The Gala had ended in chaos. Luna had missed the whole thing. She wandered out into the garden, which looked as if a small tornado had hit it. A tiny stab of the old familiar feelings cut into her. She'd been locked into her nighttime duties, overseeing the dreams of ponykind and banishing the nightmares that seemed specifically likely to either be caused by dark entities, or that would allow such entities to feed. She hadn't had time to enjoy a gala, because they weren't held at dawn, when she would be free to step down from her duties. And no one had thought to come to her and tell her what was happening, and they probably wouldn't have even if she hadn't been meditating and traveling in dreams—
--no. No, she recognized the thought pattern, and quashed it. Time to tell the truth to herself. She'd always hated these sorts of parties. Well, not always – when she was little, they'd been great fun, to run around in a pretty new dress and then get shuffled off to the kitchen with Moon Cake the cook (and later, Discord, but that hurt to remember) to eat all the delectables that had been made for the banquet but had something visually wrong with them, so they hadn't been deemed acceptable for noble guests. Celestia could do the hard work of playing Crown Princess and saying hello and trying to remember everypony's names; Luna would gorge herself on snacks and tell Moon Cake all about the wild adventures she had had in dreams with her stuffed animals. And when Celestia had been Ruling Princess and Luna had been her heir, parties had been about shyly giggling as colts who thought they could marry into the royal family had flirted with her, and occasionally helping Discord pull off a ridiculous prank or two.
After Discord's death, after Chaos Incarnate had risen up wearing his face, there had been no parties for centuries. Not fancy royal parties, anyway, and the only ones she'd attended that the thing claiming to be Discord had thrown were the ones he'd forcibly teleported her into and then wouldn't let her leave. By the time they'd overthrown Discord, she was an experienced mare, not a giggling filly, wise in the ways of espionage and war and dreams and magic.
But not in attending parties.
There'd been no Grand Galloping Galas back then, and no one but nobility had ever been invited, but there had been many more of them as Celestia tried to knit the land back into solidarity after so long being separated by chaos. In those days, the fact that she ruled the night had made her the hostess, the Princess who would smile and nod and greet all the guests, while Celestia would circulate and work the crowd. It had been boring. Mind-numbingly boring, and she'd gotten a reputation for being aloof and cold just because she couldn't remember anypony's names and would thus just greet them with a nod and rote words of welcome, while Celestia remembered everypony's names even if she'd only met them once for five minutes, and what Celestia was doing seemed a lot more fun than what Luna was doing until she tried to do it and the anxiety set in – what if she was doing it wrong? What if she gave offense? Did they even want her here? They always seemed so friendly and open with Celestia, but with Luna the nobles were stiff and correct and it was horribly awkward and she always wanted to run away.
So she had. Declared that her role in protecting the dreams of ponykind was too important to set aside for a party. It was even true. Chaos had torn holes in the thaumosphere everywhere, and the Spirit of Disharmony had willingly thrown himself into battles with the things that invaded, because he thought it was fun and he didn't want to share his toys, not because he'd actually cared if ponies went insane because dark creatures from beyond fed on their dreams. Luna and Celestia couldn't repair the thaumosphere quickly, even with the Elements; they had to identify breach points before they could close them, and while they could easily sense a breach point once they were close to it, or if they knew generally where it was, they couldn't simply scry for them all. So Luna had to protect ponykind's dreams.
Some nightmares were necessary for the pony who had them to work through some kind of trauma on their own, or as a wake-up call. Others were either caused by the Shadows from Beyond, or were a source of food for those entities, a dark thing growing fat and bloated as it slowly consumed a pony's mind until nothing was left but paranoia and terror and disordered thoughts. Those nightmares had to be stopped, and anything within the pony's mind banished. Other nightmares were repetitive, night after night a pony's mind trying to teach the same lesson to the waking self, and Luna could banish those by helping the pony work out what the point of the dream was, while they were still dreaming it.
But when she'd removed herself from the galas, then hardly anypony ever saw her at all, unless they were palace staff. No one came to Night Court, despite the fact that it took far, far longer to see Celestia, because Luna had a reputation for being stern and cold. Just because Celestia was willing to be endlessly patient with idiots and tolerate their stupid disputes as if they actually meant something. Arguing over a strip of land a head wide and three barrels long! So they hadn't come, and she'd stopped holding Night Court, spending all her time overseeing dreams. At least there, her little ponies respected and loved her for banishing their nightmares.
