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// Prologue 
// Story: Discordant Disaster 
// by LewdaCRITS 
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The Mane 6 wasted no time using their Elements of Harmony to turn Discord back into stone. Discord begged in disbelief to be spared, but by that point, it was too late. He snapped his fingers one final time before his entire body was encased in stone. For the second and final time, Discord was defeated.
In the aftermath of Discord’s brief but impactful reign of chaos, Equestria reveled in the hard-won victory of the Mane 6. The Elements of Harmony had once again triumphed, restoring order and peace to Ponyville. Once the town was returned to normal, everyone went about their usual routines, and it looks like most things were going smoothly.
Princess Luna back to raising the moon was another chore off of Celestia’s plate. Sure, she herself can do it, but was no an easy task. She was using twice the magic to lower the sun and lift the moon at the same time. It can get exhausting, especially after doing it for a millennia. But what hurt her the most was Luna’s banishment and how harsh her punishment was, but she knew it had to be done to keep Equestria safe. Ever since she returned as Nightmare Moon and restored back to her normal self by the Elements of Harmony, while Celestia was willing to forgive her, Luna never forgave herself. In fact, Luna was deeply depressed from self-loathing after all the heinous acts she’s done and how immature she behaved a thousand years ago. It took a whole year of therapeutic help, but Luna was finally ready to fulfill her duties of raising and lowering the moon again and ruling alongside her older sister as a princess. Celestia was more than thankful her younger sister is back and feeling better.
As Luna raised the moon, Celestia got ready for bed. She did remember Luna not feeling very well lately. She’s been staying up past her bedtime on some nights and would be tired all day. Thinking she’s just insomniac, she encouraged her to keep a consistent sleep schedule and avoid stimulants close to her bedtime. She agrees, and as of right now, she’s seeing a bit of improvement. Celestia can rest feeling thankful. She switches off the lamp next to her bed, climbs into her bed, and makes herself comfortable before closing her eyes, preparing to drift off to sleep.
A few minutes pass. Celestia hears slow, faint hoofsteps coming from outside her bedroom. Her door, which hasn’t been closed all the way, slowly swings open, revealing the silhouette of a disheveled Princess Luna. She groans as if her lack of sleep has put her in a zombie-like state. Celestia hears this and her eyes blink open to see her troubled sister on the doorway.
“Luna…?” She got out. “Are you feeling alright?”
Luna’s response came only in the form of more groans, each growing in intensity as she stumbles closer to her. This only serves to worry Celestia and leave her uneasy.
Without warning, Luna lunges forward towards her older sister, mouth gaping wide for a bite. Celestia didn’t have time to react before she found Luna’s teeth digging into her neck. She screamed in agony and shock, her cries of pain echoing throughout the hallways of the castle. She manages to wrestle Luna off of her and shove her away. Luna falls onto the floor. Celestia hastily crawls to the other side of her bed, turning on the lamp to get a better view of her surroundings and her sister. What has happened to her, Celestia wonders. What compelled her to bite her own flesh and blood?
She hears galloping from the hallway, and two unicorn royal guards came in through the door, each with magic at the ready.
“Your highness!” Said one of them. “What’s going on?”
Celestia looks at her sister rise from the ground with a growl. Thanks to the glow of the lamp, she sees that this isn’t Luna anymore. Her eyes are black, only accompanied by white pupils staring down her target. Her eye sockets are also covered in darkness, the color matching her eyes, making it seem like it’s just a shadow cast over her eyes, but now with the light, it is clear that this is no ordinary shadow. Something had taken control of Luna, and Celestia needs to know why.
“Something's wrong with my sister!” Celestia says as Luna jumps over the bed to go for another attack, only for Celestia to dodge her lunge and run straight out of her bedroom, closing the door behind her. She orders them to barricade the door while she finds a paper and pen to write a letter to Twilight. Though she may not be awake right now to receive this message right away, it’s now or never. If she’s gonna die soon, she might as well send word out there that her sister needs saving.
Once she finds a pen and paper, she lifted the pen via her magic, with difficulty, and hastily wrote:

Dear Twilight,
 
It is with utmost urgency that I write to you about an unexpected turn of events that took place in my castle. It involves my sister, Luna. She may have been taken over by some sort of curse. And I urge you to contact a few other magic experts and find a way to lift this curse. Tell them to come by my castle in Canterlot. I'll be waiting. 
 
With hope, 
 
Princess Celestia.

She folds the paper to fit into an envelope with a red and gold royal insignia on the seal flap. She closes it and gives it to another one of the guards, who was galloping by to help the others keep the door shut, as Luna is now trying to break through. This guard happens to be a female pegasus.
“Send this to the Golden Oak Library.” Celestia orders. “You’ll know when you see it.”
“Yes, your highness.” The pegasus complies, taking the letter and galloping out of the castle. Once she was outside, she flies full speed to the Golden Oak Library. The library was almost impossible to miss, since it’s a large tree house, while a great majority of the houses in Ponyville are just regular houses. Finding it should be as easy as pouring one's own cereal.