Luna's face was contorted into a frown. Looking around, there was nothing out of the ordinary to distinguish the cave from any other cave. The gray stone walls looked weathered and rough, despite the protection they should have been offered. Beyond the reach of the sun, the cave was dark, and a coolness drifted through the air from further inside the cave. "Are you sure this is the place, sister?" Luna asked. She gradually pulled her gaze away from the darkness to look at Princess Celestia.
Princess Celestia's brow was creased, and her lips were pulled slightly down. She nodded once as she studied what was visible of the cave. "This is the place," she affirmed.
"I do not sense anything amiss," Luna said calmly.
"There is something here," Celestia replied. "It is faint, but it is here..." she trailed off and squinted, trying to pierce the veil of darkness with her sight. It was to no avail. The darkness was thick, almost oily, covering and hiding what laid beyond. After a few seconds, she lit her horn and shined her aura into the cave.
Where the light of her horn struck, the darkness was banished and the cave was illuminated. It was vast, going further into the mountain, then expanding into an immense cavern. Tons of stone and rock had been displaced, but that wasn't what drew her attention. Beyond the weathered cave walls, inside the cavern, the walls looked smooth and almost metallic, vastly different from the erosion plaguing the mouth of the cave.
Luna pursed her lips at the sigh and lit her horn alongside her sister's, adding a little more light to the mix. The walls of the cavern were the same cold, rocky gray as the cave, but they seemed to reflect the light of their magic ever so slightly, causing the cavern to almost have a low, ambient glow.
"This was not like this before," Celestia acknowledged.
"An earthquake would not explain this formation," Luna noted. "Perhaps I simply do not sense it," she commented. She glanced back towards Canterlot. The city stood like a jewel set atop the Canter mountain, almost glistening in the late afternoon sunlight. "It is strange, however. If this was made recently and not by natural means, then we should have detected it, considering the proximity to Canterlot."
Celestia slowly nodded her head up and down. "Prior to yesterday, the last time there was a patrol near here was one week ago. Sometime between now and then is when this must have happened, unless the last patrol did not spot the cave."
Luna bowed her head once, then looked back towards the cave. How the mouth of the cave could look so weathered despite being so new, she couldn't say. "What could have caused this that we would not have detected it?"
Celestia hesitantly lifted a forehoof, then stepped into the cave. "I do not know." She glanced back at Luna and studied her expression. There was the slightest hint of curiosity in her eyes, and her brow was creased, but otherwise, she looked normal. She smiled at her. "Shall we investigate?"
Luna hesitantly nodded. "If there is something amiss here, then it would be best for us to investigate," she agreed.
Celestia turned back to face the cave, then calmly strode into the darkness. Luna followed behind her casually, eying the rough rock walls. Celestia continued deeper into the cave, careful of her steps. She constantly looked around, pointing her horn at the walls and casting her aura so she could examine the rock. She stopped, then lifted her right foreleg and placed her hoof against the rough wall. Even with the golden shoe on her hoof, she could still tell that the rock was rough and uneven, yet worn so it wasn't sharp and jagged. "If this cave is new, then the rock should not be so weathered."
"And the rock is weathered, despite the cave being a recent formation," Luna noted. She looked around curiously and walked on past her sister. "When did you first... sense something amiss?" she asked. A second passed in silence and she looked back at her sister.
Celestia had her head tilted slightly to the side, and there was a pensive look on her face, with her brow furrowed in thought. "I... can't say. There is some magic here that is foreign, yet it feels familiar."
Luna frowned and looked back into the cavern. Her blue aura shined into it, but unlike her sister's golden aura, it provided much less light. "I still do not sense any magic here, sister."
Celestia nodded slowly, then walked over to Luna's side. "It's faint, almost like it's part of the background like it's been here for a while."
"Could it have been here the whole time and we just did not sense it?" Luna inquired.