And then she and Celestia had finished sealing the thaumosphere, and there was no longer a good reason to protect ponies from dreams, or at least not to do it as often as she did it. But Celestia had already taken over all the burdens of administration, and the things she had prepared herself to do – the things she and Discord had vowed to do for Celestia, to keep the Ruling Princess's hooves clean – were no longer needed. There were no wars. (She'd almost looked forward to the battle with Sombra; it had been the first time she'd been able to throw herself into a battle in decades.) There was no one to spy on. There were no dirty deeds that needed to be done by dark of night to protect Equestria. Luna had been Celestia's heir in theory, before losing Discord, before the chaos, but she'd never really trained to do Celestia's job, and she didn't want it. Smile and nod? Make endless pointless small talk with nopony she cared about, when she could be reading, or experimenting with magic, or studying the True Stars with her magically enhanced telescope, or protecting ponies' dreams? How could Celestia even stand it?
She'd felt useless. And she'd felt left out. And she'd been angry, because it was her own fault that she'd never trained to be a princess in peacetime, but surely it wasn't her fault that ponies ignored her just because she wasn't the princess they saw in the day. And she'd studied, tried so hard to learn what she needed to rule a nation, important things like civil engineering and farming practices and jurisprudence, and she'd brought her ideas to council meetings with Celestia and the nobility and everypony had ignored her. Because they were used to her knowing nothing about the topics that were important to the day, and they weren't willing to give her a chance. Because Celestia was there, and when the sun was shining, who could see the moon?
Luna closed her eyes. So easy to see, in retrospect, how it had been all her fault. How she'd retreated from ponies and then blamed them for the fact that they no longer knew her. Celestia blamed herself, but Celestia was wrong.
Celestia also thought Nightmare Moon was someone else.
If Luna felt left out or sad because she hadn't had a chance to attend the Gala, when she hadn't even wanted to and she'd always hated such parties before and she'd been the one to insist that the dreams were more important... well then. She deserved it. She'd brought all of it on herself.
Luna's walk brought her to the place she had always been heading toward. Chaos had erupted all over this garden last night. Time to face something she had been trying to avoid for the past year.
"Celestia says thou art my brother-in-law. Art thou?"
"Mmm... in truth, no. See thou, it's that troublesome matter of 'in-law'. That is for ponies who marry, and them alone."
"But art thou not to marry Celestia someday?"
Laughter. "Oh no no no. No. Not me. Not marriage. Nay."
"Why not? If thou lovst her—"
"I could say, because she is the Crown Princess and 'tis her duty to marry one who might be king someday, not for love. She must marry for 'political advantage'." He used a single digit on each of his paws to make air quotes.
Luna made a face. "Ugh. Glad I am that I'm not the Crown Princess!"
"I agree completely. But even if she was allowed to marry me, we would not."
"Why not?"
"Because love doth not need marriage. Marriage is a matter of society saying 'well and good then, 'tis acceptable for you two to love each other! We approve! Do go on!' But whyever should anypony care what society thinks? Love is the most chaotic of emotions; why must we tie it down with law? Why do Celestia and I need some sanctimonious unicorn – or your father, for that matter – to tell us that 'tis allowed for us to love each other? What, need we to ask society's permission? No. I reject that. Love is personal, 'tis individual, and Equestria has no business with it."
"So thou'rt not my brother-in-law?"
"Only in wise that the in-law part is incorrect." He ruffled her mane. "But if we said brother-in-heart, then that would be correct. But 'tis such a mouthful to say, so why not just 'brother?'"
"But then wouldst that not that make thee Celestia's brother too?"
"Nay. If marrying someone makes their sister into your sister in the eyes of the law, then loving someone and wishing to spend the rest of your life with them makes their sister your sister in the eyes of the heart. See thou?" He cast an illusion spell, making a red heart-shape with eyeballs appear. Inside the eyeballs there were smaller heart shapes. Luna giggled. "Anyhap, I do muchly need a sister. If thou please?"
