"Please... not this again." The words barely whisped away from Twilight Sparkle's mouth, too fragile to carry themselves across the open air. The landscape at her hooves was foreign, yet intimately familiar. An open field that stretched far beyond any Equestrian horizon. Perfectly trimmed blades of grass, shimmering in reflected hues of purple and scarlet. A sky cracked open, alive and bleeding. A single glance upon it, and the heavens would swallow up even the most grounded and conceited of ponies. Lost forever in the great swirling cosmos abroad.
Twilight squeezed her eyes shut, and pressed her head into the ground. She could feel each blade of grass, as they tickled at her nose and cheeks. But they had no scent. Nothing had a taste here; nothing had a smell. Everything was just a feeling, a little voice in the back of her head, gently urging her toward the sky.
"No!" Twilight tried to scream, but it came out as less than a whimper. Her flank began to tingle, like somepony was holding ice against her cutie marks. "W-what d'you w-want from me?" The tingling erupted into an itching, burning sensation. Twilight's legs buckled and the hairs on her back stood on end. Nothing escaped from her lips beyond an unintelligible squeal. She frantically started digging at the ground; anything to escape, anything to take her mind off what was going to happen. It felt like the skin on her rear was bubbling and pulling away, while the flesh beneath it boiled and seared. Pain rippled up her spine and washed upon the shores of her body, from the tips of her ears to the tiny crevices of her hooves. Twilight collapsed on the ground, shaking violently and drooling vomit. Her unicorn horn was throbbing, pulsing to the beat of the sky above. Tears forced themselves from squinted eyes as her mind ripped itself to shreds.
She fought it with every ounce of strength and determination she had, taking the pain with gritted teeth. But it was a losing battle. Her horn split open, impregnated with the origins of a spell she did not know. The ground shook beneath her, breaking at the seams. Every ounce of pain, every fear, every doubt, everything she knew and didn't know drained from her body and filtered into her horn, collecting there and adding to the violence of the torrent about her. A force beyond her control took hold of her. It slowly, deliberately opened her eyes and lifted her head from the ground. As her gaze met with the heavens, her horn broken open and shot a spell deep into its heart.
Twilight Sparkle burst out of her covers, panting and gasping for breath. Her body was soaked in sweat and shivering despite the mid summer's warmth; cutie marks throbbing with a dull and subtle pain. The clock on the wall told her what she already knew. She hadn't slept a minute more than three hours. But she couldn't submit herself to slumber just yet. She craved a book to read, a friend to talk to, anything to take her mind off the reoccurring nightmare and the shameful secret it held.
"Get a grip on yourself, Twilight Sparkle. Dreams are just dreams, and they can't hurt anypony." Twilight wanted to believe what she said, but her heart just wasn't in it. She thought back to the likely culprit of the dream, her advice to the Cutie Mark Crusaders that very day: "Try something you're already good at to find your cutie mark." The words, insincere and ironic, left a bitter taste in her mouth. Twilight envied those empty headed blank flanks. They would find their special talent, and they would build their lives around it. Their talents were already so painfully obvious to everypony anyway.
"Don't be bitter, Twilight."
Twilight huffed. Every book always said the same thing: a pony first discovers her special talent, then the cutie mark appears. Then and only then. It's like a contract with the Universe, sealed in flesh, plastered on a flank for everypony to see. Twilight sighed, and looked down at her own flank. Why was she different? Twilight Sparkle still had no idea what her special talent was, and feared for the worst. As she laid her head back down on the pillow, her thoughts ventured back to the days of youth. Back in Canterlot, before she was Princess Celestia's prized pupil. When she was just an awkward, lanky, bookish filly, taking the same classes every other pony her age. But she was the top of her class; the kind of pony that made all the other ponies look bad. And they knew it. Keeping up with her reputation, she was even the first to get her cutie mark.
It just wasn't what she expected.
Twilight was hopelessly obsessed with finding her cutie mark. She read every book on the subject she could get her hooves on. Statistics of cutie marks, correlations of special talents across sex, species, and economic standings. A young unicorn's guide to magical cutie marks. Finding the cutie in you. The contents didn't matter. Every turn of the page made Twilight feel closer to finding that special meaning of life. She was convinced it would be related to her favorite subject: magic theory. She envisioned herself buried in arcane tomes, traveling across Equestria to explore uncharted magical sources, unraveling the mysteries of magic locked within time and space itself. A lofty goal for a pony that rarely stepped outdoors, but it was a filly's dream.
Everypony told her that she had her head in the stars.
It happened on an ordinary night. Twilight finished her Equestrian history report before dinner, so she could spend the evening with her latest volume on cutie marks. There was nothing particularly special or inspiring about that book; it was just an over-glorified self help for the low esteemed filly. But it still felt good to read material that reaffirmed what she already knew. When it came time for bed, she didn't protest. She didn't hide under the covers, in a magically illuminated after-hours reading session. She set the book aside, and let the dark cloud of unconsciousness overtake her.
That was the first night she had the nightmare. The dream that felt as real as any waking moment ever had. The dream where her body was set aflame by magic she could not control, bading her to crack open the night sky. The dream where, deep in her heart she feared, that she destroyed all of Equestria and everypony she ever loved with it.
On that night, when she woke up crying and sitting in her own fresh urine, she had her cutie mark.
She had to make up a story. She would tell everypony all about how she was tracking the known constellations on her free time. About how as soon as she spotted the last one, the cutie mark was sitting on her rear. They would believe it. They had to. Even her name, Twilight Sparkle, reinforced the idea that she should be some kind of space nut. But the truth is, whenever Twilight looked down at her flank, the only thing she saw staring back at her was a gaping hole in the sky.
A bittersweet tear rolled down Twilight's cheek. The nightmare has followed her through the years, ever since that fateful night. Countless hours spent behind books, from classic astronomy to crazy pony tales of the coming apocalypse, and she still didn't have the answers. But the only thing she knew for sure is that she wouldn't stop searching, she wouldn't rest, until she knew the truth behind her special talent.