Something isn't right.

It was an absurd understatement, and Celestia would've laughed out loud had she not been so terribly uneasy. It was true that the hour of her return was nearly at hoof, and it was true that she still knew nothing about what had happened in that hospital earlier.

To add to the confusion, the three mares that had been brought in seemed to have outwardly recovered from whatever curse they'd been under, but Celestia knew better. She could still feel how their very presence seemed to warp, twist, and erode the ambient mana around them. Once she was informed of the change, she'd paid them another visit, upon which they'd all requested to be dismissed from what was effectively imprisonment within their own room.

Celestia, of course, had refused, putting on a caring smile and telling them they needed to be kept in the hospital so that the doctors could make sure there were no other complications from the mysterious 'illness'. After all, they knew nothing about what had happened, whatever had affected them could be contagious and/or deadly.

In reality the Solar Monarch simply didn't trust them to roam about on their own.

As strange and unsettling as all of that was, and even setting aside the return of her other half, there was something else bothering Celestia. As the celebration neared ever closer, she could feel the atmosphere becoming more and more tense, and she doubted it was because of her inevitable reunion.

No, there was something else about tonight that seemed to be making her and her little ponies nervous. Not only that, but Celestia herself felt like she was missing something important—something she desperately needed to figure out, or something she needed to remember. It was as though she'd experienced some strong sense of deja vu, but didn't know what the event was that had triggered it.

And so she sat on the balcony just outside her chambers, overlooking the city of Canterlot from on high. She watched the crowd of ponies that had gathered in the streets, waiting for their Princess to raise the sun on what was supposed to be a wondrous occasion. Even from a distance, she could tell many of them were restless, and she shared in that restlessness.

She scanned the crowd with a silent frown, a frown that only deepened as she turned her gaze towards the moon hanging low in the sky. It remained frozen where it was, waiting for her to assist in its descent, yet she made no move to finish the job, it wasn't yet time. The face on that pale surface always seemed to stare back at her accusingly, and it made her heart ache whenever she stared back.

After a moment she pulled her eyes away from the moon and set her sights on the small town to the south. The strange sense of unease seemed to grow as she watched Ponyville from her balcony, and she couldn't put her hoof on why that was. She creased her brow in thought, and her frown became a grimace of frustration.

It's only a matter of time now, and yet I'm still here when I should already be down there, waiting for my cue. I know Twilight can handle this, and yet when I think about her, I feel as though something isn't as it should be...

Celestia had laid out all the pieces, now it was up to Twilight to put everything together. She trusted her faithful student like no other pony alive, and still something nagged at her that she'd missed something crucial. The thought was there in the back of her mind, screaming at her to remember, shouting at her that there was an event much worse than the return of her fallen sister on the horizon.

Whispering that it was already too late to stop whatever it was.

The Solar Monarch grit her teeth against the negative thoughts and tried to focus on the moon. She was determined to see what came next through to the end, but then she felt something else. It was like a tug—something pulling her mind away from the task at hoof and towards something altogether different.

Celestia blinked once, then again, then once more, and her eyes widened in shock and confusion. She'd been staring at the pockmarked moon one moment, and in the very next instant, she was sitting in front of her vanity, her own stupefied expression staring back at her in the mirror.

She was still trying to figure out what had just happened when she noticed her image flicker for the briefest of moments. She scrambled to her hooves and took a step back, eyeing the mirror warily. Her eyebrows raised again when she saw that her reflection hadn't moved from where it sat.

Rather, it stared back at her, giving her the same knowing, yet motherly smile Celestia herself might've given a younger Twilight when the filly was asking a particularly troublesome question. It was a smile she'd practiced over many centuries, a smile that hid countless secrets and the answers to many unspoken questions. It also held just the slightest hint of amusement, and that smile, more than anything—more than even the fact that her reflection was alive at all, put the Princess on edge.

"And here we are again," said the reflection with a light chuckle. Celestia gave a small involuntary shiver at the sound of her own voice, but the image seemed either not to notice or care as it spoke, "I'd ask if you've been doing well since the last time I saw you, but it's clear that you have not."

"You imply that we've met before, yet I have no memory of ever speaking to myself in a mirror," her eyes narrowed, "what manner of creature are you?" Celestia asked sharply. Once again, something stirred in her memory, but she ignored it. Another thought came to her mind and her eyes widened. She took a step forward and spoke again, her quiet tone tinged with equal parts hope and disbelief, "wait... is this... a-am I dreaming? Is... is that you, sister? Is this your doing?"

"Sister? What are you..." the reflection replied, raising a quizzical eyebrow. Celestia surmised that the image must've realized something, because its eyes lit up and it gave a sharp, almost mocking laugh, "Oh! Oh no! You poor, deluded sun pony!"

