"Uuuungh..."

The loud groan made the farmpony's ears twitch. She thanked her last customer and turned to look at her friend, who was stumbling about with a look of strong discomfort on her face.

"Y'all right there, Twi?" Applejack said.

"Yeah, I'm just... Ugh..." Twilight sat down and rubbed her belly with her foreleg. "My stomach's not my best friend today..."

"Somethin' ya ate?"

"Not much since yesterday..."

Applejack stepped closer to get a better look. "Whoa... Ya look a lil' green around the gills. Maybe ya should go visit a doctor."

"Nah, it's not that bad..." The unicorn chuckled. "I guess even Fluttershy's cooking can be a challenge sometimes."

"Oh, that?" Applejack laughed as well and patted her friend's back. "Heh, gave me a few nasty dreams last night. Still, it was some good eatin', right? I'm sure it'll pass."

Twilight sighed, her hoof still massaging her stomach. "Yeah," she muttered. "I guess so."

"Ya know, maybe ya should have used yer magic after all," Applejack said. She went back to her stand to dismantle it and prepare the parts for the journey home. "Carryin' all those big loads and whatnot. Big meal after hard work upset yer stomach? Wouldn't surprise me..."

"Well, how else am I supposed to stay in shape?" Twilight said. She trotted up next to her friend and helped her remove the sign from the stand. Her eyes twitched as her horn lit up to remove the screws, the effort of using magic seeming to pain her today. "Besides, spring cleaning is way more fun without advanced magic. It means it's something we can all do together, same as Winter Wrap Up."

Applejack lit up. "Hey, that reminds me: don't ya got some kind of spell that could help you?"

Twilight shook her head, the glow on her horn fading away. "I can't fix every problem with magic, Applejack. If I don't let my body heal itself, it will never be ready to face trouble in case my magic fails somehow..."

"Ah see what ya mean."

Twilight's face contorted, and another tiny belch left her lips. "On top of that... I don't actually know any healing spells."

Applejack blinked. "Wait... Seriously? Ah thought you were like a whole library of spellbooks on four legs..." She scratched at her head and chuckled nervously. "No offense."

"None taken." Twilight groaned and let out another belch. She did not even try to hide it this time. The relief was all that mattered. "Ugh... Pardon me. And no, skill in unicorn magic is not universal. It's not as simple as 'learning a few spells'."

"Like how work on mah farm ain't just about kickin' trees real hard, right?"

"Exactly. Most of the things you see me do are thanks to me practicing them my whole life. If I wanted to heal ponies, I'd have to spend years in a medical school first."

Applejack smiled. "Well, if unicorn magic can't help, want to try the earth pony way instead? Ah'm sure Granny Smith has a few recipes that could help."

Twilight hesitated for a moment, but ended up returning the smile. "Sure, why not?"

Twilight awoke with a low groan. Her eyes sluggishly opened, only to close again quickly from the morning light that seeped in through the blinds. A crushing agony descended on her skull, making her groan again as she rolled back and forth on the sweat-soaked cushions.

She belched, and the bitter smell of the odd concoction she got from her friend rose up from her belly. Last time I ever drink "Granny Elixir" before bed... she thought.

Twilight frowned. Something was very wrong. Not that she felt sick; the nausea did not get any worse. Then again, it did not get better either, and she now had a slight headache, as well as a soreness in her throat, plus a weird tingle in her forehead. But other than all that, she felt fine. Probably just a bad night's sleep. Still, something kept nagging at her that things were about to get very bad, if they had not already.

With a sigh, she sat up, gave a long yawn, and climbed out of the bed. A quick shake of her head brushed away her concerns, though the ache and nausea remained. Her hooves slowly dragged her in front of the mirror nearby, where she summoned her brushes and combs for her daily grooming process.

