"Glacial Chill"

"Okay, so, here's the plan." Twilight Sparkle announced to her friends, who were sitting at their thrones.

Rainbow Dash raised her eyebrow, "What plan?"

"The plan, Rainbow! Have you even been listening to what I've been saying for the past hour?" The Princess of Friendship sighed, watching her friend yawn as she spoke, "I've been skeptical about some ponies lately, especially Trixie." Twilight glanced down at the blue mare curled up in the corner, Starlight's hoof draped over her.

"Ah'm not sure about that, Twi'. Ah mean, just look at 'er. As long as she has Starlight, she's harmless." Applejack said, giving a slight side-smile. Twilight sighed once more.

"But that's just it, Applejack! What if Starlight isn't here?"

"Then she'll just have to deal with it!"

"Just tell us the plan, already!" Rainbow yelled, causing the two to quiet down. Trixie shifted slightly and whimpered, causing Starlight to nuzzle her.

"Alright. So.. Err-" Twilight went silent for a while, looking confused.

"So?"

"Would it be childish to say that I forgot?" The purple mare smiled sheepishly, earning a face-hoof from Applejack. Rainbow Dash snickered.

"Gee, Twilight forgetting something? That's rare!" She laughed.

"Anyway, I invited Tempest over. Maybe she could help keep an eye on things."

"She actually accepted this time?"

"Sure did." Tempest's voice was heard from behind the purple princess, causing her to jump. The mulberry unicorn chuckled at that, "Hey Twilight."

"You can't just scare me like that! ...How'd you even get in?"

"I have my ways."

Twilight rolled her eyes, but smiled either way. The lavender unicorn eventually dropped the topic of 'The Plan' and they all started chatting to one another, quietly as to not wake up the sleeping couple. After moments of laughing and giggling together due to a joke that Pinkie Pie shared with them, the room went pitch black. The yelp of Trixie was heard over the multiple gasps, waking up the pastel pink unicorn next to her.
The room lit up again in a hot pink flash.
The blue mare was upright and shaking in Starlight's embrace, eyes dilated and breath quick.

"What just happened?" Starlight questioned Twilight, who was just as confused as everybody else in the room.

"I'm not sure, but it can't be good."

A few seconds afterwards, Spike burped out a scroll in a green flame.

Dear Twilight Sparkle,

This is an emergency, come to the Canterlot Castle at once.
An old enemy has returned, and she is not happy.

-Princess Celestia

"We need to go!" And with that, Twilight ran off, her friends and Tempest following close behind. Starlight grabbed Trixie in her magic and ran after them. She teleported as soon as she was close enough to Canterlot to reach the castle with a teleportation spell.
Starlight placed down the blue mare, who immediately cuddled up to her once she sat down.

The 9 mares and Spike sprinted into the throne room, skidding to a stop. Trixie cowered at the tense atmosphere of the room, staying close to her mare friend.

"I am very glad you came, all of you." Celestia's voice echoed through the silence of the room, "This is not good. If this enemy finds anypony outdoors, there will be a much bigger chance she could take over Equestria."

Tempest raised an eyebrow, "Two questions, princess."

"Go on?"

"First of all, who is this enemy? Second, if she finds anypony outdoors, then why did you call us here?"

"This enemy is a pony named Glacial Chill." The blue unicorn's eyes dilated once again as she heard that name, "She was an old friend of mine who did not get what she wanted. She created a young soul for it to develop on it's own and follow in her hoof-steps. It eventually transformed into a foal, in which Princess Cadance found and cared for until it was old enough to leave. We banished her, and she is now planning her revenge."

"And my second question?"

"Well, that's easy-- She has not arrived yet. Be careful on the way back, however."

Twilight put her hoof to her chin, lost in thought, "What if we find the 'soul' that Glacial Chill created? Maybe it will know how to help!" She smiled at her own plan. Celestia smiled and looked towards Trixie.

"I believe she is already here."

"Celestia, Why don't you just let me do it?" The pastel blue mare asked the princess.

"You do not understand, my friend. If you do, Equestria will be at risk, and it will be our fault." She furrowed her eyebrows.

"So what if Equestria is at risk? I need to do this, no matter what."

"What will Jack-Pot think of you?"

"Don't bring him into this! This is something for me to deal with, not him!" The mare growled, her eyes darkening for just a moment, "Just let me do this! You can't stop me, princess!"

"I'm afraid you cannot do this, and I'm afraid I can stop you. I'm giving you a chance to change."

"Well I will do this!" Her horn glowed aqua as she shot a magic bullet at her former friend, who defended herself will a golden barrier.

"Very well then." The aura of Celestia's horn glowed brighter as the room was devoured by a white light. When the blinding light died down, the mare was gone. All that was left was a violet wisp.

She was in a dark void.
She was dead.
Wait, was she?
Who is she?
She is going to be revealed later.

She is not normal.
She is an error.

Broken.
Dying
Dark.

"Wake up."

"Wake up."

"You have to wake up."

"Wh-Wha?"

"Welcome back to consciousness."

"What happened?" The mare growled and rubbed the spot under her horn, then perked up, "Shoot! The plan!"

"The plan is useless now, my little pony."

"Stop being so formal with me! What's going on?! Who are you? What are you?"

"I am a spirit. Perhaps a figure of imagination." A dark chuckle could be heard, "I can be whatever you want me to be."

"What?"

"In other words, I am nothing. I am the dark, lingering in shadows."

"Yeah, nothing you just said made sense." The blue mare raised an eyebrow.

"Maybe to you it didn't. However, I did not bring you here just to have a friendly chat. I have an offer. Or, perhaps, it is an offer for the future."

"...How far into the future?"

The darkness chuckled, "Ten years. Maybe more, maybe less."

"Whatever, what is your offer?" She groaned at the thought of the long wait, "I just want to get this over with."

"In a few years time, I will free you. On one condition." A jagged red smile with beady eyes faded into sight in front of her, "You take me with you, and we will take over Equestria with the darkness that it deserves."

The silence went on for what felt like hours, though it was only a few seconds, before The unicorn finally made her choice.

"It's a deal, sir." She held out her hoof, hoping for at least something to shake it. Her wish came true as a black claw shook it in agreement.

"Good choice, Glacial Chill." The jagged smile widened as it spoke once more,

"As the darkness spreads, we will be the new rulers of Equestria."

Author's Note

This is my first published story on Fimfiction, so it may be bad.
Please just go along with the story line, I'm just writing my thoughts at this point.

OH! Also, sorry it's so short!
Also I would add a picture of Glacial Chill but it won't let me.