The castle of the royal sisters was abandoned for a thousand years. Stone walls rose above the forest with the determination to resist the passage of time and erosion. Magic interwoven in its construction resisted the natural forces fighting to return the massive structure to rubble. Over a thousand years the magic has been fading. Moss was growing in damp corners, rainwater found it’s way into the foundation, small rodents and insects hide in cracks and rubble. The magic was losing and time keeps passing on. The thousand year battle had no witnesses, no sound of civilization, no sapient life was there to see the structure resist nature’s might.

Until today, a thousand years since the fight between the two royal sisters. A millennium has passed and the Princess of the night, Nightmare Moon, has returned from her imprisonment on the moon. In the once-grand throne room, she stood a tall and proud horse like body sleek and toned like a racing horse. Her coat a deep blue-black shade many would call it just black, her mane and tail a blue that sparkles with thousands of stars like the night sky blowing behind her like a cloud. Her wings flap showing sign of the frustration she felt.

The source of the frustration stands before her. A purple unicorn, lavender, no a magenta Nightmare told herself. This magenta unicorn was the only one stopping her from her rightful ruling of Equestria. ~Twilight Spackle? No that’s not right what was her name? Oh, she was still talking, what!~

Nightmare Moon watched as shards of the stones she just shattered rose up and start floating around the other five ponies. On each magical gems appeared as necklaces. The Elements of Harmony the only things that stopped her a thousand years ago, items she destroyed. Still, there are only five, she still did not have the six elements.

“You still don’t have the six element, the spark didn’t work!” Nightmare Moon stated as she stamped her hoof against the stone floor. “But it did, a different kind of spark...” Oh no more talking, really did she get a cutie mark in lecturing? Nightmare Moon stopped listening at that moment. She needed to stop this! Magic started building up in her horn one good blast of magic and the magenta unicorn will be nothing but a burn mark. ~NO! I won’t let you Nightmare Moon!~ The voice in her mind shattered her focus. Deep inside the mind of Nightmare Moon, the once good Princess Luna still struggled against her alter ego. The two personalities fought against each other. Luna once used those very same elements against a Spirit of Chaos, Loyalty, Kindness, and Honesty was twisted into a dark echo. Nightmare Moon Cruelty, Deceitful, and Selfish she fought to stamp out her once good nature. Then the world will be hers and the night will last forever.

Once more she struggled to form the spell in her mind and again the will of Luna fought to keep any spell forming. “... The element of MAGIC!” “NOOO" Nightmare screamed as any thought of fighting back ended as all six ponies lifted up in the air and a blast of rainbow magic struck her. There was no pain Nightmare thought it would be painful as the magical rainbow engulfed her. In the sphere of magic, the influence of the Nightmare was stripped away from Luna. Thoughts fragmented as the two personalities were pulled apart like two fighting children separated by a parent. The will of the Elements the tree of Harmony, the parent in this case. The power that was stored for a thousand years went to work. Saving the Princesses of the Night both of them. A bit of Luna’s soul removed and remade for the seed of life, it was then bound to the mind of Nightmare Moon. Flesh made by a drop of Luna’s blood as a base. The Elements of Harmony are not weapons, they don’t destroy. In this case, they gave life.

The six ponies that braved the danger-filled forest of the Everfree, who faced the personification of nightmares rose off the floor each feeling drained by the event. The sky outside lit up as the sunrise lit up the once dark throne room. A figure seeming to manifest from the light of the sun itself took shape. A white Alicorn majestic in form and grace, built more like a workhorse then her dark counterpart Celestia Princess of the sun walked the halls of the old castle once again.

Celestia overjoyed her student Twilight Sparkle saved the world, the trust and hope she put on the young unicorn did fill her with worry. That no longer the case as the threat of Nightmare Moon was over, and more. The once good Princess Luna her long-lost royal sister was back alive. The fear of rejection fought the hope the thousand years of loneliness was finally over, she went to the now blue alicorn. With tears, she leaned down and nuzzled her younger sister. Things will finally get back to normal.

