One thousand years is a long, long time to wait for revenge. One thousand years that were meant to be a reflective experience, meant to settle down the jealous that had entered her heart and show her the folly of what she was intending to do. None of that happened. She didn't go through some heartfelt journey throughout her banishment. No, that didn't happen until she grew bored of devising ways she would get back at the one who had banished her, who had abandoned her when she needed it. She eventually did go through a soul searching, but that had ended when she found out there was a way to escape, a way to get back to Equestria and to reclaim her throne that was taken from her.
Four entities had come to her; had told her that her time to return was soon. All it took was time, and she had plenty of that. They came to her occasionally, these four entities, and told her what she needed to do; how she needed to prepare herself. They never showed themselves to her, only speaking to her mind, softly, comfortingly. They told her they were stars, and that they had a particular interest in her. She wasn't sure how much she could trust these four, but what choice did she have? The only thing that kept her going was the thought of being able to return, and to take revenge upon the sister that sent her to the cold confines of the moon.
These four knew entirely of her intentions. However, they did not try to dissuade her from this path, but encouraged it almost. And so, she prepared, passing time until she could make it out of her prison. All the while the world below her changed. She did not take notice of the changes; they were of little consequence to her plans. When she returned, she would take the throne, and she would make the ponies-- and all the other species on the planet-- bow to her.
The timing couldn't have been more perfect for her. When she felt she could prepare no more, when she felt the edges of her mind begin to fray from the tedium, the voices returned. They told her that the time had come for her to return to Equestria. They warned her, however, that the world was not as she remembered it, that a great change had taken place and there was much chaos in the world. Typical, she thought. The four entities had told her proof that her sister was unfit to rule, just as she had thought one thousand years ago. But what did it matter what changes had occurred in her absence? She would still return to take her throne, no matter how different the world was. Even as they warned her that things were far different, she disregarded it. If they weren't going to tell her what had changed, she didn't need to concern herself with it. Her time was at hoof, and she would liberate the throne from her sister who was so obviously had failed to lead her country.
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Ponyville was a peaceful town before Celestia’s Spell. And after the Spell it held on longer than any town had the right to, despite its proximity to the spot in which Celestia had chosen to cast her world ending spell, Canterlot. But even Ponyville succumbed to the wasteland that had been created. Frequent raiding from lawless ponies and gryphons and despair had been poisonous to the inhabitants. Those that weren’t killed, left their home to its fate. And soon, Ponyville too became but a crumbling memory. Nopony wanted to reclaim the old thatched roof village. For decades, Ponyville was only inhabited by ghosts from before The Spell, known by locals as a place only fools traveled to, that no one with any sense would try to scavenge from.
In the gutted remains of the local police station, six ponies who were not locals, had made their home. They had chosen the police station for its thick walls, and also because it was one of the few remaining buildings that was still standing. To the six, it was the perfect place to carry out the orders they were given.
The leader of the group, a white stallion with a two tone blue mane and clad in a heavy set of hardened steel powered frame, was sitting in the former chief's office. The office was the more intact part of the building, the windows weren’t shattered, no holes filled the walls, and the paint on them wasn’t peeling too badly. Even the filing cabinets were mostly standing. On the desk in front of him he had a large stack of papers that he was going through. His small team had mapped out a portion of the town, and had a detailed report of each building and street in a three block radius. He was lost in thought when he heard a knock on the door.
"Who is it?" the stallion asked, not looking up from the paper stack.
"Scribe Sparkle," came the answer from the other side of the door. "Sir, I have something you need to look at."
At the name, the stallion flicked his horn and opened the door, revealing a lavender unicorn wearing a thick red sweater with a heavy black vest sporting several pockets over it. "Sit down and show me what you have."
Scribe Sparkle trot forward and pulled the decaying, but still sturdy chair up to the desk and sat down. "Paladin Armor, I came across something while I was digging through the remains of a library five days ago."
"And why are you bringing this to me now, instead of five days ago?" Paladin Armor questioned.
Sparkle pulled a brown bound book and set it down on the desk. "I wanted to make sure it was worth sharing before I said anything," The paladin motioned for his scribe to continue and Sparkle opened the book she brought. "Read this please."
Paladin Armor pulled the book towards him with his magic and read what Scribe Sparkle had marked. "An old legend? That's what you wanted me to see?"
"The terrible mare it talks about is Celestia's sister. The one she banished a thousand years ago," Sparkle informed. "And if that legend is true, then she will return. If she returns, and if she brings about eternal night like it says she will, then Equestria will have another cataclysm. But this time it won't recover."
The armored stallion put the book down and regarded Scribe Sparkle carefully. "And do you know where this Terrible Mare will return?"
The studious mare pulled out a torn map fragment from one of her many pockets, "Right here." She levitated it to Paladin Armor, showing him.
"Isn't that in the Everfree Forest?" he asked, incredulously.
"On the far side."
Paladin Armor sighed, rubbing his forehead with a hoof. "The most dangerous place this side of Canterlot, and you want us to go tromping through it."
"Yes," was Scribe Sparkle's response.
The Paladin looked up to his Scribe. "Alright fine. When is Celestia's fated sister destined to return?"
Scribe Sparkle sat up straighter. "Tomorrow."
Paladin Armor's face met the desk. "Why do I listen to you?"
"Besides me being your sister? Because I've yet to be wrong. I wouldn't have come to you with this if my research wasn't sound," Scribe Sparkle retorted.
He lifted his head up and rubbed his nose, "Ready the others. Ask for a volunteer to stay and hold the Station while we're away. And pray that you're right on this one."
Scribe Sparkle beamed as she rose from her chair. "Oh I know I am. But let's get there as fast as we can."
After Scribe Sparkle left the office, Paladin Armor looked down at the book that was left and pulled it close. "I pray that this is only a fairy tale."