"I do not know," Celestia answered. She pursed her lips as she thought about it, then unsurely shook her head and took a few short steps into the cavern. She shivered from the cold. There was a sharp temperature difference between the cavern and the outside. Even the difference between the cave and the cavern was enough to make her glance around to check for ice. She could almost see her breath.
Luna calmly strode on past her. "'Tis only a slight chill, Tia."
Celestia grimaced and watched her sister. The younger alicorn walked on past her, carrying herself with a slight hint of pride or superiority. Celestia stared blankly from where she stood as Luna took the temperature difference so casually as if it was a cool breeze in the summer. She swallowed back a tightness in her throat.
It took Celestia a few seconds to recover. She shook her head hastily, then shifted her weight and quickly strode ahead. The cavern was easily large enough for two full grown dragons to fit inside, and that was plenty of space for both of them to fly around if it proved necessary.
The cavern looked like a dome had been carved out of the mountain. Both of them swept their heads around to examine the cavern more closely. The walls did reflect the light from their horn slightly, causing the whole cavern to have a sort of ominous glow to it from the light of their horns.
Celestia walked over to one side and placed her hoof on the wall. It sounded like rock, rather than metal, but it undoubtedly was more reflective than normal rock should have been. "Crystal?" she mused aloud.
Luna glanced over at her. "Perhaps the rocks are infused with it, but this mountain shouldn't have any rocks of that nature," she replied. She made her way over to Celestia and looked over the rock with her. "It doesn't look like crystal," she noted. "If it was a rock rich in crystal, it should be lighter in color and be glistening or glittering from the light of our horns."
Celestia nodded absently, then pulled away from the wall and swept her horn around. "I sent a patrol to investigate when I first sensed it, and they reported this, but I'm not sure that was actually when I first sensed the magic," she commented. "It feels like it has been here for a while and I just did not notice it or think of it."
"Could this simply be Discord's doing?" Luna asked. "It wouldn't be beyond him to pull a prank like this..." she muttered under her breath.
Celestia pursed her lips, then looked around, halfway expecting the draconequus to pop out of her ear or her sister's ear. "We would have sensed him using chaos magic to create this," she stated. She slowly walked back to the center of the cavern and looked around, searching for anything different from the rest of the unmarked cavern.
Almost directly across from the cave entrance, there was an area of the rock which was discolored. Celestia turned to face it, then tilted her head. The rock looked even smoother than the rest of the rock, and it was darker than the surrounding stone. She looked back at the cave entrance, then traced a line from it straight to the door, then she glanced up at the very top of the dome, then at the sides.
She looked around and used her magic, then found the center of the cavern. Walking straight from the cave to the discolored rock would have went through the exact center of the cavern.
She fluffed her wings at her sides, then cautiously approached the discolored rock.
"Sister?" Luna asked.
Celestia continued towards the rock. "This rock isn't right. The color is off, and it's a straight line from the cave. It goes through the center of the cavern," she replied.
After a few seconds of walking, she stopped and looked over the rock. Her sister's hoofsteps gradually grew in volume as she studied it. The discoloration seemed to perfectly meet the rest of the rock, but it was also more reflective. She placed her hoof on it. Instead of a dull thud, her shoe clicked against the material. "This is metal," she stated. She looked over the edge where the rock and metal met. "And this appears to be a perfect rectangle," she added.
Luna pursed her lips as she looked over the metal from top to bottom. There was a slight glint which caught her eye. She looked further right. A few feet away, lying against the stone wall was a bell of some kind. She blinked in surprise and then frowned. She broke away from her sister, then walked over to the bell and picked it up with her magic. It made a slight cheerful tingle from being moved, drawing her sister's attention over to her.
"What is that?" Celestia asked.
Luna studied the bell, then turned back to Celestia. "This seems... familiar?" she asked. She rotated the bell around and studied it. The bell was made out of gold and barely had any openings in it. Looking at it from the bottom, there was an X-shaped slit on it where the gold all came together. "How did this even get here?" she asked aloud.