She blinked at him. "Why needst thou a sister?"
"Because I am a draconequus, and a boy. Draconequus boys must needs have sisters."
Luna knew that the word 'boy' meant 'colt' in other species, so that didn't confuse her, but she didn't remember the appropriate female counterpart. "So do draconequus fillies need brothers?"
"No, because they're girls. A family is a mother, her foals, and her brothers. Boys who lack sisters don't in truth have family."
She pouted at him. "And what of fathers, then?"
"Draconequui don't have fathers."
"Yes they do! I learned it from Governess Slate. All creatures need have a mommy and a daddy unless they make clones of themselves and if should they do that, then they haven't colts and fillies, but just one kind. You're a colt, so you must have a father!"
He shrugged. "'Tis certain I did, but he mattered none. My point is, I must have a sister or I have no family at all. And Celestia cannot be my sister because how oddsome that would be. So I'm afraid it must be thee. And if thou'rt my sister then must I be your brother."
Luna nodded regally, as a princess should. "Very well, I accept this. Thou canst be my brother. Which means in truth brother-in-heart but we don't say the last part because it's too long, 'tis so?"
"Exactly!"
She lit her horn. When he'd been free his mind had always been warded against her, but after they'd sealed him in stone, he'd let her in any time she wanted to enter his dreams. Which she usually hadn't, but he could enter hers if he felt like it, because he could dreamwalk himself. (Because she'd taught him. No, she'd taught Discord. This was the Spirit of Chaos. The same monster her mother had died fighting, reborn in her brother's body.
Was that even true anymore?
Had it ever been?)
This time, his mind was warded as strongly as it had been when he'd been free. Surprising. He'd opened his mind to her because he'd been lonely (could a monster be lonely, she'd wondered? She knew the answer to that now.) Was he no longer lonely? Or after she'd been on the moon for a thousand years, had he hardened to the outside world, no longer expecting or even desiring contact?
She'd never told Celestia he was alive in there. Her heart was so soft. Celestia had always believed this was the real Discord... and centuries before, Luna and the real Discord had pledged to make the hard choices, the ones that were dark or immoral or maybe even evil, and keep them from Celestia, so she could stay pure. That had mostly fallen apart after centuries of fighting Chaos, and the Celestia after this creature was in stone had been so much harder and tougher and much more stained than she'd been in childhood. But she'd still held off on telling Celestia what she knew. Celestia suffered enough grief from having turned him to stone. To know that he was alive in there and lucid dreaming – or, according to what he'd told her at the time, frequently awake – would have horrified her, because she believed he was the real Discord.
Luna, of course, knew better. Her brother could never have become the monster the Spirit of Chaos was. Even if he had all of Discord's memories, and claimed to be Discord. Even if he thought he was Discord. Maybe Celestia had forgotten, but Luna never had. Their mother, Queen Imbrium – the mother Luna had never known, who flew off to die protecting Equestria when Luna was four months old, the mother everyone had always said Luna took after – had fallen in battle against the Spirit of Chaos. The same thing that the creature wearing Discord's face said it was.
But all of her certainty had come before Nightmare Moon.
It was funny. Celestia had been convinced that Discord was really Discord. But she was also convinced that Nightmare Moon wasn't Luna. And Luna had found it convenient never to tell her the truth. When the Elements of Harmony had washed over her, ripping away so much of her magic that she'd solidified from her magical form into the shape of a filly, and all the dark thoughts and rage and jealousy that had comprised Nightmare Moon had been torn away, she'd felt as if Nightmare Moon was someone else. Luna couldn't have done any of those things! Luna couldn't imagine why she would ever have wanted to!
But the memories came trickling back.