Once she finished washing her face, brushing her coat, and making sure her mane and tail were both in order, she looked herself over, a satisfied smirk on her face. Already the mild aches and sickness seemed to be fading away as a result of her routine of tidying herself up. She gave a pleased sigh and was about to turn away when her eyes caught on something.

"What the hay?" she muttered.

Just at the base of her horn, she noticed a slight bulge under her skin. Twilight's eyes narrowed, and she leaned a bit closer to the mirror. At first, she thought she was just seeing things, but the bulge was still there after several blinks and wipes of her eyes. She reached up with her forehoof to touch it, only to gasp in surprise and freeze when the bulge seemed to move, followed by an odd tickling sensation at the same spot.

An odd lurch passed through Twilight's insides, all the way up through her throat, and the feeling of dread from before now returned with a vengeance. Moments later, she watched, wide-eyed, as more and more of her scalp around her horn bulged slightly, the tickling sensation intensifying along with them.

Twilight gasped again when the tingling spread to her horn directly, and the paper-thin layer of skin that coated the appendage bulged as well. It started at the base, and what looked like a small tentacle appeared under her skin and snaked its way up from the swollen area.

"Oh my gosh..." she whimpered. The tendril slithered further along the edge of her horn, pushing up the skin along the way. Her blood ran cold as she felt the thing rub against the bare bone and tissue underneath. "What is that? What is that oh my gosh Celestia help me..."

The tumor-like blob in her skin followed after the invading tentacle. It wrapped around her horn and slowly inflated under every inch that the lead tendril gained. A sickening sensation added to the odd tingle as her skin stretched, along with the feeling of someone wrapping fleshy fingers around more and more of her horn, their grip tightening with every passing moment.

Twilight gasped for breath, her heart pounding in her chest. Instinctively, she tried to use her magic, but all her horn could manage was vomit a few sparks from the tip. She tried again and again, but once the intruder moved a bit further up, she was unable to get a reaction at all. She could only stare in horror now, convinced that it was just a bad dream.

"...what the hay is that oh celestia get it out get it out of me please somepony help..."

She almost bit her tongue when the tentacle, now halfway up her horn, made a more rapid move and advanced a whole inch in the blink of an eye. The bulge followed it, and just under the thin membrane of her unnaturally stretched skin, Twilight noticed a flash of bright green slide along the inside of her appendage.

The tentacle pushed again and managed to reach the tip of her horn, the bulge rushing to catch up. The stretching was akin to someone trying to stuff her horn to bursting, and her skin felt close to a breaking point.

Twilight was too scared to move. Too scared to speak, or even blink. Her eyes remained glued to the sickening invasion, where the greenish presence from before was lighting up all around her horn now. Starting at the very base of her horn, her scalp had swollen out, filled to the brim with the bright green intruder, effectively smothering the appendage.

"...dear merciful celestia no this is impossible this is..."

Her hooves shook uncontrollably as she backed away from the mirror. The slightest twitch sent shivers down her spine as the tension in her scalp grew rapidly. The thing inside her horn had inflated the skin to over twice its volume, and it showed no signs of stopping. The membrane of skin inflated well beyond the fine tip of the bone to form a dull, rounded growth. It looked as though some translucent, balloon-like mockery had replaced her horn, though she could still catch a faint contour of the organ underneath.

Moments later, the swirling colors coalesced into a row of blurry stripes, arranged in alternating shades of green, while what looked like blots of ink collected near top of the growth, forming a pair of eye-like dots at the very tip. The swelling peaked, at which point the intruder stopped abruptly.

Twilight breathed hard. The grotesque image seemed impossible, yet the intense sensation convinced her that it was real. Her skin felt ready to burst at the slightest motion. Although there was no pain, the horrible tension in her scalp had her believe that it could rupture at any moment, which left her paralyzed with fear.

"Help me oh my gosh help..." She was finding her voice now. The intruder had stopped moving, but that was little comfort for her after all it had achieved in less than a minute.

If I let it keep going this way...

