About an hour had passed since Twilight sent a letter to the princesses, unfortunately they have yet to send a reply, Twilight simply chalked it up to their busy schedules.

Finally giving in to her curiosity, she decided to check up on her otherworldly guests while she waited. She was particularly intrigued by Spike's report on what Midnight did to their room, turning it into a library that's larger than the castle's own should be impossible, or at the very least, incredibly difficult unless you're somepony like Discord.

Just how much magical knowledge and power did those three possess?

She made her way to the guest room where the trio were residing in, only to find the door completely changed. In place of the usual pony-sized purple door, there was large, metallic circular door imbedded into the location where the original entrance should be, easily as tall as four ponies. Twilight realized it resembled the door of a bank vault.

The metal frame of the door was lined with strange glowing glyphs with colors that alternated between cyan, yellow, and red. The door itself was in a similar state, multiple glowing glyphs were engraved in a circular pattern surrounding three symbols placed in a triangular position at the center of the door itself.

The topmost symbol caught her eye, it bore a striking resemblance to her cutie mark, a six-pointed starburst. The only difference it had to hers was its vibrant cyan color and a smaller similarly six-pointed magenta colored star overlapping it instead of the being covered by the bigger one, with the points alternating between the bigger and smaller stars just like her own, the parts where both stars overlapped combined into a deep blue color. She assumed it was Midnight's cutie mark.

'Even more support on the parallel world theory' Twilight thought.

The symbol to the bottom left looked like the letter 'X', with its upper and lower ends curled, spiraling outwards. It was colored yellow that faded to black as it reaches the ends of the symbol. Twilight remembered seeing it on the large bell on Grogar's harness.

The last symbol on the bottom right was an eight-pointed starburst of various colors, with its vertical and horizontal points being longer than the diagonal points. By process of elimination, Twilight recognized it as Cosmos' symbol, though she hadn't seen it anywhere on Cosmos herself.

"Well, that's definitely... something." she mumbled to herself.

She knocked on the door and waited for a response, each knock made a low reverberating sound.

A moment passed with no reply.

When nopony answered, she tried to knock again. This time, however, there was a loud whirring noise that came from the door, followed by the sound of pressurized air being released from the frame. Suddenly, the door jerked ever so slightly downwards and eventually smoothly lowered itself into the floor, which, Twilight remembered, was supposed to be made of solid crystal.

What surprised her even more was the sight of a tall, imposing, looming figure of an alicorn looking down at her with their violet eyes and faintly glowing cyan sclera. The unexpected presence of the tall alicorn causing her to jump.

"M-Midnight!"

"Hm? Oh, hello princess, do you require any assistance from us?" Midnight casually asked from the doorway, not realizing she unintentionally jumpscared Twilight from her sudden appearance.

Twilight took a breath and quickly calmed herself, "Um, actually, I wanted to check up on you and your friends. Spike told me you did some, er, 'redecorating', so to speak, so I wanted to know if everything's going well."

"I see, well, I believe I may have frightened him when I manifested the first layer of our quarters. For that, I apologize." Midnight said as she bowed her head.

"It's fine, Midnight, you didn't actually scare him, I'd say you just surprised him more than anything else." assured Twilight.

"That is good to hear. Anyway, would you like enter and see what we have done with our given quarters, princess?" Midnight asked.

"Yes, if you don't mind, that is."

"Princess, you have been nothing but helpful and amicable to us since we first arrived in this world, know that you are always welcome in the Archives of the Forsaken Triumvirate." Midnight said as she stepped aside and motioned a wing around the interior of the room.

Twilight slowly walked into the room, she flinched slightly to the sound of the door closing behind her. Realizing what Midnight just said, she turned her head back to the taller alicorn, "Is that what you call yourselves?" she asked.

"Cosmos came up with that name as we were reforming the room, I still do not understand why she chose 'Triumvirate' specifically, since we do not hold any form of authority, well, anywhere." Midnight shrugged her wings and walked away from the door.