Luna jostled the bell again and listened to the chime. It sounded sweet and gentle. Something about it was soothing and comforting. She couldn't shake the feeling that she knew the sound from somewhere. It was like a dream or an old memory. She levitated it around and looked at the top, hoping for something to help her identify it, but if it had ever been attached to anything, it had since been destroyed.
Celestia nodded slowly, frowning in apprehension. "It does seem familiar," she agreed.
Luna shifted her weight and glanced at her sister. "I would say this warrants further investigation," she stated. Celestia nodded in agreement. Luna looked back at the wall, then teleported the bell away in a flash of magic.
"Perhaps this cavern isn't new after all," Celestia commented. "Somepony has been in here before."
"Indeed," Luna agreed. "But how was it somepony was able to access this cavern?"
"Perhaps further investigation will yield results," Celestia replied calmly. She lifted her forehoof and touched the metal with her shoe. She looked back and forth across its smooth, unscathed surface, looking for any blemishes, only to find none. She slowly slid her hoof downward, dragging her golden shoe across the metal. It barely made any sound. Luna looked at her curiously but remained silent.
Celestia pulled her forehoof back, then pulled the shoe off and touched her bare hoof to the metal. It was cold to the touch, much cooler than the cavern. She slid her hoof to the left and touched the rock. "The metal is cooler than the surrounding stone," she noted.
Luna frowned. "They should be the same temperature." She looked at the metal, running her eyes across the surface, then shook her head. "I do not see anything which would reveal a way to get past this."
Celestia put the shoe back on her hoof, then took a few steps back and surveyed the wall for anything they could have missed earlier. "Perhaps we could cut through it, or the surrounding stone."
Luna looked at Celestia wearily. "You know even better than I that some things are sealed for a reason, Tia," she cautioned.
Celestia grimaced and looked at her, nodding solemnly. "I know, but I feel as if we are meant to open it," she said quietly. She studied Luna's expression for a few seconds. While her sister nodded at her, she looked wary. Celestia exhaled and looked back at the metal.
"I will defer to you, sister, but I suggest we err on the side of caution," Luna replied. "Perhaps the cavern has yet more clues for us to discover."
Celestia nodded. She turned around, then looked up at the uppermost point of the dome. She closed her eyes and channeled more magic into her horn. The glow of her aura illuminating the cave grew as her magic coalesced into a bright yellow orb at the tip of her horn. After a few seconds, the orb popped off of her horn. She opened her eyes to see the room flooded with light from the orb. She grasped it in her magic, then levitated it up to the top of the dome and hung it there with her magic.
With the added light, the two looked at the walls, searching for anything amiss. While the brighter light source banished the eerie glow, there still wasn't much to see. The room looked like a perfect dome had been excavated from the mountain. The rock was different from the rock making up the cave. Despite the added light, the rock was still darkened, yet the cave seemed to take on an otherworldly glow, as if the light flooding the room was slightly off-color, having a teal tint.
Luna frowned. "The rock is fuzed," she stated. "That's why it looks strange. There was magic at play with the creation of this..."
Celestia frowned and studied the rock walls, probing it with her magic. She blinked. "I... cannot make anything out of the material."
Luna glanced at her sister. A moment passed, and a look of bewilderment crossed her expression. "Nor can I, sister."
Celestia fluttered her wings, then looked around and walked in a short circle. "This cavern is definitely artificial... but the cave... that cannot be a coincidence."
"What of the magic you sense? Was that responsible for this cavern?"
Celestia shook her head. "No, it's... not." She tilted her head to the side and pursed her lips. "The magic... it's... rhythmic. It's... a constant, repeating pulse... There seem to be several seconds of... less emission between the pulses, but it's still there."
Luna frowned. "Can you determine anything specific about the magic or the pattern? Perhaps there is a message to it."
Celestia shook her head. "I can't tell."
Luna took a deep breath, then slowly exhaled. "And you are sure that it's coming from here?"
Celestia nodded once, then turned to face the metal wall. "Yes. I cannot pinpoint the source, but it is coming from around here."