When she'd found ponies who were being devoured inside by the Nightmare Forces, it was never possession. It wasn't even mind control. It was more like what Discord did, bringing darker traits to the foreground... except it was worse. The happiness, the love that the victims felt was being swallowed, drowned in darkness, and their thoughts were a tangled, writhing mass of paranoia. Everypony is trying to kill you, including your spouse and your foals. Nopony really loves or cares about you, they just want your money. You will never find a mare who'll love you, so you should just go kill a bunch of mares with spells to punish them for refusing to give you love. She'd seen it so many times, when the thaumosphere was so raw that the creatures were coming through all the time and she couldn't possibly get to them all before they got a hold on a pony. It was still the same pony, but infected with obsessive dark thoughts, thoughts they'd had before the infestation but that had been balanced against happier, more harmonic thoughts as well. There was no separate pony there, and when she lanced the boils in the mind and banished the darkness, she wasn't getting rid of a personality. The dark thoughts would still be there afterward, but at a normal level, much, much lower, nowhere near the ability to drown happiness.
She was the expert. Celestia hadn't seen it happening and still didn't understand what it was because Celestia hadn't spent a century or two fighting them, freeing other ponies from them. The Nightmare Forces, the Shadows, the Cold Ones – they weren't minds. Or if they were, such minds had never revealed themselves to Luna. They were collections of negative emotion, intelligent enough to figure out how to infect their host, but the host didn't become a different pony. The Nightmare Forces worked with what was already there, amplifying it to unreason.
She had been Nightmare Moon. She had really plotted to kill her own sister and bring eternal night. She had really thrown obstacles in the way of mares who were trying to stop her, innocent civilians that she could have killed, and the only reason she hadn't tried harder to kill them was that it turned out monsters could be lonely. After a thousand years, she'd still hated ponies for their refusal to love her – but she'd been so hungry for something, their respect if she couldn't get love, their fear even, that she couldn't bring herself to kill. Terrify, yes. She'd wanted those mares groveling at her hooves. Not dead.
And now that Harmony had lanced that boil in her own mind – now that the darkness had drained away, and she was consumed with guilt when she remembered what she had done—
"Is it you?" she whispered to the statue. "Was Celestia right? Was it you all along?"
What if Chaos was like the Nightmare Forces? It was obvious to her that Discord hadn't succumbed to a Nightmare like she had. He hadn't been paranoid, fearful, angry, aggressive. Not most of the time, anyway. He had just not cared about anything except getting his fix of chaos. Remaking the world according to his whim, again, and again, and again. He had laughed constantly, taken nothing seriously, and made the world a miserable place where nothing was stable – unless somepony crossed him and actually managed to offend or hurt him, in which case he dished out disproportionate punishments in sudden rages, and then just as suddenly would calm down once he'd done it and return to his usual giddy clownishness.
He was alive in there. Trapped, as she'd been in the Moon. Worse, even, in many ways. Nightmare Moon had been converted to magic and bound within the moon the way Discord was bound in this stone, but Nightmare Moon had been in her place of power, with more than enough magic to make an avatar for herself, a magical construct containing her consciousness that could walk the surface of the Moon, and gaze up at the Earth in rage (and grief, so much grief for what she'd lost, but she could never bring herself to admit that). Discord couldn't go anywhere. He could walk in dreams, for whatever that was worth, but he couldn't interact with them and he'd have no sense of physical movement, as she had when she'd made her magical body stalk the Moon's surface. And he'd been trapped in there for a few centuries before Luna had been sent to the Moon.
What if he wasn't a monstrous creature that killed her mother and then wore her brother's identity like a skinsuit? What if he was, in fact, really Discord, fallen to Chaos in the same way as she had fallen to Nightmare? What if she and Celestia had trapped, not an eldritch abomination impersonating her brother, but her actual brother, in stone, for more than a thousand years? And when she'd had the power to say something, to tell Celestia he was alive and aware in there, she hadn't done it?
"Thou must have taken great joy in tonight's events," she said softly, slipping back into the language she was more comfortable with. "All that chaos, and made by the Bearers of the Elements of Harmony, no less. That's an irony methinks thou couldst well appreciate."
The first time the Elements of Harmony had hit her, all she'd felt was rage and pain – more existential pain than physical, as she'd been forcibly converted to magic and torn from the world. And she'd been so lonely, so horribly lonely, all those years. There had been so many moments when the parts of her she thought of as her true self had temporarily come ascendant, when she'd wanted to weep for the loss of her sister and her world, but always the rage had come back, because it was Celestia's fault she was here, Celestia's fault and the fault of the damned sun-loving ponies who refused to appreciate her. She'd carried her rage and jealousy for a thousand years. But there had been so many moments, lonely in her prison, where if Celestia had appeared right then and offered her hoof... Nightmare Moon might have taken it. Might have faded back into Luna of her own choice.