Offended at the reflection's tone, Celestia was about to give an indignant retort, but was cut off by the slow shake of her image's head. It was still chuckling in amusement when it finally answered.

"No, I am not your sister, and this is no dream," it continued, "I could explain the situation to you, but why bother when all I have to do..." the reflection lowered its eyelids and gave an unpleasant smile, "...is drag out what you already know?"

It was like a floodgate had opened up in Celestia's mind. She grunted and raised a hoof to her head as the memories came rushing back to her in a torrent. She had indeed spoken to this creature before, but that fact was immediately shunted aside by the other memory that had been restored.

Her eyes snapped open and she whipped around to face where she knew Ponyville lay. Horror flooded every nerve in her body as she remembered the madness, death, and destruction she'd been far too late to stop. Then there were the ones most likely responsible. Celestia nearly sank to her knees as she recalled the four strange and horrifying creatures that had been her subjects.

It was only then that the distraught Princess realized the creature in her mirror had been right. She'd been an idiot to believe those things in the hospital were still her little ponies. They belonged to who, or whatever this Dead Goddess was, right along with—

"Twilight," Celestia muttered numbly, "oh no. No... nonono... not you, Twilight... anypony but you..."

She continued to mutter and mumble denials as she stared in the direction of the town beyond her walls, unaware that she'd begun clumsily making her way towards the still open doorway leading to the balcony. Her face had grown deathly pale and her eyes wide and unfocused with fear.

With these memories came far more questions than answers, but in that moment, all Celestia could focus on was the image of Twilight Sparkle sprawled out amongst the rubble, the sickening aura she'd felt from the lavender unicorn, and what the reflection had revealed to her about the fate of her beloved student.

"Ah, I wouldn't go gallivanting off like that so soon," came Celestia's own voice from behind her, "I didn't restore what you've lost just so you could go and get yourself killed you know."

Celestia had made it halfway across the room before she realized she'd been moving at all. At the sound of her own voice, she froze and rounded on the mirror, sudden fury snapping her out of her stupor and her eyes blazing like miniature suns. The temperature of the room noticeably increased, but the reflection stood calm and unaffected.

"What do you know of it, creature?!" she hissed, turning and stomping towards the mirror, "you told me many things but I still know little to nothing of what happened to my ponies! To Twilight!" her eyes narrowed and her horn flashed gold. For a brief moment, the walls lit up with her aura and all noise beyond her chamber fell away. With the silencing spell in place, she continued speaking, her voice growing cold, "if you're here to help me, then tell me what in Tartarus is happening in my kingdom."

"Well, that was unexpected," the reflection chuckled, "I was hoping for a different reaction, but it seems we're going this route instead. How... interesting..."

Celestia eyed her grinning reflection with no small amount of suspicion. The memories churned unpleasantly in her mind, and she could feel fear and despair threatening to overwhelm her, but she ground her teeth, pushed it back and forced herself to think rationally.

Whatever this thing in her mirror was, it had the same oppressive and repulsive aura as the mares in the hospital. It made her sick to her stomach, it made her shiver in fear and disgust, and, perhaps most importantly, it had access to powers she didn't understand. For all Celestia knew, it could've planted false memories in her mind to scare and confuse her, such magic did exist—she'd seen it at work firsthoof in the past.

She cast her mind back, setting aside the memories she'd gained from the creature and looking over everything she'd done prior to current events. Her horn flared to life again and a warm golden glow washed over her body as she cast another spell, this one to detect any mental or physical tampering that might've occurred by way of magic.

She wasn't too surprised when her scan turned up nothing—if anything, it only put her that much more on edge. The reflection was silent as it looked on in amusement, somewhat to the annoyance of the Solar Princess. She swept the petty irritation aside however and focused on how to get the most information out of the creature as quickly as possible.

The only problem is that I can't trust anything it says.

"Quite a conundrum, isn't it?" the reflection finally spoke, "you want answers, and I can give them to you, but if you're unwilling to trust even your own memories, how can you trust anything I say? Yes, it certainly is an incredibly frustrating situation," the image frowned, "...for both of us."

That was one thing they could both agree on.

There were all manner of spells that would render the problem a complete non-issue, and Celestia knew many of them, but the vast majority of those spells required the untrustworthy individual in question to be physically present, and Celestia had the distinct feeling the other spells would've been terribly insufficient.

All of what I know affects, and is affected by magic, and I'm fairly sure I'm not dealing with magic here—at least, no magic that I've ever heard of. If the Elements were still active I might've been able to make some headway, but...

"Time grows short, and my subjects will soon face threats both known and unknown," Celestia finally said, deciding on a course of action, "perhaps a show of solidarity is in order."