A million instincts fought for control at the same time. She wanted to run. To rip the thing out of her. To carefully go downstairs and seek help. Her legs remained rooted in place.

The thing inside her horn twitched.

"Help..." She tried to shout, though only a desperate whine came out. The thing twitched again and again, creating a horrible slimy sensation under her skin. Twilight's heart was beating in her throat now, but she was determined to squeeze her voice through. "Help! HE—"

Her scream was cut off and turned into an low gurgle, her gaze just able to catch the striped pattern of the creature pulse under her skin before a powerful rush of nausea and vertigo overwhelmed her head. Her eyes crossed as she felt something thick and slimy pump straight down from her horn and into her skull, only to squirm around a bit and pull back. A sickening lurch passed all the way through her body in response, her insides crawling and twisting into knots.

Twilight gagged, her forehead and nose throbbing as though she had managed to vomit part of her brain out through them. She gasped for breath and struggled to keep her balance, her eyelids blinking away at stars and black spots as she tried to refocus her vision. With a great effort, she managed to lean on the vanity and lift her gaze at her reflection, just in time to see the thing move again.

The mare fell away from the mirror and doubled over, eyes rolling back in her head as she gurgled more violently. Her body shook uncontrollably as the sensations returned even stronger. But the thing did not even wait for her to recover this time. Twilight heaved as the second pulse came, a small puddle of bile exiting her mouth, and it felt like her skull and intestines came out as well. A third pulse came just as she desperately tried to right herself and escape. Her legs gave out in mid-stride, and she fell against her bed. The fourth made her bladder release, or at least what little was left in it.

Bit by bit, the intruder built up a slow rhythm. Twilight was on the verge of blacking out, her body all but numb from the overdose of discomfort. There was still no genuine pain, just the same sickening pressure throughout her, not unlike the one in her horn. It blocked her ability to even think, let alone act. She could vaguely feel the creature slither back and forth, pushing its slimy mass in and out of her now empty-feeling skull. Her nerves, entrails, and veins all spread the vile feeling to the rest of her body. Her limbs twitched and jerked uncontrollably, and she had a constant urge to empty herself from every orifice.

After about a minute of this relentless torture, the motions of the intruder finally calmed down a little, and the violent reaction in Twilight's body lessened enough to allow her to breathe properly. Her hooves held on to the bedpost for dear life, and she gasped for breath, limbs and insides still twitching. Weakly, she pulled herself up enough and managed to turn her head to look at the mirror again. The thing inside her horn calmly pulsed back and forth, the green stripes and dark spots sliding along the inflated skin. She could feel the tiniest motions, the slimy flesh hugging her horn and throbbing in her skull, and the nausea and pressure it spread through the rest of her body.

Oh Celestia what is it doing to me why—

She gurgled and fell to the floor, mind going blank as the pulsing intensified again. It stopped a few seconds later, relieving the pressure on Twilight's mind and body.

What was that why did—

It came again. Twilight emptied the rest of her stomach's contents onto the floor. Like before, the thing relented quickly, but as soon as she tried to form a coherent thought, let alone start panicking inside her head, it "chastised" her again. At one point, out of pure instinct, she tried to make a run for the stairs. After another minute of gurgling and convulsing on the floor, it finally let her go once more.

Twilight breathed hard once her limbs managed to calm down. Tears streamed from her eyes as she sluggishly pulled herself back onto her haunches. Her mind was quiet and numb, held down as a reflex to the punishment she got every time. Instead, every thought was replaced by the constant squirming and slithering of the thing in her horn. The slimy noise became a constant drone in her skull. She shuddered and whimpered helplessly, but couldn't even think about why she did so.

For a couple of minutes, Twilight just sat there, the parasite pulsating in her forehead calmly. Her mouth hung open, making her drool all over her forelegs, and her eyes stared blankly ahead. She tried to "resurface" again, to comprehend what was happening, but the thing easily pushed her back down, eliciting a small groan each time. What little remained of her mind's functions now tried to experiment, or rather: blindly claw at the boundaries set up by the intruder to see what she could still do without resistance.

