It was your average summer día in Ponyville, the sun beaming down on everypony's cheery faces as they did their life's work. It didn't seem like there was a great disturbance of any sort, smiles lighting up the expressions all over town. Well, except with the weather team, who were interrupted por a falling filly...
    “One, two, three, four!” arco iris Dash chanted, bucking wildly at clouds. She was giggling to herself, absolutely having the greatest adrenaline rush she could possibly conjure. The rápido, swift pegasus poni, pony suddenly locked her gaze onto the biggest nube in the sky, hovering above Sweet manzana, apple Acres.
    She chuckled and arched her legs up, ready to give the great puff of condensed rain what was coming to it, when suddenly, a bright green poni, pony from up above ruined her fun por taking a deep nosedive through it.
    “Hey, what gives?” Dash jeered, narrowing her eyes at the downward spiraling pegasus, who she immediately assumed was attempting a daredevil stunt. Dash noted little details about her- her black mane, her mane's electric blue streaks- except one crucial one.
    The strange pegasus had her eyes shut.
    Rainbow Dash heard a loud thud echo from the ground, and then sudden silence. She paused for a moment, unable to grasp the situation, then finally grabbed hold of the reigns of her mind.
    “Oh no...” Dash mumbled incoherently, taking a sharp dive into the trees of the manzana, apple family's orchard.

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    Applejack was casually sauntering through the manzana, apple orchard, wheeling her carro of the specialty frutas behind her. She whistled, caught completely unawares when a neon filly landed with a loud BAM!
    “What in tarnation?!” aguardiente de manzana, applejack exclaimed in a fluster. She stared at the unconscious carcass of the stranger pegasus.
    In a quick swoop, arco iris Dash frantically screeched to a landing siguiente to Applejack.
    “Apple...jack...pegasus...fall...sky...cloud...” Dash panted, out of breath from her anterior lightspeed pace.
    “Rainbo' Dash, calm down. Can ya explain what happened here?” aguardiente de manzana, applejack dicho in a collected voice with a hidden tinge of worry.
    “I dunno, she just.. fell! From out of nowhere!” Dash explained hastily.
    “Well, alright, let's get this here poni, pony to Nurse Redheart,” aguardiente de manzana, applejack inquired, setting the injured poni, pony on parte superior, arriba of the piles of apples, carting her to Redheart's clinic with a not-so-merry spring in her step.

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    The strange poni, pony flickered open her pale blue eyes, jolting up in a painful strike. She twitched her wings, and found one unmovable, placed in a stint. Her front left leg was also stinted, and she groaned in complaint with her inability to move. As the stranger's eyes came into focus, she witnessed about a dozen ponies surrounding her, including Nurse Redheart.
    “Are tu feeling any better, dearie?” Nurse Redheart piped up. The hurt pegasus replied with another groan of protest.
    Rainbow Dash began nudging through the crowd of ponies, with the occasional “Hey!” o “Excuse me!” emanating from it. Dash placed her front hooves on the cama she was lying on, her face wrinkled with concern and some form of regret. aguardiente de manzana, applejack politely scrunched up siguiente to her, giving the neon poni, pony a sweet, relaxing smile.
    “Are tu okay? I'm so sorry I didn't catch you! I thought tu were pulling off a trick o something!” Dash blurted, unable to contain her guilt.
    “I-it's... okay...” she spoke softly in an angelic soft voice. She gave a solemn smile, but it was más mourning than relieving.
    “What's yer name, sugarcube?” aguardiente de manzana, applejack asked.
    “D-Dusk...Dusk...” she mumbled, unable to finish.
    “Dusk what?” Dash pushed, trying to convince her to conceal her full name.
    “...I...don't...remember. Just... Dusk...” the filly complied.
    “Well, okay then, Dusk,” Dash muttered, rolling her eyes. aguardiente de manzana, applejack elbowed her lightly, and Dash sighed in capitulation.
    “Excuse me, everypony, maybe it's time tu all get back to work,” a purple unicorn from the crowd suggested. As the others came to the same conclusion, they parted from the scene, giving the unicorn pony, Twilight Sparkle, the right away.
    “Hello, Dusk,” Twilight greeted with a sincere smile. “May I ask tu a few things?”
    “S-sure...” Dusk replied uneasily.
    Twilight, nodded, cleared her throat, and filed up straighter than she already was.
    “Do tu remember what happened to make tu fall out of the sky?”
    “N-not exactly...” she mumbled.
    “Do tu remember anything that happened before the incident?”
    “N-no...”
    Twilight sighed in submission. “Well, if tu have nowhere to stay... my inicial is always open to you, tu can room until tu heal,” she offered.
    Dusk simply nodded, unsure of how to reply.
    “Well, alright then,” Twilight finalized. Dash and Applejack, who were still at Dusk's side, helped her hobble out of bed, and steadied her as they ventured towards Twilight's library.