A scream of fear and anger filled the throne room. “WHAAAAAAAAAAAAAAA!” Celestia blinked as the cry of a foal was heard behind her sister. Luna jumped up and turned to see a small foal backing up till her flank hit a wall. Her body royal purple her mane and tail a dark purple so dark it was almost black. The teal eyes looking around in terror at the two larger alicorns.

A soft gasp “a foal oh my...” Fluttershy said as she got down moving so slow she was barely moving at all. “...Don’t be afraid we won’t hurt you little one.” The aura of kindness made the pegasus almost glow. Nightmare Moon blinked at the large pegasus. Though she didn’t look like her older and far larger self it was indeed Nightmare Moon in the body of a little foal. She shook her head trying to come to grips with what she was seeing.

“How could this be! I’m here how could I be looking at myself?” The filly said in clear baby talk. It sounded nothing like the language the others were using. Mostly just goos and baws. She looked at Luna then at the super-sized Celestia.

“How could there be an Alicorn foal here?” Twilight Sparkle the very unicorn who defeated her now had the Element of Magic as a crown on her head. Nightmare noted the slight twitch to Twilight’s eye as she spoke as a bit of her mane spang out of place.

“The poor dear just look at her. Her mane and tail look like they never been brushed.” Rarity the other unicorn brushed her hoof through her own indigo mane, stated as she looked at the frightened Nightmare. “Thought the color is just a wonderful shade.”

“Really we are in an abandoned castle and you focused on my mane?” Nightmare babbled as she got to thinking.

Twilight was now in full study mode looking as she looked at the filly. “I have a theory. Could ... sorry, Princess Luna, but... could Nightmare have mated before being sent to the moon...” She blushed beet red. “If there were a chance the fertilized egg was still viable when the elements magic hit. The Elements could have saved the offspring?” She blurts out, looking a little doubtful.

~They did this to me. They cursed me with those blasted Elements! I have to get away end this curse and have my revenge.~ The filly thought to her self as she was looking around for an escape. The Pink one laughed looking down at the foal.

She needed to get away before they attack her again. Looking about she rose to her small hooves and bolted for the door. Only to be snagged by the orange mare with a cowboy hat. “Whoo, they're partner. You’ll be no bigger than a minnow in a fishin' pond.”

Nightmare struggles in Applejack hooves. The fight was hopeless after help raise her little sister Applejack had plenty of hoof on experience in handling a filly with a lot of energy.

Pinkie Pie tilted her head seems to be listening to something that wasn’t there. Then in a babbling baby talk language “You are a baby and look they can’t understand a word you say. Calm down and play weak and helpless I don’t think they even know who you are. Black Snooty, though I guess I have to call you Purple Snooty now.” Pinkie Pie says as she got all the others to look at her. Even Nightmare looked on in bewilderment. Pinkie seemed to not even noticed the looks as she rubbed her chin.

“GASP That means it's her Birthday! Oh, I so got a lot of work to do in Ponyville! A welcome back party for Princess Luna, The Celebration of beating Black Snooty, saving the day literally, and now a Birthday Party!” She was vibrating with excitement.

Nightmare Moon looking at Pinky Pie with both confusion and complete terror. Somehow she knew what was really going on and seemed to grasp what was in her mind. At the same time seems completely absent of any logical thought. Still playing the weak and helpless foal right now might be the best move. She had no magic, and her body was indeed a foal’s.

“This changes things...” Celestia said with just a hint worry. Celestia turned her head to look at Luna. Who shifted her hooves nervously beside her sister? “It seems sister we have much more then I realized to talk about.”

“Tia I... I don’t knoweth whither the foal cameth from.” Luna said looking at Nightmare with sad puzzling eyes. The foal was now laying down following the advice of Pinky Pie.

Pinkie Pie looked to Luna “When a Daddy Pony and a Mommy Pony Love each other very much...”

“Darling I don’t think that’s what she meant. When... well we defeated Nightmare Moon there weren’t any other ponies about. At least I didn’t notice any traces of foals.” Rarity said.

“I... don’t knoweth. Thither so much I can’t recall from yond time” Luna said looking down with sadness and shame. ~Of course we weren’t pregnant at the time. Like I would submit myself to being mounted.~ The little filly snorted and looked away insulted by Twilight’s theory.

