"Big sister...! I'm ready!"
"Are you? Are you sure you want your power back? You're so cute as an un-powered princess pony."
"Don't joke, sister! I can help you again! I can lower the moon, set the stars, all of that like I used to do. Just let me have my power back."
"Alright... But I can't give it to you."
"Why not?"
"I don't have your power. I naturally can set the moon and set the stars without your power. Not as well as you, but all the same. No, when your power was sealed away for safe keeping, I put it somewhere nopony else would ever seek it."
"Where? No matter where it is, I'll go get it!"
"I know you will... Go to the garden, to the statue of Discord. There, you will say a passage of words. Once you do, you'll know the rest of the way from there."
"What're the words?"
Princess Luna looked to the petrified form of the once great chaos demon, her small frame being vastly shadowed by the colossal statue and pedestal. For a rare occasion, the garden of the royal castle had been vacated by order of Celestia so that Luna could progress with her mission without curious onlookers. The young princess moved the note she had been holding in the clutch of her dim magic, making out the passage Celestia had left for her to 'lead her way'. Slowly, each word flowed naturally from her young lips: "Harmonic, corruption, nomadic, indignation. Light and dark, eclipse the dawn and bring to dusk."
A moment after her final word, the stone slab under Discord's statue began to rumble an off-putting shift. Slowly, the grey slab started to move off to the side, letting forth a shimmering light from the ground beneath it as if magic was creating a pathway as the stone moved away. Luna watched calmly but curiously as the stone moved to reveal the shimmering pass. Once the shimmering died down along with the movement of the stone, it revealed a passage of stone stairs that led into an abysmal darkness. "You'll know the rest of the way from there." Celestia's words rang true as Luna descended into the darkness that the statue once covered.
Even in her weakened, smaller filly size, Luna's hoof falls made for loud echoes into the surprisingly dry and dust free passage. The faint light of the morning outside aided her in seeing the steps ahead of her one after the other, echoing off another clack as she stepped to the next. After a while, the faint light from the outside began to be just that: faint; disappearing and fading away to only dull hues touching against carved stone. Luna forced her eyes to strain ahead, making her steps more cautiously as much as slower. The deeper the passage went, the more her curiosity was remounted to fear. With another step forward, her hoof was not met with the clopping echo of stone, but rather a dull thump as she stepped onto a softer substance.
Finally, even Luna could not stomach this level of darkness and sparked an orb of illumination from her small horn. As the passage was re-lit, the young princess was a bit surprised by her new surroundings. Her hooves had found an ornate carpet decorating the floor of a rather cluttered collection of books, knickknacks, trophies, and the sort lining the walls and corners. Luna's orb moved to the center of the rather small room, allowing her to see the entirety of what was around her. Though the orb gave off a light that hued blue, she could make out what most of the objects and trinkets were. What had really interested her was that not one book had a trace of dust or cobwebs drawn to it like most hidden tombs one would read about in adventure books. Everything in the room smelled fresh, perfectly preserved for however long it had all been down here.
Looking over the collection of item, her sight was captured by a black tome that stood out above all the others. Unlike all of the other books and assorted objects, this one black tome was placed on a lectern at the opposite end of the stairway. When she drew closer, she could make out the symbols lining the face of the book: a few decorative stars...
All at once, Luna felt a lump form in her small throat. Just looking at the book was bringing memories back to her that she would have rather forgotten. Yet, she pressed on and looked at the book further, trying to repress the thoughts that were swelling her mind. The book itself was perhaps filled with brilliance... But that was not what she was interested in. The single symbol on the front struck her as the most interesting. For that symbol, all the trinkets, books, and collections in this small room slowly pieced together the once owner of it all. "Star Swirl..."
As the name left her in a hushed breath, her attention was quickly drawn to a new, slowly growing, source of light. Above the lectern and the tome she stood before was a low-bearing shelf with only one object held on top of it. A hat. A hat that was now glowing dimly with a dusky yellow and blue as it began to drift off of the wooden shelf and down to the lectern and book. Luna staggered away from the sight, losing her concentration and forcing the orb of light she had made to disappear and leave her with only the glowing hat as her source of light. That hat was unmistakable if only for the horrid design of it and the gaudy bells; it was the hat Star Swirl was most known to wear. Slowly, the hat drifted closer to Luna in the center of the room, but stopped between her and the book she was studying. To her growing surprise, the hat began to ring with soft bells sounding as the light from it began to grow more clear and wider in reach. Suddenly, the hat began to hum and Luna's eyes were suddenly locked against the hat. All at once, the world around her disappeared into an endless abyss, leaving her standing in absolute darkness with Star Swirl's hat still floating before her.