"Oh..." Twilight turned back and was immediately astonished by what she saw.

Spike wasn't exaggerating when he said it was 'gigantic'. Before her, was an expansive, circular room. Its diameter surpassing that of the castle's throne room. Bookshelves filled with countless books covered the entirety of the walls, practically replacing it. They were standing upon a platform that surrounded the inner walls of the room, with four pathways that connected each opposite end of the room with each other and meeting in middle, leaving quarter circle-shaped gaps guarded by rails.

At the center of the room was a large plate-shaped device, which was holding a floating set of spinning and twirling rings that were nested within each other, which in turn were containing a brightly glowing red orb inside them, all within an enclosed, round, cyan-colored magical field as big as the entire device itself.

Looking beyond the device, Twilight saw what looked to be a large glass screen, which was imbedded into the now non-crystalline wall. Below it was a series of various buttons and switches.

Twilight then shifted her gaze upwards, which revealed more full bookshelves and other platforms beyond the platform they were on, going way beyond the supposed maximum height of the castle.

Excited, Twilight went towards one of the gaps and peered downwards from the railings. She was met with the sight of even more bookshelves and platforms going beyond what should be solid ground.

Twilight looked back at Midnight with an amazed expression, "This... this is incredible, Midnight! How did you all do it? This should be impossible!"

Midnight chuckled in amusement at the young princess' foal-like wonder, "Impressive, is it not? You see, princess, due to my purpose of forging stars and decorating the heavens with them, I was gifted by Lady Faust, my creator, with a high affinity for reality magic, which is a form of magic that allows the user to, well, warp and bend space to their will. The only other beings who are capable of casting such magic without causing the immediate area to collapse upon itself and who are not spirits of Hades such as Cosmos, would be Lady Faust herself, and Trixie Lulamoon, the Peacekeeper of Reality and one of my dear sisters." Midnight explained, radiating an aura of pride when she mentioned her sister.

Listening to Midnight's explanation, Twilight's mind became a whirlwind of theories and questions. Lady Faust? Reality magic? Spirits of Hades? Trixie is her sister?!

"Wait wait wait, Trixie is your sister?!" Twilight asked, absolutely dumbfounded.

Midnight looked at the smaller alicorn with a raised eyebrow, "Yes, she is my sister. Is there something wrong, princess?" she asked, her tone was oddly defensive.

Twilight noticed this change in behavior and decided to share her thoughts, she didn't want Midnight to misunderstand her, "I mean, well... you see, Midnight, I've had this theory that maybe the world you and your friends are from what might be a parallel world or alternate dimension to this world, in a way. At first, this theory was mostly based on how our voices sound similar, but that didn't really mean anything, it could've just been a coincidence. Then, Fluttershy mentioned that this world had its own Grogar who was a villain from a storybook, and if the theories from scholars about said book are true, Grogar was a real figure in Equestrian history. It was more evidence, but there still wasn't enough to properly support the theory.

"Later, when I came to check up on you, I saw on the door how similar your cutie mark is to mine, give or take some details, which of course, was more evidence for the theory. And then, during this conversation, you mentioned the full name of a pony who's their own unique individual here. Could you possibly describe how she looks and acts?" Twilight finished her explanation with a careful question.

Midnight paused and put a hoof to her chin in thought, "Hm... well, I am afraid I am not very good with physical descriptions, princess."

"Just try to the best of your abilities. If I can get at least some kind of description of your Trixie, I can compare her with the information I know of Equestria's Trixie." Twilight encouraged her.

Seeing the smaller alicorn's hopeful look, she gave in, "I shall try, princess." she started to pace around the platform, "Let us begin with her behavior, she can be quite the braggart at times, this is a source of contention between her and the beings she makes contact with; she is very determined, once she focuses on an objective, she will not stop until said objective is completed; many would consider her to be quite eccentric due to her interest in 'performing', as she likes to say; and she has a tendency to speak in third being.