“Well, for now, there are more important matters. We need to get out of the Everfree it’s dangerous for a full grown pony, for a foal to be here, the danger is too great. The question of parentage can be determined later.”

“I’m sorry... “ Celestia stopped as she tried to recall if she heard the Pink mare’s name. “But there will be no party. The care of the foal and my sister is paramount. Not to mention the mess I have to handle explaining why the sun didn’t rise when it should have.” Celestia said as Nightmare Moon was lifted up in a golden aura and placed on her back.

“But... Birthday party.” Pinky said her lower lip quivering.

Rainbow Dash came up to the Pink mare and draped a wing over her back “Think of it this way Pinkie. When she is healthy she is able to play your party games.”

Twilight looks over "Besides the first birthday is when the foal is one year old. So you got a year to plan for her birthday."

“Oh okay, this gives ponies the chance to get presents! Can’t have birthday parties without birthday gifts.”

Celestia lowered her snout to Applejack “Is she always like that?”

“Fraid so Princess” Applejack nodded “Fun as can be, her parties are the pride of Ponyville. She’s just a few apples short of a bushel.”

Celestia nodded and headed down the hall. Luna followed along seeming sad but also thoughtful as she took glances at the foal on Celestia’s back. Softly to herself “Couldst. couldst the foal beest his?” A shake of her head as she tried to clear up her mind.

Once outside the thoughts that haunted Luna got brushed aside as she saw the Everfree Forest that surround the abandoned castle. “What hast hath happened here, sister? Where’s the city yond hath used to beest 'round our castle?”

“I fear Luna telling you would cause more harm, but I can’t hide the truth. The magic that was unleashed during the final fight before you were banished to the moon was... devastating. Everything that was touched by the spell that turned you to Nightmare Moon was changed.”

“How much?” There was dread in Luna’s voice a deep fear and guilt she could not hide.

It was Twilight Sparkle who answered. “The Everfree Forest spans 36,000 square miles give or take for growth or trimming back.”

“It was smaller a thousand years ago Luna. That said the area that now known as the Everfree is that large.” Celestia said as they walked her horn glowing driving away any threat.

“Did... did anypony...” Luna softly spoke before Celestria’s wing fell on her withers.

“My dear Luna. It was a long time ago and I know it wasn’t your fault. Don’t blame yourself for what you couldn’t control.”

“I shouldst has't did control it!” ~Not like you could control me. You were begging me to take over at the end.~ Nightmare huffed shifting on Celestia back.

“And I should have seen that you were suffering. Luna, we are both too old to let should have or would have fog our thoughts. I made the Everfree a national wildlife preserve. There are many rare and even valuable life in these woods now that would have died out or never exists.”

Celestia gasped and looked back. Seeing the filly on her back and a line of yellow liquid streaming down. “Seems I will need a shower when we get to Canterlot. I do believe this is the first time I ever been peed on.”

Nightmare Filly smirked and settled down falling asleep. Weak and pathetic she might be but she will grow stronger. A hundred years is nothing given she waited for a thousand already. After all, a foal can cause a lot of mayhem. Dreams of her future plots filled her head as the ponies traveled through the Everfree.

Author's Notes:

I went and rewrote this chapter. Added a bit more detail here and there, clean up the past tense issues. I also noticed a few missed led plot points I dropped. So hopefully this chapter is now easier to read. A big benefit is increasing the number of words!
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Here another story idea of mine. It started with a question. If Nightmare Moon was something that corrupted Luna, then what is Nightmare Moon's real personality? What would Nightmare Moon's goals be if Luna wasn't part of her? So I will be exploring that idea as now Filly Nightmare Moon is a separate entity of Luna. Others had similar ideas the Moonie shorts [Filly Nightmare Moon] by Eighth for example. The problem I have with those is the Second Person perspective. There, of course, Nyx of Past Sins by Pen Stroke.

I have learning disabilities, Dyslexia and Aspergers Syndrome are just two. I know my Spelling and Grammar are bad. I don't have any prereaders, or editors to double check my work. So if you see something please send me a Private message with the corrections and I be happy to fix it. Or post a comment below pointing out the errors. Just saying I have a problem won't help me see where the problem located!