Luna looked at her warily. "Are you certain that this cavern is involved?"
Celestia looked aside at Luna. "Do you really believe this could be a coincidence?"
Luna shifted her weight on her hooves. "I am simply attempting to rule out other possibilities."
Celestia inhaled deeply and walked back to the metal. "This is clearly artificial, but it doesn't seem to have a purpose. Why would somepony create a cavern such as this with one section of the walls made out of a metal neither of us have seen before?" she asked in a curious voice. Her eyes wondered over the smooth surface. "And the metal is so... perfect," she said tentatively. "Why would somepony put this here? Why go to the effort? And why are we unable to figure this out?" She turned her head to look at Luna.
Luna wore a cautious expression. "Perhaps... this is somehow related to that expedition Twilight went on?" she offered hesitantly.
Celestia frowned. "That ruin in the Badlands?" she asked. Luna nodded. Celestia grimaced. "I should have sent Spike with her, then we could ask her about her progress and inquire about this cavern. I haven't heard from her since she left, but I am not surprised."
"Are you worried about her?" Luna inquired.
Celestia shook her head. "No," she said simply. She parted her lips again but hesitated a few seconds. She closed her eyes and lips, then shook her head. She opened her eyes once more and then scrutinized the metal. "Although I do look forward to her return. I'm sure she will have a lot to tell, and I look forward to hearing all about it," she stated. She looked over at Luna. "Why would you think that this is somehow related to that ruin?"
Luna shifted her weight on her hooves. "The fact that the ruin was discovered so recently, and then we discovered this so soon afterward. It may be a stretch, but perhaps they are somehow connected."
Celestia frowned a little. "I suppose it is uncommon for ancient ruins to be discovered in a short period of time, however, the distance between the two is significant. We don't even know if this is from the same time period as the ruin Twilight is investigating."
Luna nodded. "Twas just a thought, sister," she relented.
Celestia nodded idly, then turned her head back towards the metal. After a few seconds, she turned to her right, then slowly walked to the far left side of the cavern. She closed her eyes and sent a pulse of magic from her horn, then she opened her eyes and calmly walked to the far right side of the cavern. She repeated the pulse of magic, then she walked back over to Luna and the metal. "The source of the magic is coming from somewhere behind that," she stated, inclining her head at the metal.
Luna frowned. "Why didn't you do that before?" she asked warily.
Celestia grimaced. "I did not think it would work. The cavern is heavily shielded from magic, and the metal seems to be even more shielded. Whatever the magic I am sensing is, it must be very powerful in order to seep out. It isn't simply from the background. Whatever lies behind that metal, it is sealed in, but still leaking through."
Luna walked over to the metal, then stopped. She levitated her right shoe off of her forehoof, then she gently pressed her forehoof against the cold metal. "If you intend to further investigate this, then we will need to determine how to get inside," she stated.
Celestia nodded slowly, then approached the metal and stopped before it. She looked over it with her eyes and slowly shook her head. "There's nothing here to point at how to open this. It doesn't even look like it is meant to open. It looks solid, like a single piece of metal."
"Perhaps it is a seal of some kind," Luna offered. "We still have many options at our disposal if you wish to break it. We could excavate the surrounding stone and attempt to learn more about it, or we could break through it."
Celestia nodded absently. "Perhaps we are still missing something. Maybe it is something obvious..." she trailed off. "That bell was familiar, but... I do not see how it could be tied into this, if it is a seal," she stated.
"The bell may not even be related to this," Luna acknowledged. "For all we know, it could have been somepony exploring who stumbled into here and discovered this. Perhaps they, like us, were unable to open it."
Celestia grimaced, then took her right shoe off of her hoof and touched her forehoof to the metal again. "I can't help but-" A dull thump rang through the air, and the mass of metal seemed to pop to the side. Celestia pulled her forehoof back and looked at the metal plate with bewilderment. "What?" she asked. She blinked, then looked over at Luna.