Was it possible that Discord was really Discord? Was it possible that more than a thousand years of loneliness might make him willing to change his ways? Or could the Elements of Harmony purge the madness from him, as they had for her the second time, rather than turning him to stone?
(But Discord had always feared the Elements of Harmony. When they'd first found the Tree, she and Celestia had been captivated, but Discord had been so terrified he'd used his superior physical strength, not even his magic, to grab the two of them and drag them away. And Harmony and Chaos were opposites, weren't they?)
"I wonder," she said, "whom thou art. Celestia had always such certainty that my brother lived on behind thy eyes, and thou thyself said as much. I thought, 'twas impossible for my brother to become such a monster as thou didst..." She bowed her head. "But then I my own self tried to kill Celestia. I would have brought eternal night. Can I truly judge thee?"
The statue was silent, but she felt something shift within. Abruptly she knew she was being watched. Well, not literally. Sound vibrated through stone, but light couldn't pass through granite eyelids. In his prison, Discord could only hear. Still. He was paying attention.
How Celestia could never have noticed this, Luna couldn't imagine. She controlled a shiver, even though Discord couldn't see it. Luna wasn't casting dream magic right now. There was no reason she should be able to feel the pressure of Discord's blind stare, the focus of his mind, unless enough of his magic was leaking out of his prison that she could feel the shift. Or unless her time on the moon had made her abnormally sensitive. Which she supposed could easily be it.
She took a breath. "I will speak with Celestia," she said. "Perhaps... perhaps if what now I suspect is true... mayhap thou mayst be ready to let go the madness of Chaos, to end the loneliness. If thou art in truth still my brother..."
Surely if the real Discord was in there, the loneliness would have affected him as it had her? Discord was an extrovert, unlike Luna, and loved attention; surely the loneliness would have been worse for him. If he truly was who he claimed to be, and not a monstrous dybbuk raised in her brother's place. If there was something of a pony – well, of a mortal, fleshly sapient being anyway – inside him, if he was truly a thing that could feel loneliness. If he was truly a thing that could set aside chaos for the sake of family or friendship, and not a creature for whom chaos was the only reality.
"I know not if this is the right choice," she said softly, looking up at the statue's sightless eyes. "But I will tell Celestia, at last, that thou still livest and thinkest within there. If I know my sister's heart... something will change." She couldn't bear to make him promises, or offers, or even outright speak the words that he might be set free, because if Celestia didn't agree, Luna doubted she would push. Celestia was the one who thought Discord was truly Discord. If she didn't agree that the right thing to do was to find a way to release him, once she knew he was aware... so be it.
But she knew Celestia. She doubted that that would be the case.
She bowed her head again, and then trotted away. Celestia would be sleeping by now; it was only a few hours until dawn. In fact, she was up late enough tonight that perhaps Luna would take her duties this coming morning, and let her sleep in a bit. Most likely she wouldn't see Celestia until tomorrow night. Well, Discord had waited over a thousand years; he could wait another night.
The moon was clear and bright, and Luna's night vision was keen. But she had been probing the statue magically, not studying it physically, and it was her first time truly seeing it in more than a thousand years.
So she didn't notice any of the hairline cracks in the granite.
Author's Note
In my headcanon, Luna's speech when she slips up and goes archaic is an actual reflection of the way they used to talk (including Discord), but when writing stuff from the perspective of Celestia or Discord, it's way too much work to render flashbacks that way. When I'm in Luna's POV and I'm writing a flashback, though, I'll generally go for the archaic language. She hasn't had a thousand years to forget how she actually talked then.
Timeline-wise, others have also noted that the first Grand Galloping Gala, held on Canterlot grounds and in the garden, generated far, far more chaos than one fight between fillies, and that Return of Harmony is the very next episode. I believe it was the fight (which itself was provoked by Discord's magic leaking) that gave him the last little push he needed to break free, but I believe the chaos the girls caused at the Gala did a lot more damage to his prison, so that all he needed was a tiny push.