"For her physical description... her coat is a shade of blue, somewhat pale, but still quite vibrant... I suppose?" Midnight said hesitantly.

Twilight looked around the room to find an example, she took out a book from the wall and held it in front of her, "Like this?"

Midnight nodded, "The very same color as the cover."

Sure enough, it was colored in a familiar shade of azure, the same color as the coat of certain showboating unicorn.

Midnight continued with her description, "Her mane and tail are... silver? With a hint of blue. There are lighter streaks among the darker hairs. Being a transcendent alicorn like I am, her excess magical energy manifests through them, along with her horn, wings, and hooves; making them flow as if they were being constantly blown by wind. Though, she keeps her mane relatively short compared to mine and our siblings, as she finds it obtrusive."

Twilight returned the book and took out another one, "Are the colors similar to this?"

Its cover was colored pale cornflower blue.

Midnight nodded again, "Yes, but there are streaks of a lighter form of that specific color as well."

"Alright, so I guess that confirms it then, your Trixie is identical to Equestria's, excluding the fact that she's an alicorn with what I assume is a big role in your society. Your world is a parallel dimension to Equestria, or vice versa, it really depends on which one came first." Twilight clarified.

"That is quite the significant discovery, princess, I must inform Cosmos and Grogar of this revelation immediately." Midnight took a deep breath.

"COMPUTER!" Midnight suddenly shouted towards the upper levels of the archive, in a voice that Twilight assumed was Midnight's version of the Royal Canterlot Voice. This caused Twilight to cover her ears with her hooves and wings in a fruitless attempt at protecting her hearing.

Once the archives stopped echoing, a disembodied voice made itself known, "I have a name, you know." it said, displeasure clear in its tone.

Twilight found this voice to be quite familiar, she just couldn't put her hoof on it.

In a flash of light, an ethereal figure of a small alicorn mare appeared in front of them, she had an amber-colored coat, a two-toned mane and tail of bright red and yellow, cyan eyes, and on her flanks was a cutie mark in the shape of a red and yellow sun.

Midnight looked at the alicorn with an amused expression, "I know, but it gets your attention."

The translucent alicorn rolled her eyes and turned to the princess, who was owlishly staring at her, "You must be the pri-"

"Sunset Shimmer?!" Twilight blurted out, completely interrupting her.

Sunset blinked, and looked at Twilight with a raised eyebrow, "Okay, rude. And yeah, it's me, I'm guessing Midnight told you about me?" she asked, clearly annoyed.

Twilight flattened her ears and Midnight interjected before Sunset started ranting at the princess, "Not exactly, you see, Sunset, it appears that your initial calculations were indeed correct, we have travelled to a world that is parallel to ours, where beings who exist in ours also exist here, albeit with certain differences." Midnight looked back at the princess, "I take it your world also has a Sunset Shimmer?"

"Yes, but she's not an alicorn, she's a unicorn, and also a lot more... solid." she put a hoof to her chin, "Well, only a unicorn when she's in Equestria anyway, it's a long story." Twilight turned to the ethereal alicorn with an apologetic look, "I'm sorry for interrupting you like that, by the way."

Sunset's expression softened and she sighed despite not having lungs, "It's fine, it's fine, you're just shocked, I guess, parallel dimensions and alternate universes and all that jazz." she looked towards Midnight again, "Anyway, what do want, Midnight?"

"Could you notify Cosmos and Grogar to meet with me at the core room?" Midnight asked.

Sunset huffed, "Fine." she lit her horn and launched two red orbs which went above and below the platform they were on, "Could've done it yourself." she muttered under her artificial breath.

"But then you wouldn't have met Princess Twilight." Midnight told her.

Sunset rolled her eyes, "What else do you want?"

Before Midnight could say anything, the three alicorns heard knocking from the door, Sunset's eyes suddenly glowed brightly and then went back to normal, "Little dragon guy at the door."