Luna looked over the plate of metal cautiously. She slowly pulled her bare hoof back from the metal and turned her head towards her sister. "It would seem... that both of us were required to unlock it..." she trailed off at length.
Celestia's brow creased in thought. "Then this was intended for us... the magic doesn't feel any stronger. It is still sealed inside somewhere, but there is more here..." she trailed off.
"Shall we investigate?" Luna inquired.
Celestia nodded. She lit her horn and looked over the metal. There was a slight crack on the left side, going from top to bottom. It was just barely noticeable, and it seemed like the rock hid more of the metal. She gripped the door with her magic, then slid it to the right. Despite expecting the screeching of metal on metal, the door made no sound as it easily slid open. A wave of icy coldness washed over her and Luna as the temperature difference stirred the formerly sealed air. Celestia could see her breath in the cold air, but it quickly faded as it mixed in with the warmer cavern air. Beyond the doorway was a long, dark hallway. The walls were made of a dark metal, the same kind that the door was made out of. Every few feet, the metal was broken by what appeared to be a single crystal which was embedded in the wall, going all the way up to the ceiling from the floor, across to the other side, and then down to the floor again.
Luna felt a tingle run down her spine. "This is... unfamiliar, sister. I... do not recall ever encountering anything quite like this..." she trailed off.
Celestia slowly nodded in agreement. She kept her horn lit, then slowly took a step forward. She stepped into the hallway and looked around. The walls were devoid of distinguishing features, save for the crystals. She shifted her weight, then slowly made her way deeper into the hallway. After a few seconds, she heard Luna's hoofsteps following behind her. Even with the light of their horns, the hallway still looked dark.
Celestia paused, then looked down at the floor and studied it. Where she had expected to find dust and debris, evidence of just how long the structure had been abandoned, she found a pristine, perfectly cleaned floor. She looked back up and peered down the hallway, which seemed to come to a complete stop about twenty feet away. Luna came to a stop beside her, and after sharing a brief glance, the two cautiously proceeded. As they neared the end of the hallway, they could make out what appeared to be two doors, one on each side of the hallway at the end.
But what drew more of their interest was the short pillar at the end of the hallway with a single, smooth, light blue crystal set into the metal. The crystal was circular in shape and rounded so it stuck up from the metal slightly. It looked so pure and perfect, and where it met the metal appeared seamless, almost as if the crystal and metal had grown together.
Celestia came to a stop and studied the crystal with her eyes. Despite the pure, perfect look, it somehow seemed dead and lifeless. She frowned a little, then touched her bare forehoof against it. The crystal was cold and felt as smooth as it looked, almost like glass. She slid her forehoof off of it, then looked back towards the entrance. In a flash of yellow light, she teleported her shoe back and slipped it back on. A moment later, Luna a flash of light blue light signaled Luna doing the same.
Celestia took a deep breath and looked around, studying the wall behind the pillar. What she saw made her shiver. On the top left of the wall, equally spaced from the top and the left, there was a yellow crystal shaped like a sun. A very familiar sun, while on the top right was an equally familiar crescent moon-shaped white crystal.
"Tia... what is this?" Luna asked cautiously.
Celestia remained silent as she looked at the two cutie marks in between theirs. One was old, far older than the largest one in the center of the wall. The old cutie mark was directly above the larger one and set in between theirs. It brought back fond memories to her mind, carefree summers, warm fires in winter, and an aged stallion who had devoted his life to studying magic. She swallowed and licked her lips, then looked at Luna.
Luna wore a weary expression. She looked hesitant and caught off-guard by the four cutie marks. She reluctantly pulled her gaze away from the wall and looked at Celestia. "The bell..."
Celestia nodded. "Starswirls," she stated. "I knew it was familiar, but... I couldn't place it."
Luna squinted. "Why would that be here?" she asked.
"I believe we've found something which Starswirl found... do you remember when he disappeared? The first time, when he went looking for something. Before that, he spoke of something his mentor had said... I... don't remember what it was... When he came back, he had lost the bell on his hat," she stated.