"A show of solidarity," the reflection replied flatly, "and what did you have in mind, princess?"

"Well, to begin with, why don't you show me what you really are beneath that facade?" Celestia suggested, "then we can go from there. It's clear that you want something from me, and I have no doubt that you could simply take it if you wanted to, but you haven't.

"Instead you choose to communicate with me, but you have yet to do so honestly," Celestia raised a hoof to her chest, ignoring the slight tremor that had yet to abate, "all I seek is answers for what's happening to my subjects, but with how you've approached me, there's no possible way for me to trust anything you say."

Her mirror image frowned.

"I understand where you're coming from, Princess, really, I do," it replied, "but this is not a path you want to travel, believe me. You have lived a long time, and admittedly, you are wise not to trust me, but surely you are aware that some things are... best kept in the dark?"

"I'm well aware," Celestia answered with a nod, "but without some kind of earnest gesture on your part, I can only see this situation as suspicious and opportunistic, given what is soon to come," she snorted, "for sun's sake, you haven't even given me a name, how am I expected to trust you?"

She gave the reflection a level stare, and it stared back silently, its expression impossible to read, even to Celestia's trained eye. Hopeful that she was gaining some ground, the Princess continued on, all the while aware that the hour was drawing nearer and nearer.

"I've been in these kinds of situations before, creature, and experience tells me that you are looking to make some sort of deal, am I wrong?"

The reflection remained silent for a long moment before letting out a weary sigh.

"No, you are very much correct," it conceded, "but I see now that it would be a waste of time to give you the details of my offer," the mirror image smiled humorlessly, "you are a much stronger being than I gave you credit for," the smile vanished, "...and that is a problem."

Celestia gave a frown to match that of her reflection.

"...come again?"

"The dead goddess does exist, and is a very real threat to your world," the creature continued, its magenta eyes fixed on Celestia, "you at least know this much, yes?"

"If what I heard from those mares in the hospital is to be believed, then yes," Celestia replied carefully, "at the very least, I know there is something amiss besides my sister's inevitable return, but that doesn't necessarily lend credence to your own words."

"True, but if you believe anything, then believe this, Sun Princess," the voice of the mirror image grew cold, far colder than even her own tone had been earlier, "she is very near, and it is only a matter of time before she brings ruin to everything you've built, and that would be just the beginning.

"I meant to help you, to offer my assistance in ridding your dimension of her and her ilk, but I, as a Black Dimensional being, cannot survive in your dimension without a host, and you are the only White Dimensional being I could find with the mental fortitude to keep me contained without breaking apart or going mad in the process."

"Out of the question," Celestia answered immediately, "I know nothing of White or Black Dimensions, but I know all too well what becomes of ponies who give up their body, mind, and soul to something they know nothing about, and more often than not, terrible sacrifices are made to fulfill the desire of the one that made the offer."

"And therein lies the problem," the reflection replied with a nod, "it's clear that we cannot reconcile our differences, and that you will not trust what I say. Your need to know more about me, while understandable, poses certain issues I'd rather you not have to face... but there it is. We're getting nowhere like this, and as you said, time grows ever shorter."

"What do you propose then?" Celestia inquired, wary and uncertain of what would happen next, "will you reveal yourself to me so that we might talk openly and honestly?"

Silence was the only response she received for several long moments, as the reflection stared at her with that same, impossibly blank expression, and then...

"Suppose I'm right about everything, and that your memories aren't a lie," the creature said, its tone suddenly flat and unsettling, "suppose your precious student is indeed host to the dead goddess. Tell me, Princess, what exactly would you do then?"

Celestia blinked.

"I..."

The question completely caught her off gaurd. She'd been so focused on finding out the creature's true intentions that she hadn't given any thought to the possibility that what it said and what it showed her might just be true. She'd been quick to deny the thing outright simply based off of what she felt from it, and hadn't thought at all about what she'd do if it was right.

She'd gotten so caught up in trying to reason with the thing before her that she'd completely overlooked the simplest solution. Only now did she realize that just checking on Twilight would've proven whether or not the creature's words rang true. The thing in the reflection gave a grim smile at the realization on Celestia's face.

"Would you confront Twilight Sparkle?" the creature pressed, "would you try to talk to her? What if she no longer recognized you? What if she'd been fully taken over by the goddess? Would you fight against her? Try to kill her if it came down to it? Could you even bring yourself to do such a thing?"

"What? No, I..." Celestia hesitated, caught on the backhoof, and unsure of how to respond, "I..."

Brief images of a desperate battle from long ago flashed across her mind. Swirling colors, an expression of shock and outrage, and the pale moon filled her vision. In her mind's eye, Celestia saw the moon's surface, once bright and flawless, become stained with the blemish of both her and her sister's folly.