"Spike?" Twilight looked towards the door.

"Let him in." Midnight told Sunset.

"Aye aye, captain..." Sunset replied sarcastically.

The door opened to reveal Spike, who stood there with an awestruck expression, "Okay..." he shook his head and looked into the room, "Uh, hey, Twilight, Midnight... Sunset?"

"This is gonna get annoying real quick." Sunset facehoofed and shook her head.

"U-um, the princesses are here, I told them to wait in the throne room" Spike said as he was staring at the various oddities within the room.

"Oh no, I totally forgot! Hold on, Spike, we need to wait for Grogar and Cosmos." said Twilight.

Just as Spike was about to reply, Cosmos arrived through a tear in reality that she opened up using her tail. Grogar emerged through a yellow portal from the ground not long after.

Cosmos looked around the round and at the assorted beings within it, "What's up, Middy?"

"Initially, I wanted to inform you of the revelation that the world we arrived in is an alternate version of ours, but it appears that we will soon have a meeting with the absolute rulers of this nation," Midnight looked towards the princess in the room, "is that correct, princess?"

"Yes, Princess Celestia and Princess Luna are the co-rulers of Equestria, I sent a letter to inform them about your unexpected arrival. Sorry about not telling you sooner, I sort of got caught up in... all of this." Twilight said as she rubbed the back of her head.

Grogar waved a hoof dismissively, "We don't mind, princess, I would honestly rather get this done with now than later. It's not often they get extradimensional immigrants, I'd imagine."

"Celestia and Luna... my nieces?" Midnight's eyes widened in realization.

Once again Twilight and Spike found themselves absolutely floored by the pieces of information Midnight casually shared, "Nieces?!" they both asked at the same time.

"Indeed," Midnight replied, "Celestia and Luna are the daughters of my sisters and fellow Guardians, Daybreaker and Nightmare Moon respectively. Despite being cousins, they are as close as sisters, many often mistake them as such.

"Always getting into trouble those two, to think, they would be rulers of an entire nation..." Midnight chuckled at the thought; it seemed Grogar, Cosmos, and Sunset shared the same sentiment as they snickered along with her.

'Just how crazy can her world be?' Twilight thought to herself.

Spike cleared his throat to get everybeing's attention, "Guys, princesses?" he pointed a thumb towards the direction of the throne room.

"Ah, right, let us go then, and Sunset? You may continue with your duties now." said Midnight as she and the other made their way to the hallway.

"No way! I gotta see what Cel and Lu are like as princesses," she lit her horn, and a floating saucer appeared above her, "alright, let's go!"

Midnight looked at her digital companion, "If that is what you wish."

As the group of assorted beings made their way into the throne room, they were met with the presence of the two members of the Equestrian diarchy.

Midnight, Cosmos, and Grogar bowed, Twilight and Spike joined on the princesses' side, and Sunset stood near the door behind her developers, watching it all unfold.

Princess Celestia told them to rise and greeted them, "It is a pleasure to meet you, Midnight, Grogar, and Cosmos, I am Princess Celestia, co-ruler of Equestria and Princess of the Sun."

Princess Luna stepped up, "And I am Princess Luna, co-ruler of Equestria and Princess of the Night, we would like to welcome you to our glorious nation, and we hope you've enjoyed your stay so far."

"We have, your highnesses, it's all thanks to Princess Twilight's help that we are able to find shelter immediately upon our arrival." said Grogar.

Celestia nodded in understanding, "That's very good to hear, I am actually glad you arrived somewhere within her domain, as I would say that she along with her friends are the most suited to dealing with situations such as these. I'd imagine if it were anypony else, they would have been frightened by the sudden appearance of three unknown creatures within their property."

Midnight nodded as well, agreeing with Celestia's words, "Yes, I doubt a simple mortal being would have been equipped to tend to three extradimensional visitors."