Luna nodded slowly. "Yes, I remember that." She tilted her head to the side. "It... was something about... prophecy, I believe?" she asked.
Celestia nodded. "Yes, but I was thinking of the other thing he mentioned. Something about..." She squinted. "An alicorn war?" she asked. She shook her head.
Luna frowned. "Sister?"
Celestia pursed her lips. "Come to think of it... that was thousands of years ago, and I have never since, nor before, heard anything of an alicorn war," she stated.
"Why do you bring this up, sister?" Luna asked.
"I'm... not sure. I just know that Starswirl was looking for something his mentor told him about before he disappeared. He never did speak of what he found when he returned, or if he found anything..."
"If he was here, then he found this, but then why wouldn't he mention this?" Luna asked. A grimace pulled at her lips. "We both know he would have eagerly spoken of this place if he had found it."
Celestia was silent. She inclined her head towards the large cutie mark in the center of the wall. "What I'm more curious about is why Twilight's cutie mark is here," she stated.
Luna's eyes trailed over the crystal representing Twilight's cutie mark. It looked like a perfect replica, the pink six-pointed star in the center with white crystals adding to the starburst, and five white, six-pointed stars surrounding it, in the same pattern as on Twilight's flank. As she looked at the outer stars, she saw a leather-bound book lying on the floor. She frowned, then lifted the book up in her magic.
Celestia's gaze drifted over to the book held in Luna's magic and she stared at it. "That's... one of his journals. It looks like the one he took with him..."
Luna grimaced and brought the book closer to her. "That would explain why we never found his journal of his search," she stated. She looked over at Celestia. "Do you wish to read it now, or shall we wait until we have identified the source of the magic you're sensing?"
"He will likely have written extensively on his findings here in his journal, so it would be beneficial to see what he has to say," she stated.
Luna nodded, then looked back at the book. She quickly scanned it over with her magic to make sure there weren't any spells in place which would damage or destroy the book if she opened it, then she opened it. She blinked and frowned in bewilderment. "The... pages are torn out."
"What?" Celestia asked. Luna levitated the book over to her. She looked over the binding, seeing that at least a dozen pages of the book had been unevenly torn out, leaving plenty of evidence of their existence. The rest of the paper in the book had yellowed and was fragile, but plainly blank. "Why would he do that?" she asked herself in disbelief.
Luna slowly levitated the book back over to her. "I... do not know. Perhaps he did not do it?" she offered. After a moment, she grimaced and teleported the book away. "I suppose that this means we will be going into this blindly," she stated. She looked over at Celestia to see her wearing a distressed look.
Celestia reluctantly nodded. She hesitantly looked at the left door, then at the right door. She nibbled on her lip and used her magic to try to identify the source of the magic she felt. After a few seconds, she turned to the right and walked behind Luna and made her way for the door on the right. Luna turned and watched her.
"This one," Celestia stated. She looked over the door, studying it for a way through. The door seemed to split into two in the center, seeming to indicate that the two metal plates would slide away from each other, retreating into the wall when activated. To the right of the door at her chest height, there was a tall, smooth oval-shaped crystal. It was set in the wall but raised above the surrounding metal. The light-blue crystal looked like it could be removed, but she didn't want to try. She studied the crystal with her magic. "The crystal is a control," she stated. "It's inert. I may be able to restore it," she added.
She focused her magic on the crystal, examining it more closely and studying the inert spells it held. After about a minute, she poured magic into the crystal, making it glow to life with a light blue light. She studied the crystal's spellwork to determine how to activate it, but the complex spell resisted her probing. She frowned and let her aura disperse, then cast a glance back at Luna. "Any ideas?"
"There is more than one way to open a door, sister," Luna offered. She lit her horn and grabbed the door in her magic, then gradually pried the twin plates of metal apart. The metal groaned under the strain as it resisted, but in the end, it was no match for the moon princess's powerful telekinesis. As soon as the doors started moving apart, they practically launched into the walls and jammed, making it unlikely the doors would ever be closed again. Luna smirked a little.