Her limbs jerked, and she attempted to move them around. The invader's movements remained the same. She tried standing up and marching a few paces in no particular direction. Still nothing. Content with having this much freedom, Twilight marched about akin to a feral creature, eyes glazed over and mouth agape, drooling. Her legs seemed to cooperate just fine, able to keep up a steady pace without stumbling, and they could even avoid obstacles and move up and down stairs. All they lacked was an actual goal to move toward.

Twilight tried to direct her vision next, but apart from just looking straight ahead, half-focused, she was allowed little more. Moving her mouth, let alone forming coherent sounds with it, was also right out. The very attempt of coming up with a message led to swift punishment.

She spent a couple more minutes testing her boundaries. The rest of her senses and most of her basic functions seemed to be unaffected, but that still left her at the invader's mercy. She would have sighed in frustration, but the emotion could not form. Her mind could still experience sensations, but it could not comprehend them on any higher level. It was empty and quiet, dominated by the noise and the feeling of the parasite's movements.

"Uuugh..." She twitched and gurgled when another burst of discomfort came. It was different this time. The thing pulsated a bit faster, but not in an effort directly against her. It was excited by something, and that led to yanking on her choke chain.

As her head lifted up, she noticed that she had managed to wander near her window, and the sunlight from outside washed over her. The parasite immediately reacted. The discomfort in Twilight's body grew as the intruder urged her to move toward the light. While she herself could not make this connection, not doing anything was no longer enough for the torment to stop.

She desperately tried to react, each attempt stopping when the parasite punished her for doing the wrong thing. Eventually, she found that moving closer to her window made it let up. She obeyed until her forehead ended up bumping against the window repeatedly. Another lurch passed through her from her horn, and she had to back away this time.

Now out of the light, the pulsing thing directed her to find a way out. She realized this when it reduced the punishment the moment she left her room. Getting down the stairs took a bit longer, since she first tried all the other places on that floor, and since the parasite thought trying to operate a door was a rebellious act, it took another ten minutes before she finally managed to crawl outside through a window that had been left open.

Bathed in sunlight once more, Twilight Sparkle groaned as the pressure in her head urged her to follow its source, so she lifted her hooves and calmly set off in the direction of the afternoon sun. There was no demanded pace, and she did not intend to hurry without being forced to, which gave the other inhabitants of the town plenty of time to stare at her in shock as she marched past them, a dazed expression on her face, and a bright green, pulsating thing living on her horn.

"Mmm..." Pinkie Pie sniffed at the warm and heavy pot. Licking her lips, she set it down on one of the tables in front of Sugar Cube Corner, her friends gathering around her. "Smells really good, Fluttershy. A new recipe?"

The pegasus blushed. "Just something I threw together. You were all so nice to help me last week. It's the least I can do."

Applejack patted her on the back. "Don't mention it, sugarcube." She frowned. "Say, anypony know where Rarity's hidin'?"

"Coming~!" the mare in question called out. "Sorry I'm late, everypony. There were no clean dishes left, so I didn't have time to get everything else after cleaning a few." She trotted up next to them, horn glowing, and six sparkling clean bowls levitated out of her saddlebag, along with a bundle of spoons and a ladle, which she quickly arranged in front of everypony's seats. She followed up with some colorful napkins and a packet of mints, making her friends stifle a laugh. "What?" She huffed and held her snout high. "I'm not just going to let us eat like animals now, am I?"

"We better wait for Twilight though," Fluttershy said as she took her seat. "Hmm... You know, it's not like her to be late. Maybe she ran into some trouble?"