Luna watched as the hat started shining a spectacular show of beams of light from the bottom frame of the hat. Spiraling and spinning faster and faster, the lights forced Luna to shut her eyes for but a moment as sound faded away from the world as well. When Luna opened her eyes, she returned her gaze to look at the hat, though saw much more. Fear, hesitation, grief, rage, joy, disbelief; all surges of emotions assaulted Luna's mind and heart as she looked upon the impossible standing before her in this realm of darkness. "...Star Swirl...?"
The being before her wore Star Swirl's hat over his yellow coat and knotted white mane and beard. His head made for a short, even nod before his throat cleared to a grand echo that filled the vast abyss. "To that, I will say yes for simplicity sake. Yet, in truth, the long tale of the grandeur of my posthumous reincarnation would lead to the answer no."
"It's you..." Luna was both relieved and grated in her realization.
"And it is you, Princess Luna. Which I surmise as your sister sending you here for me to grant you the power she gave to me to hold for you for when you were ready and had returned. Celestia, wise as she was, had not planned on me giving a rest to my immortality before you returned... One of many things we were blinded to within those years. Yet, I had prepared this conjuring of myself to remain within my hat to bestow upon you your once great power when you had come to reclaim it. Should that be all, I will grant it upon you now..."
"Hold on a moment, Star Swirl--or whatever you are... Why did my sister give you my powers to hold onto?"
"Celestia had viewed that the only one that your powers rightfully should be sealed upon should have been the one you had---" Star Swirl suddenly fell silent, though he still stood before Luna in their realm of darkness.
"...Had what?"
"Luna... Did you look within the tome that I had placed upon the lectern? If you had not, let me explain what was within it. Within that book is the compendium of all my greatest spells and knowledge. I had spent the greater parts of my life writing within it... However, you will find, should you open it, that the final spell and many of my final thoughts are not finished. Indeed, perhaps only half of the book has writing within it."
"Did... Did you die before you could finish it?"
"No... Because I could not finish it, that led to my death..."
"What do you mean? Why couldn't you finish it?"
Star Swirl went silent once more, but only for a moment. Slowly, his had drew off from atop his head and moved up far enough so Luna could see his face in full. Luna felt sick as her eyes widened with welling tears at the very instant she saw Star Swirl's eyes. "Star Swirl... What--" His hat fell back over his face and he breathed a silencing cough.
"In your submission to the darkness around you, thus creating you into Nightmare Moon, your sister and I had attempted to interrupt you... My own hubris brought this upon me. If I had allowed Celestia to do it alone... But, that is the past... This moment now is what matters."
"N...No... Star Swirl..." Luna could not fight her tears as they fell down her youthful face. Now, looking at Star Swirl, all she could feel was grief, remorse, and loathing for herself. "Star Swirl..."
"Luna, do not weep for me... I am only happy that you are alive and returned to your sister..."
Everything in Luna broke with Star Swirl's soothing, wise voice speaking to her. "Star Swirl...! I... Do not speak to me as a friend... I am not your friend..."
Luna hung her head to the abyss below her, letting her tears stream and plummet into the endless vastness under her. As she sat there, Star Swirl stepped to meet her and gently put his chin against the crux between her horn and left ear, cradling her close. "Weep no longer, my princess... The shadows no longer hold you... You have always been my greatest friend... I love you, Princess Luna."
"But I blinded you!" She shouted into his chest, her tears clustering against the matted beard of Star Swirl as he held her.
"Yes... You did... And because of that, I could not finish my work. So I charge you now, princess... I charge you to carry this grief with you and live for us both... You will be my eyes to the world I could no longer see... And you shall be as you once were..." Luna continued to sob with great tears coming down her wet face as Star Swirl faded away and the light that made him reformed to mold around Luna's body.
Luna's form was consumed with stars and swirls of golden-blue light, threads of it diving into her and making her body shine a bright blinding white. Her legs extended along with her mane springing to a luster of life, flowing out around her. The horn atop her head sized out and sharpened along with her wings feathering a great deal and growing to a magnificent degree. As the light that consumed her faded away, so to did the darkness to bring the room she was once in back to reality. Now, sitting against the carpet in the unlit room, Luna no longer sobbed, yet her eyes remained closed. As if everything had to set in, Luna slowly picked herself up to her familiar long legs and rustled her wings against her tight form. Slowly, her eyes reopened and brought with them a pure white light that lit the entire sanctum as well as the passage behind her in a brilliant light.
"We shan't fail thee, our oldest friend. Rest assured, thy will shall be completed..." Her rejuvenated horn swiped up Star Swirl's black tome as well as the old wizard's hat before she went back up the stairs.
Not only had her power been returned, but so too had her purpose and reasoning... She lived now not only for herself, but for the unicorn that had sacrificed his life's work for one princess.