Could I bring myself to do what needed to be done if it came to it? I did so once before, but could I do it again?

Celestia had no idea, and had the feeling she wouldn't know until the situation was staring her in the face. She knew she wouldn't be able to outright kill the pony who'd been like a daughter to her, but if needs must... if there was another way...

I need to get out of here, away from this thing. I need to see Twilight, find out for myself what's going on.

Praying that what the creature said about not being able to cross over into her world was true, Celestia's horn flashed for the third time that night. She'd intended to teleport out of the room and make her way to Ponyville. She felt the tingle of magic wrap around her, she felt the instantaneous compression and displacement of air that signified a successful teleport, she blinked and stared dumbfounded at the mirror in front of her.

She hadn't moved an inch from where she stood before.

"No," she whispered, her eyes slowly widening in horror as she grasped the gravity of her situation, "it was a lie then. You've made your way into this room, into this world, haven't you?"

"In a manner of speaking," the reflection replied with that small, knowing smile, "I didn't want to have to reveal this, at least not yet, but I'm already in your head, princess—well, to a certain extent. That's part of the reason why we can communicate like this."

"I don't understand," Celestia muttered, backing away from the mirror a step, "how... when did you..." her eyebrows furrowed in realization, "the balcony. Something happened between when I was out on the balcony and when I appeared before the vanity."

The thing in the mirror merely gave another weary sigh in response.

"This isn't how things were supposed to go," the mirror image replied, almost in a tone of lament, "I saw a very different outcome, but fate, it seems, is a fickle thing," it chuckled humorlessly, "it's frustrating, but there are things even I can't control," the reflection shook its head, and gave the Princess a cold stare, "then again, perhaps this is for the best."

The bemused frown Celestia wore at the creature's words gave way to an uneasy grimace. Something in that look caused Celestia to flinch, but she held her reflection's cold gaze. A knot of dread began to form in her stomach, but as with her prior fear, she held it at bay.

"This would have been much easier on you if you'd accepted me as I am, without asking questions. We could've helped each other," the creature continued with a deadly calm, "but now we've reached an impasse and there is no more time left. I am patient... so very patient, but the time has come for action."

Celestia gasped as she felt something in the air shift ominously. A chill shot down her spine and she shivered involuntarily.

"You wanted a show of solidarity?" the reflection asked, its voice taking on a strange, almost guttural undertone that made Celestia's head throb painfully, "you want answers? You want to know of my true nature? To see what manner of creature I truly am?"

The painful throb in her head became a horrible pounding that resonated with the sudden pounding of her heart as Celestia watched the pristine alicorn form in the mirror twist and warp, the reflected surroundings changing right along with it. Then the mirror itself began to expand outward, or so it looked that way to Celestia.

She found herself unable to look away as the creature in the mirror became less and less equine and more monstrous. She tried to close her eyes, tried to turn away, tried to do anything, but she could no longer move—she could scarcely even breathe. Then, all at once, what little light there was around her vanished, bathing her in complete darkness.

The room was gone, the mirror was gone, there was nothing left save the darkness.

For a moment, Celestia thought she'd gone blind, then she saw something in that darkness—some kind of movement. Celestia opened her mouth to say something, or perhaps let out a horrified scream, but her breath caught in her throat and she could only give a choked gurgle as something cold and slimy wrapped tightly around her neck.

YOU KNOW NOT... WHAT YOU ASK FOR... FOOLISH MONARCH... BUT VERY WELL... I WILL ENLIGHTEN YOU...

She could hear it now as she was dragged forward, the horrendous sloshing and squelching of some massive fleshy thing hidden in the darkness. She reached for her magic in a half-hearted attempt to fight back or escape, but her horn didn't even flicker.

Then she saw it, and all thoughts of fighting her way out of this nightmare fled from her mind. She wanted to scream, but she couldn't. She couldn't scream, she couldn't think, she could do nothing but stare in numb disbelief at the mountain sized impossibility before her.

I AM HE WHO WATCHES... I AM HE WHO WAITS... I AM THE MOST ANCIENT OF KINGS... I AM... NEL-BALOTH. THE TIME FOR WORDS... IS AT AN END, PRINCESS... AND NOW I WILL SIMPLY TAKE... WHAT I REQUIRE...

The slimy limb squeezed tighter around Celestia's throat and pulled her closer, but by that point, her once sharp mind had already been reduced to nothing, save for a single image of a smiling lavender filly. She held onto that image for as long as she could until that too faded away. Everything she was and everything she knew had disappeared, replaced by blinding, spinning motes of light in a world of black.

Somewhere far, far away, in a distant sky, a certain set of stars vanished, and with them, the pockmarked image that had adorned the moon's pale surface for so many years.