about magic and the history of Equestria and all the fantastical creatures that lived in the Everfree Forest. But none of these seemed to hold the magical secret she yearned for in her heart.

She glanced up at the desk. Several scrolls hung over its edges. Celestia jumped up into his chair for a better look. Two books rested on top of the scrolls. They both looked ancient. A half-finished letter was rolled up next to an hourglass with black crystal sand pouring through it in reverse. The floating eyes in the jar followed her every move as she picked up one of the books.

“The Book of Harmony,” she read aloud. As if she had cast a spell, the air in the study grew warmer. She tried to magic the book open, but couldn’t even manage that simple spell. Frustrated, she swatted at the book with her hoof and flipped through its pages.

The torch that stood in the corner of the room near the bookcase flared brighter, making it easier to read. “The most powerful magic known to ponydom…” Celestia’s voice was a whisper. Her lavender eyes lit up as she read the legends of the Elements of Harmony, which were supposed to be the key to magic. The words Harmony and friendship appeared over and over again.

She read through the entire book, losing track of time.

At last she sat the book down, a satisfied smile on her face. This was it, this was the magical secret that she had been searching for. Harmony. Why hadn’t Master Starswirl ever talked about it before? The word seemed to expand within her, filling her entire being with light. From this moment on, she would learn all she could about Harmony and the kind of magic that was born from its power. She would teach its secrets to generations, and one day she would know it more intimately than any pony in the world, with the exception of one.

“Friendship is magic,” she said out loud. It was the first rule of magic, according to The Book of Harmony. Real magic took more than study and practice. It required friendship.

Celestia’s only friend was Starswirl. He was the one who took her in when the rest of the world had turned its back on her. He made her his student, taught her to read and write and do magic. If magic needed friendship to work, she had all she needed. As she concentrated on what the old wizard meant to her, her heart lifted. She felt like she could do anything.

Heart in the clouds, she used her magic to float the other ancient book over to her and open it. She cast the minor spell without so much as a hiccup. Yes! she thought. Yes, yes, yes! It’s working! I’m doing it! She kept her composure, afraid to break the spell.

The torchlight dimmed as she pronounced the name written on the book’s cover in deep ruby letters: “The Sea of Night.” Celestia glanced at the flickering torch. But it wasn’t a torch at all.

It was a bird. A bird made of fire.

Celestia knew what a phoenix was. She had read about them. Why hadn’t Master Starswirl ever told her that he had one? The phoenix ruffled its flaming feathers and peered at her with one blazing orange eye. Somehow she felt even more uncomfortable than she did when the jar of floating eyeballs was watching her.

“Hello,” she said.

The phoenix chirped something in reply.

Slowly, Celestia lowered her gaze from the phoenix’s and started reading the book she was levitating over the desk. But as she read, an uneasiness began to fill her. The Sea of Night was nothing like The Book of Harmony. There were secrets in this book, but not the kind Celestia was looking for. What was Master Starswirl doing studying a book like this one? Everything it said about magic felt wrong. A grim suspicion grew in her mind and a frown began to form on her face as she read, lavender gaze scanning page after page. Dark secrets unfolded themselves before her, like black flowers blooming in the shadows. A bit of the light went out of her eyes as she read, and the book wobbled in the air as her spell weakened. Her expression remained stoic as she turned the pages, as if her face had been chiseled from marble, but her heart raced. And her blood ran cold as she came upon a name that was only written once in the entire book. Every other word in the text was written in smooth, flowing ink. This one was written as if the quill that scrawled it trembled. Cauchemar. The Arch-Enemy of Friendship.

The levitation spell broke and the book tumbled from the air onto the floor with a thump. Celestia’s dull eyes fell upon the rest of the scrolls on the desk. The dark suspicion that had taken root in her heart drove her. She didn't want to believe it, but she had to know. She read every scroll. This can’t be true, she thought. Then she read her teacher’s half-written letter. His weary quillwriting was unmistakable. When she was satisfied, she sat down in the wizard’s chair and waited.

After only a little while, she heard the bells.

“What have we here?” his rich voice queried when he noticed the door to his study was open. He entered the room.

Starswirl the Bearded had lived for more than a century and looked it. His grey fur was a wrinkled map that charted the experiences accumulated over a hundred years. He wore a cloak and pointed hat embroidered with astrological signs and constellations. Bells hung from their rim and fringes. There was a legend that the bells he wore once decorated the cloak of the arch-mage of Tartarus, whom he had defeated in a wizard’s duel that lasted a week. The sounds they made were said to ward off evil spirits. Or was it summon them? Who could remember these things?

“Celestia, my faithful student,” he greeted her.