Twilight and Spike watched the conversation from the side of the princesses. Twilight was intently listening to the five beings converse when she felt a scaly claw poke her foreleg.

"Yes, Spike?" she whispered.

"Midnight's taller than Celestia." he whispered back.

"What?"

"Midnight is taller than Celestia." he whispered again, this time just a bit louder.

Twilight turned her head to the two tallest alicorns in the room. Sure enough, Midnight was about two and a half heads taller than Celestia, causing the extradimensional alicorn to look down from her position to make eye contact. This, like every other thing relating to Midnight and her friends, surprised her, how could she not realize?

The longer she thought about it, the more it made sense, though. Midnight claimed that Celestia and Luna were her nieces, it made sense that the older alicorn would be taller, Celestia is the oldest alicorn in Equestria, and she's the tallest pony Twilight knew. But that begged the question, just how old is Midnight? Twilight wanted to continue that train of thought, but it, along with the conversation between the royals and their otherworldly guests, was interrupted by a loud snort followed by giggling coming from the direction of the door.

Celestia craned her neck to the side to look beyond her three guests, only to find... Sunset, with wings, trying and failing to stifle her laughter with a hoof to her mouth, whose body had about as much opacity as a windigo.

"S-Sunset?" she asked tentatively.

This snapped Sunset into attention, she looked at Celestia in the eye and heaved a digital sigh, "Hoo boy, here we go..."

Celestia stepped closer to her with a sad look in her eyes, "Sunset, I-"

Before she was able to say anything, Sunset held up a hoof, "Okay, before we get into a perpetual loop of misunderstandings, I'm just gonna say it. I'm not the Sunset from your world, I'm from theirs." she said as she pointed to the trio with a wing.

Celestia's eyes widened, "What?"

Seeing Celestia's confusion, Twilight and Midnight decided to quickly explain to her and Luna about how Equestria and the trio's home world were alternate versions of each other, and that there are other versions of themselves living there, not unlike the mirror portal where Equestria's Sunset lives. Throughout her explanation both princesses seemed to shift between various expressions, such as confusion, intrigue, surprise, amusement, and more as they went on.

Luna nodded after the two finished their short lecture, "I see," she looked at the trio, "so your world is many times more advanced than our own, and there are other versions of ourselves in your world, in which your version Celestia and I are... your nieces? And are cousins?" she asked Midnight.

"Yes."

"And I am the daughter of Nightmare Moon?" Luna added.

"Correct." Midnight verified.

Luna then turned to Sunset, "And you were our foalsitter?"

Sunset nodded, "Yep."

Celestia rubbed the bridge of her snout and slowly shook her head, "This is... a lot to take in, the world beyond Starswirl's mirror was at least a lot more straightforward."

Midnight looked at the solar princess, "Starswirl? A version of my brother exists here too, I see."

The three princesses and baby dragon could only stare in shock.

"Brother?!" Twilight nearly shouted.

Spike threw his arms in exasperation, "Just how many siblings do you have?"

"Including myself, there are twenty of us. We are collectively known as the Guardians of Tellus. We were all created by Lady Faust, The Beacon of Creativity, to maintain and protect the realm of Tellus in the name of Existence and Creation." Midnight explained, "At least, we were supposed to." she lightly stamped her hoof and ruffled her wings. Cosmos put a hand on Midnight's withers to calm her.

Grogar decided it was time to chime in. "Cosmos and I possess similar roles for the forces of Hades and Oblivion respectively, we too, have our own groups dedicated to maintaining and protecting Tellus under their names. I am a part of the Heralds of Oblivion, while Cosmos is a member of the Ballasts of Sanity."

Luna nodded, "I see, and you were all members of high ranking, I presume? Considering the feats of magic that Princess Twilight had told us."

Grogar stroked his beard in thought, "For the Heralds? Yes. The title of 'Embodiment of Oblivion' is bestowed upon the most experienced and well-versed in void and primal magic, while the Guardians consider themselves equal," he heard Midnight snort in contempt, "as for the Ballasts..."