Rainbow Dash chuckled. "Nah, she's probably just doing checklists about checklists again." She pulled the steaming pot closer and reached for the ladle. "So what say we—"

A series of gasps and panicked cries from around them cut her off. They quickly turned to look, jaws dropping when they realized what the commotion was about.

Twilight Sparkle did, in fact, make it to their appointment. She was almost on time, too. However, the parasite currently living in her head made sure she was in no condition to partake in a mid-afternoon supper with her friends, late or not.

Everypony around stared in horror at the grotesque image, a few of them murmuring and stumbling out of the way as the unicorn marched down the street toward them, only to walk straight past, oblivious. Within moments, she was just a few paces away from the table where her friends sat.

"T-Twilight?" Pinkie Pie whimpered. Her legs shook as she got off her seat and stepped up to her friend. "Are... Are you okay?"

The mare did not seem to notice her at all. She kept on marching, an empty look in her eyes, face contorted and stained by tears, jaw hanging open and drooling. Occasionally, the thing in her horn would move a little faster, and she let out a small, guttural moan.

Rainbow Dash floated several feet off the ground, keeping pace with the catatonic pony, but not wanting to come any closer. "What... What the heck is that thing?" She pointed at the pulsating creature in disgust.

"Celestia have mercy on us..." Applejack whispered. She ran up beside Pinkie, Rarity in tow, and waved her hoof in front of the purple unicorn's face. "Twilight! Are ya all right? Can ya hear us?"

They formed a rough semi-circle in front of her, walking backwards while Twilight marched on, not reacting at all to their presence beyond a few more groans and the occasional blink. At one point, they tried to stop and block her path, upon which their friend stopped as well. Their panic grew as she gave a low, agonizing moan, her body shuddering in an odd way as she stepped closer and tried to find a way past them, the thick green mockery on her skull now inches away from their faces.

Fluttershy was the last to catch up. She was the only one among them who remained calm, though she was no less disturbed by the scene. "This..." she muttered. "No... No, that's impossible..."

"What?" Applejack turned to her. "What is it?"

"N-no..." Fluttershy trembled. "No, there's no way..."

"Fluttershy!" Applejack ran up to her and grabbed her shoulders. "Snap out of it! What are ya blatherin' about? Do ya know anythin' about this?"

"Yes. It's..." The pegasus bit her lip. "It's a parasite. But..."

"But what?" Rainbow Dash joined in. The others approached as well, while Twilight inexplicably remained still right where they left her.

"It infects snails."

"Parasite? Snails?" Pinkie said. "What are you talking about?"

"Snails. There's a creature that does this to them. It looks exactly like... that..." She pointed to the thing in Twilight's horn. "...except smaller." Her outstretched forehoof shook. "And that's what I don't get. How... how could it infect her?"

Rarity blinked. "Fluttershy," she said. "Listen to me. This... this parasite..." The word itself almost made her gag. "What does it do exactly? To the snails, I mean."

Fluttershy took a deep breath. "It crawls into their tentacles and... controls them. It lives in their stomachs and... sends its limbs up from there... to take over." She looked at Twilight again and gulped. "In her case, I... I think it adapted to go for her horn and... it must have gone through her brain along the way..."

Rainbow Dash felt her jaw drop. "Y-you... you mean... It's in her belly and... It went into her...?"

Fluttershy nodded. "Yes."

All the ponies turned back to their catatonic friend, a deathly silence coming over the scene, only to be cut off by another gurgle from Twilight as she slowly resumed her march.

Applejack and Rainbow Dash both screamed at the same moment. Pinkie Pie summoned a bucket out of nowhere and emptied her stomach into it. Rarity just stared blankly, not saying a word. She continued to do so for several seconds before collapsing like a rag doll, eyes rolling back as she lost consciousness.

Author's Note

Don't ask why this exists. Just focus on what's in it.

I may decide to keep writing this based on the feedback. Leaving it "incomplete" for now.

Also: the latest EQD contest is a load of horseshit. You can consider this my unofficial entry to it.