Celestia shivered as yet another wave of cold washed over her. Before she could take the lead, Luna strode on in before her. She watched her younger sister for a few seconds, then followed behind her. The younger alicorn swept her horn around, carefully scanning for any potential threats while Celestia followed behind her, examining the walls for any details which could provide clues. She paused for a moment, then created two smaller orbs of her magic. The magic burned brightly and lit the hallway for them, providing nearly as much light as the orb she left in the cavern. She took one of the orbs and teleported it above the pillar in the previous hallway, then she levitated the remaining up to the top of the middle of the hallway.
The light illuminated almost the entirety of the hallway. At the end of the hallway was a single door, and the walls were barren, save for the occasional crystal breaking it into sections.
Luna continued to cautiously lead the way into the cold until the pair arrived at the end of the hallway. With the same ease as before, Luna ripped open the doors at the end of the hallway.
A single small room greeted them. The room looked large enough for maybe eight alicorns of Celestia's size to occupy. The room was far from spacious, and it looked more like a storage closet than anything else. The room was square, yet the floor had a single large crystal set into it. The crystal was circular and flat, large enough that the sides touched the midpoints of the room's four walls.
Luna frowned. "This isn't what we are looking for?" she asked.
Celestia studied the walls. The center of each of the three walls had a single pink starburst crystal set in them. She could sense the magic coming from the room, yet it was no stronger than outside of the cavern. "It... is..." she said hesitantly. "But... I don't understand. The magic should be far stronger than this," she stated.
Luna stepped into the room and looked around. She noted the crystals, but aside from them, the room was empty.
Celestia reluctantly walked into the room and stood beside her. She looked along the edges of the walls where the met the floor, then she turned around and looked back down the hallway. A single piece of paper caught her attention near the base of the door. She frowned, then took it in her magic and studied it.
The paper had yellowed and looked fragile, but most importantly, the left side was unevenly torn. "Luna," she called.
Luna turned around and looked over the page. "That's one of the pages from his journal," she noted.
Celestia brought it closer, then looked over the ink. She smiled a little. "Definitely his hornwriting," she giggled. The writing was somewhat sloppy, written in a hurry, and in the language of Old Equish. She couldn't help but smile. She flipped the page over, expecting to see more writing, but the back was blank. She frowned a little and turned the page back around, then read it over. She slowly lifted her head up and stared back at the pillar in the first hallway. She levitated the page over to Luna for her to read.
After a few seconds, Luna looked over at Celestia. "He mentions finding an incomplete spell here, but doesn't say anything about it?" she asked. "No description and the actual spell isn't here... I do not remember him ever speaking of finding an incomplete spell and finishing it," she stated. "Perhaps he never completed it?"
Celestia nodded slowly. "There were dozens of spells Starswirl never completed, but he never said that he found any of them. He always tried to create new spells..." she trailed off.
"How are we supposed to figure out what spell he found if he never admitted that he found a spell?" Luna asked warily.
"Simple," Celestia replied. She teleported the page away and took a deep breath. "It would be a spell which he couldn't complete, not for lack of desire. A spell he wouldn't be able to understand. A spell that would make no sense for him to try to create," she stated. She looked over at Luna. "The same spell Twilight finished."
Luna squinted at Celestia and shifted her weight on her hooves. "How... would you know that?" she asked slowly.
"It never made sense to me why he would have created a spell which involved friendship. He wasn't exactly a pony who would have wanted to be an alicorn, either. So why would he try to make a spell which involved friendship for the explicit purpose of ascending to alicornhood? It never made sense... I never understood it..." she trailed off, her eyes darting back and forth.
Luna reluctantly nodded. "So... not only did Starswirl investigate this... ruin, but it contains our cutie marks, his, and Twilight's... And he found the spell which Twilight completed here... And it just so happens that we find this as Twilight is investigating a ruin in the Badlands which has her cutie mark in it..."
Celestia looked over at Luna.