Contrary to popular belief, Princesses Luna and Celestia are not in fact immortal. They were once foals just like any other. While no known records of their youths remain, one can still find the occasional reference to a 'Queen Luminae” which may or may not indicate that there was a hierarchy before recorded history of which our beloved Princesses were once a part. From what I have gathered by research, and by simply asking Their Highness', I have learned that Queen Luminae was in fact the mother of both our sovereigns. The question yet remains, however. What was their foalhood like?
Twilight just finished reading the notes. This was world shaking. To the general populace it was thought that Luna and Celestia simply had always existed. No one questioned it because no one thought of it. This information that she had found in the Canterlot archives was quite trustworthy. They were the notes of Starswirl the Bearded himself. It appears that he had been planning on writing a new book before his death. 'A Biography of the Royal Sisters' the title on the notes dubbed it. She had to ask the Princesses about this. Immediately. She had to know, knowledge was the one thing that she couldn't resist. I'll go and ask them right now! After all, the Princess said that she would be free this afternoon.
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“Princess!” said Twilight as she saw her mentor. She had only been looking for about fifteen minutes before she had been directed to the Canterlot gardens.
“Hello Twilight. Taking a break from all that studying?” said Celestia, a laugh underlying her words.
“Uh, actually Princess, I found some information and I wanted to ask you about it.” responded Twilight.
“Oh? Let's see what it is you've found then.” said the Princess. Before Twilight could show her the notes however, a roaring sound began. They looked up for the source of the disturbance, and saw a swirling vortex of storm clouds.
“I-is that normal...” asked Twilight though she already knew the answer.
“No.” said Celestia, looking both curious and defensive. Ready to fight to protect her subjects. This vortex was unnatural. Whatever had created it may be hostile. As Twilight and the Princess watched a ball of fire fell from the center of the vortex. As it approached the ball split and, now being within range of sight, the two beheld a frightening and surprising thing. The balls of fire were creatures. One that had existed only in legends and mare's tales. A human landed, forming a crater on impact. The second creature, landing a few moments later was equally as shocking, but infinitely more horrifying. That which had followed the human into the crater could only be described as a 'horror inconceivable to the minds of mortal beings'. The mind attempted to give an understandable form to the creature, resulting in what appeared to be the grotesque spawn of a giant fly and an octopus. The mere sight of the monstrosity froze both the ponies in place. The human however, rose and confronted the creature, not even flinching at it's appearance.
The two beings grappled, never leaving the crater. The fight seemed to last for hours, but was in reality only about twenty minutes. Finally the human gained the upper hand, pinning the horror with one foot and grasping the deformed bulk of it's head. The human pulled, and twisted, until with a sound like glass tearing the beast's head came off... and it dissipated into a cloud of black dust. The human stood, staring at where the creature had been, and then collapsed onto the ground of the crater.
It had been a day since the strange creatures had fallen from the sky. Everypony in Canterlot had been talking about the event, especially the horrible fly-octopus creature. Princess Celestia, however, was more concerned with the strange creature that had been unconscious in the private medical wing of Canterlot Castle. A human, a creature of legends so old that even Celestia herself only just remembered them. An outlandish race, capable of doing great and terrible things. She should be afraid, furious even, but strangely enough the creature stirred up curiosity and... a feeling of familiarity.
Almost as though she had seen the strange being before. But that was impossible, humans lived for a bit over one hundred years at the absolute most. She was over two thousand. As the Princess of the Day sat pondering in her throne room, a guard walked in.
“Princess? I have a message from one of the doctors.” said the guard.
“Oh? Has the creature woke up?” she asked.
“Yes, Princess Celestia... and it asked to see you.” said the guard, becoming nervous now.
“It can speak? And it knows my name?” she asked in slight disbelief.
“Well, it can speak, but it asked to see the ruler of the castle. It didn't ask by name.” said the guard.
“Ah, very well. Please find Princess Luna for me and tell her to come to the medical wing immediately.” asked the princess.
“Of course your Highness.” responded the guard, loyal as always.
Hmm. How is it that a human, a creature not seen in Equestria since before even my time, can speak Equestrian? Perhaps if it remains docile I'll be able to ask it. Humans were dangerous, violent, creatures. That much the stories had been quite clear on. Still thinking, she did not notice she had arrived at the room the human was in until her sister and Twilight Sparkle arrived.
“Hello sister.” said Luna.
“Hello Princess.” said Twilight.
“Oh, I apologize I was thinking. Hello to you both.” said the Princess of the Day, smiling a bit at her sister and most faithful student.