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    “Thank tu again for letting me stay here,” Dusk comentó for the third time since she had arrived in the cozy home. She was eating cena quietly to herself, while Twilight was lectura por the fireplace. Spike was asleep on the ground por the crackling glow, snoring lightly.
    “Really, it's my pleasure,” Twilight assured, “You can stay here as long as tu need to. Besides, Ponyville is a very nice place, tu should get to know the ponies around here. They're all very kind and friendly.”
    Dusk sat in an awkward silence until she finished her meal, and stumbled from her seat. “I'll just be...headed to sleep now,” Dusk dicho in a fake attempt at a tired voice.
    Twilight glanced up from her book once more. “Can tu make it up the stairs por yourself?”
    “Um, sure,” Dusk answered in a wobbly tone. She leaped up the staircase on her hind legs, holding onto the el maletero, tronco that made up the walls for support. As she fumbled up the stairs, Twilight watched her moves to make sure she wouldn't fall, and her eyes set upon Dusk's cutie mark- a black corazón with an arrow through it.
    “Wait, Dusk?” Twilight called out, standing from her chair, making her way to the staircase's edge. Dusk swiveled around on her back legs, wearing a confused expression.
    “Um...yes?” Dusk responded shyly.
    “Your cutie mark... what does it mean? I've never seen anything like it... it's sort of... sinister, don't tu think?” Twilight criticized.
    Dusk stood in silence for a whole minuto it seemed, gazing into Twilight's eyes, as if staring into her soul. Dusk shook her head when she came back to her senses, but remained a serious, unwilling look.
    “Good night, Twilight,” she retorted firmly, before wobbling up the final steps and entering the guest room.
    Twilight tilted her head, and stood dumbfounded.
    “What... just happened?”

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    After settling into the guest bed, Dusk lit a candle and placed it on the nightstand siguiente to her. She sighed and stared at her cutie mark, which was a depressing pitch black.
    “You almost blew it just now, Dusk. tu need to cover up your cutie mark siguiente time tu go out,” she muttered to herself. She chuckled a little before speaking again.
    “If they knew who I really was...” she continued, “They would be sorry to be so casual in my presence.”
    She quickly forced the candlelight out with a flurry of breath, and rolled over, resting her eyelids over her pale blue irises, entering a world of dreams.

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    Twilight Sparkle, however, sat wide awake, extremely curious. She shuffled through a thick, musty book labeled “The History of Cutie Marks.” Twilight began to speed read through every page, getting más and más frustrated with a lack of information.
    “No...no, no, no! Gah!” she huffed, about to give up. She angrily flipped the page, scanning through, and came across a bold underlined subtitle. Her eyes popped a smidgeon, and she began to read the text under it intently.

    Shadow Marks

    Shadow Marks are the evil equivalent of Cutie Marks. Shadow Marks appear to be pitch black in color. In ancient Equestria times, all ponies had what was called an alter ego, o another side, which actually took their forms; each poni, pony in existence had a segundo being. The negative emotions of ponies were channeled through these alter egos. However, the alter egos of everypony in Equestria joined together and overtook the princesses, and swarmed the land with plague and sin. However, the Elements of Harmony pushed away this evil force, and used its power to cause all alter egos to merge into their original poni, pony forms, hence the ponies tu see in present day.
    However, por the philosophy of the famous philosopher poni, pony Aristrotle:

    “Evil can never be put to rest; it can only be hidden.”

    Therefore, it is unknown when, but there has always been a rumor of the return of the destructive alter egos. However, as this was never proven, it was forgotten in the lengths of Equestria history. But, amongst skeptics exist apocalyptic paranoids, and sometimes mistake ponies who simply earned black marks to be resurrected alter egos, and attack them without proof o cause.

    Twilight gawked at the page for a while in contemplation. She started to piece together bits of what she had read and wondered if it was a plausible fit.
    “Her mark... was black... and her behavior earlier was a tad bit odd... oh, come on, Twilight, tu read that last part. Maybe tu need to stop jumping to conclusions...” she argued with herself. She exhaled deeply, and stacked the book back in its place on the shelf.
    “I probably just need some shuteye...” she persuaded. She got a glimpse of the snoring baby dragon on the floor, and snickered a little.
    “I'll just leave him be,” she decided, lifting a blanket twisted up in a chair with her magic and layering it over Spike. He curled up into it, making Twilight smile. She then cantered up to her accommodations to have a sound night's sleep.

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Should I continue?