"The Ballasts choose the spirit with the least comprehensible creations for Impossibility and the most stable creations for Probability, that's why I'm the Avatar of Impossibility." Cosmos completed his sentence.

Luna then turned to Sunset, who was using her wings to hold a device that seemed to control the movements of a pony character that appeared on a floating screen in front of her, Luna seemed interested, for a moment, "And as for you, Sunset?" she asked.

Sunset dismissed the device and screen to look at Luna, "I'm a sapient Artificial Intelligence that was developed by those three numbskulls," she pointed a wing at the trio, "because they're too lazy to do anything."

"Artificial intelligence?" Luna inquired.

"Tech stuff, Equestria's not at that level of advancements yet." Sunset explained unhelpfully.

"Very well then."

Celestia stood up straight and walked over to the trio with Twilight and Spike, "Unfortunately, I believe it's time for Luna and I to return to Canterlot, we apologize for the inconvenience." she said to the extradimensionals.

Midnight waved a hoof, "Of course, your highness, you must be very busy with duties. I must admit, it feels quite surreal to see my nieces, who are typically quite unruly, become wise leaders of an entire nation."

Celestia chuckled, "I agree, I also find it fairly surreal that a former student of mine was my foalsitter." she smiled at Sunset.

Luna walked over to the door, "Farewell, everycreature. May we meet again soon." and left the room.

Celestia walked up to the door as well, before turning around, "Midnight, Cosmos, Grogar, please understand that if you ever have any trouble in adapting to Equestria, or have any questions pertaining to it, we," she waved a hoof at Twilight and Spike, as well as herself, "will always be there to help you."

Midnight smiled and bowed her head, "Understood, your highness."

Celestia continued her way to the door and looked at Sunset, "Goodbye, Sunset." she said with a sad smile.

The ethereal alicorn smiled back at her and waved a hoof, "Bye."

When Celestia finally left the room and closed the door, Sunset looked to Twilight and Spike with a confused expression, "What was that about?"

"It's... a long story." Twilight said hesitantly.

It was sometime later when the co-rulers of Equestria arrived back in Canterlot, they were now walking through a hallway, deep in conversation about their visitors from another world.

"What do you think, Tia? An alicorn, likely older than us combined, practically overflowing with magical energy, from an alternate universe, no less, who is friends with a spirit of a similar nature to Discord, and a powerful sorcerer who ponies may recognize as a villain from legend, along with full mastery of technology beyond our comprehension, just living in a small peaceful town and acting like nothing is out of the ordinary?" Luna asked her sister.

"Midnight said that they simply wish to continue living peacefully, you read the letter Luna, they were betrayed by their own kind despite their undying loyalty to them. They've gone through a lot, and I don't want to rob them of the happiness they have. If anything, I believe that their presence here could help Equestria." Celestia shared her thoughts with her sister.

"Help Equestria? Is this like that time you tried to reform Discord with the Element Bearers?"

"It's similar, but unlike him, they never denied the magic of friendship, they have already embraced it, no need in reforming. They said they maintained and protected their own world, who's to say they can't do the same with Equestria?" Celestia continued.

"Then we'll need to gain their loyalty first." Luna countered.

"And that's why I think exposing them to Twilight and her friends would help them appreciate what Equestria has to offer." said Celestia confidently.

Luna looked at the mosaics as the two of them passed through the hallway and sighed, "I hope you're right, sister."

Author's Note

And here we have the debut of Holo-Sunset! She'll be appearing every now and then.
This chapter is full of exposition, but I assure you, dear readers, we'll be progressing the story again soon!

Next chapter: Discord stole Cosmos' Battlemace set?

If you want to share ideas on how this story should go, consider commenting!

Corrections and criticisms are more than welcome, I can't improve without those now, can I?
Have a good existence!
:)

"Remembered forever, the land of Equestria"