“Shall we enter?” asked her sister.
“Yes I believe we should. But be careful, humans are supposed to be dangerous.” cautioned Celestia. They entered the room. The human was sitting up in bed, the jacket it had been wearing hanging nearby, having been replaced by the bandages now around it's chest. It still wore the wide-brimmed fedora that had not left it's head since the fight.
The human turned and looked at them, looking confused for a moment upon seeing the Princesses, before it grinned broadly.
“Tia? Lu-Lu? Is that really you!? My you've gotten big since I last saw you!” said the now beaming human.
“What do you mean the last time you saw us? And how dare you address us in such a way!” said Luna.
“So you really don't remember me? Well I guess it has been over two thousand years. Two thousand-three hundred-and sixty-seven years to be exact. Plus you only ever saw me like this half a dozen times.” said the human, pushing away the tip of a guard's spear. They had readied themselves to impale the insolent human after he had addressed their Princesses in such a manner.
Celestia began to half-remember something. Something that had happened long ago.
“What is your name?” she asked, convinced that it would set her memories right.
“It's me! Ashen Grey, your old foalsitter!” said the still beaming human.
“Ashen... that's impossible, he was most definitely not a human.” Said Celestia.
“Would you like me to prove it? Ask me something only Ashen Grey would know.” said the human confidently.
“What are the three thing Ashen Grey said before he left?” asked Celestia, believing that this human could not possibly know.
“First I granted you and Luna dominion over the Day and Night skies.” answered the human. The shock in Celestia's eyes told that that was correct.
“Next I gave you each a gift. A small cake for you Celestia. Strawberry chocolate to be exact. And to Luna I gave a pouch of of candies.” this time Luna too looked shocked.
“Last, I told you both that the Day was as important as the Night, and the Night as necessary as the Day. One had to exist for the other to be. A gear in the machine of life.”
concluded the human. At this point both the Princesses were completely dumbstruck. The human had gotten each question perfect. There was no doubt, this was Ashen Grey, their old foalsitter, that they had loved like a big brother. Before anypony could react both the Princesses were hugging the human.
“Oh, Ashen it is you!” said Celestia, beginning to cry.
“You're finally back Old Dust!” said Luna, using their old nickname for him, also through tears.
“Tia, Lu-Lu, need air!” said Ashen, beginning to turn blue.
“Oh, sorry!”said Celestia, smiling through the tears, as she and Luna backed away.
“Well, it's good to see you two can still pull off one serious death hug!” said Ashen as he smiled at them.
“Uh, if I may, but what exactly is going on here?” asked Twilight, obviously having been lost in the emotional torrent that had occurred in the space of a few minutes.
“Oh, this is Ashen Grey, our old foalsitter,” said Celestia, now beginning to compose herself. “Ashen this is-”
“Twilight Sparkle.” Interrupted Ashen.
“How do you know that? And more importantly, why do you look like a human?” asked Luna.
“Well what kind of god would I be if I couldn't shape-shift and know somepony's name before having been introduced?” he asked, raising an eyebrow at them.
“Wait. Did you say you're a... a god?” asked Twilight, starting to become frightened. Had she insulted him? Had she done something wrong? Would he vaporize her?
“Well technically yes, i'm a god. But I'm retired, hence why I'm back here in Equestria. I finished up the business I left to take care of over two thousand years ago, passed my responsibilities and some of my powers onto the other gods, and came here. That damn Deep One showed up mid-transit and caught me off guard though.”
he said.
“Um, if I may, what were you the god of?” inquired Twilight, now curious.
“I was the god of Magic and Arcane Knowledge.” he answered.
“REALLY!?” shrieked Twilight. She was good at magic, but he was a god of magic, there was so much that he might be able to teach her she had to ask, she had to know, she-
“Before you ask, yes I'll teach you a bit of what I know. But not all of it. That would cause your head to implode, and nopony wants that.” he said.
“Oh thankyouthankyouthankyou!” yelled Twilight, now jumping around like a filly, feeling incredibly happy. She would be learning from a god now! This was great! The prospect of him being a divine being had slipped her mind.
“Well not today. After a fight like that, even I need a bit of time to sleep. Plus I need to catch up with Tia and Lu-Lu here.” he said, smiling as he called them by their nicknames.
“Please stop calling us that.” said Luna, hanging her head in embarrassment.
“I can call you whatever I want, because I'm still your elder, and the closest thing you have to a big brother. You're stuck with me.” he said, smiling even broader.