All was still in Equestria. Sunset had just left its last rays on the land for the day and the luminous moon rose high in the sky. Stars twinkled brightly as one of the only creatures of the night drifted through the sky, Luna.
She twirled and danced through the evening wind, leisurely checking that every pony was sleeping soundly. When she made sure their sleep was sweet she soared high above the clouds, bursting through their cool surface. She laughed gleefully as she soared way up high and dove down, having the wonderful feeling of falling.
Man, I'm so glad that I'm off of the moon after one thousand years, she thought. It was absolutely terrible!
She did admit she sometimes missed the moon and it’s dusty surface. It was always peaceful, having the whole satellite to herself and no one could boss her around.
She let her wings fly out and swooped up before she hit the gravel road. The few years she had been home were absolutely the best years she could have asked for, and could not be topped. Her sister bonded and forgave her, and the elements came over to congratulate her for coming back to her original self and raising the moon daily. The only problem she had was that no pony would stay awake to appreciate her moon. She shrugged it off. More for her, right?
She sighed and gazed up at the stars. They seemed to glisten and shine for her. Luna’s eyes swept over Canterlot. She looked for something to do for the few hours of free time she still had of the night, other than tidying up her room or paying visits to the nocturnal animals. Then she had an idea of something she had not done in a thousand years and suddenly missed deeply. It was perfect.
She knew that her plan would involve pain, loss and sadness but would include love, fun and happiness, so much happiness.
Her bright blue eyes lit up and she zipped home with vigor and prepared for the next night’s adventure. She settled down on the bed of pillows and closed her sleep deprived eyes as the sun peeked over the horizon. She soon fell into a deep sleep, dreaming of who knows what.
Luna slept as Celestia and the other citizens of Canterlot went about their daily chores, and before long, the sun was dipping below the horizon. Celestia woke her sister up and she went about raising the moon with eagerness.
She took to the window and talked to the creatures just outside of the Everfree forest for an hour before she visited her first dreamer of the night; Twilight.
She flew past the many houses of Ponyville and landed soundly on the Crystal palace. She concentrated all of her magic and disappeared into a blue mist. The blue mist flew through the door like a ghost and up the stairs until she reached the alicorn’s bedroom.
The covers were flung against the end of the bed and the princess lay on her back, snoring up a storm. Drool dripped out of one corner of her mouth and her head was at the end of the bed. It was an absolute mess. The princess reappeared from the mist and stood at the end of her bed. She brought her horn down on the princess’ head. Her horn lit up and her eyes glowed with power. Mist flowed out of of them and her smile grew big. Then she disappeared into a blue mist swirling into Twilight’s head.
She smiled. This was definitely going to be good.
Luna appeared as what seemed like a ghost. She looked faded and like she didn't belong in this world. You could walk right through her and you wouldn't even know unless, that is of course, you wanted to see her. Then that is a whole different story.
Twilight woke up surrounded by a huge circle of columns of books that reached to the sky and beyond. She looked down at her hooves and she saw her stuffed animal, Smartypants. She hugged the raggedy doll close and explored the tiny space that she had.
She surfed through the books, not looking for anyone in particular until she found one that was not like the others. It immediately caught her eye, and she plucked it from the column. There was just one problem, it wouldn't budge. Now, in a normal situation she would have just given up or used magic, but remember, we are in a dream. She tried time and time again, but to no avail.
Then something clicked, literally. The sound resonated through the tiny space ominously and she let go and backed away to the other side of the small space.
Clunk
There was a scraping sound as the library closed in on her. Twilight's ears went back and she clutched the doll with a death grip as the walls closed in. She let out a small whimper and started crying. Twilight looked at her hooves again but Smartypants was gone and she was all alone.
Luna drifted through the library walls, realizing what this was.
It was a nightmare.
Tears filled her eyes as she watched the helpless princess tremble in the closing walls of the library. She knew this was all just a dream, she knew that the nightmares don't last long and she knew that when she woke up she will most likely forget the nightmare. But she also knew that nightmares brings out the deepest and darkest fears some pony has. That's how she managed to take over Equestria for that long a thousand years ago, by using their darkest fears against them.
Then she saw Twilight take to the sky and fly up and up and up above the endless columns, hyperventilating and panicking all the while. The walls were closing in, but she could never find the end. She stopped flying because she got stuck. The walls got closer and closer...
Twilight jerked up in her bed with a cold sweat, her heart beating like a drum, and a blue mist quickly leaving the scene to dash out the door. Luna materialized out of the mist and tears were rolling down her cheeks as she galloped down the streets of Ponyville.
She forgot how a nightmare felt. How horrible it is to be in some place where you have no power, like Nightmare Moon. She had no power and watched as she destroyed the things and ones she loved and cared for most. She hated nightmares, absolutely despised them. She had no control, just like Twilight did over her dream.
She soon ascended to the cool midnight sky and scurried home. She dove beneath her pillows, wanting to get away from the world completely and fall into her own little happy world. Which she did indeed do in a couple of minutes. The moon's light shone on the dream walker herself, its calm, blue rays wanting to find out what the pony dreamed of.