“Starswirl,” she said. Not ‘Master Starswirl’ as she would have before. Never again. Her voice was iron. It was the same tone she would one day use when sentencing criminals.

“What are you doing in here?” he asked. His own tone of voice was not unkind. Nothing about him was unkind, ever. Not even his cruelties.

“I know everything,” she said.

“I very much doubt that,” said Starswirl, amusement glittering in his eyes.

“I know what you’ve been planning, I mean.” The books and letters had revealed everything to her, his whole dark scheme. And there, sitting in the shadow of his plan, terrified by its scope, there had been only one thing she could do.

Starswirl nodded slowly. “And you disapprove.”

“I do.”

“Whatever for? Even isolated from the world as you have been lately, you know what has been happening in Equestria for generations. War. The tribes have been at each other’s throats since the days of Princess Platinum. My plan might seem cruel to a filly who has been raised on fairy tales, but it will save lives in the long run.”

“Liar. You’re going to ruin everything.”

Starswirl took a step toward her. “Do you think I left my notes and letters out in the open by accident. I wanted you to see them. To give you a choice.”

“It wasn’t a choice at all! Do you think there was even a chance that I could have sided with you against the rest of Equestria?”

“Of course. You are a unicorn, a child of magic. Born to rule.”

Celestia shook her head. “I don’t want to rule anypony. I want the tribes to live in harmony.”

“Harmony…” Starswirl sneered. For a moment it seemed as if he wanted to say something more, then he seemed to change his mind. “What does it matter? I have lived long, child. When you have a hundred years behind you, let us see whether you still believe in the power of Harmony.”

“I will! I would if I lived to be a thousand!”

The old wizard smiled sadly. “Oh Celestia, my precious student. So be it. You said you didn’t have a choice. I give you one now. There is nothing you can do to stop me. My followers and I will bring all of Equestria to its knees. The pegasi and earth ponies will fight, of course. They will bring their earthquakes and their storms, and blood will be spilled… but in the end, they will kneel. I go to war. Join me or you will discover how merciless I can truly be.”

“I already know that,” Celestia whispered. “When I said I knew what you were planning, I wasn’t talking about your plan to win the war between the tribes. I meant that I know what you’ve really been planning.”

Starswirl’s red eyes searched her. “You do, don’t you? Interesting. You are the first, then. I am not surprised. You have always been brighter than you gave yourself credit for.”

Celestia’s voice cracked. “I can’t let you do it.” Her heart ached. Warm tears welled up in her eyes.

“You cannot stop me. I have powers you cannot even imagine. Even if you brought every drop of your magical power to bear against me, it would not so much as give me pause.”

Celestia wiped her nose with a hoof. She forced her voice to remain steady as she said, “I challenge you to a duel.”

When she was living on the street, Celestia learned that anything could be stolen, even your life. Back then, she had retreated into herself and found there the one thing that nopony could ever take from her. Not then, not now. Starswirl could take away her life. He could not take what made her who she was. It burned at the center of her, a flame that could never be quenched.

One of Starswirl’s white eyebrows raised. “A duel? Stop this foolishness, Celestia. You don’t stand a chance.”

She knew that. It didn’t matter.

The little unicorn leaped onto the desk and locked eyes with her teacher. “I will die before I stand by and let you have your way.”

The old wizard sighed. “Very well. A duel it is. The stakes?”

“All that is.”

“Then you do understand.”

The two unicorns faced one another squarely. Their horns began to glow with eerie light. For a pregnant moment, neither one of them cast. They just stared at one another, something precious and unspoken passing between them.

Celestia cast first, but there was a flash of purple light and a noise like a thunderclap as Starswirl’s magic discharged. It blew through Celestia’s puny spell as if it were nothing, striking the filly in the chest and knocking her off the desk. Books and scrolls went flying. The phoenix flapped its fiery wings and shrieked.

Then it was silent in the study. Celestia’s body lay sprawled out on the floor, her lavender eyes wide open.

Starswirl stood over his apprentice’s warm corpse and looked down at it, his expression unreadable.

“Farewell, my faithful student,” he whispered. Then he went his way unhindered, to make war.

A stillness settled over the room in his absence. The body of the little white unicorn grew cool on the floor.

The phoenix looked down at the little pony for a long time. It seemed thoughtful. Eventually the creature made its decision. It flew down to Celestia’s body and covered her with its wings. Flame engulfed both of them. Then the fire spread across the floor, over the desk, crawling up the walls and the bookcase. Everything burned. The entire study was an inferno. Swirling orange flames crackled and roared.

In the heart of the blaze, a flash of pure white.