A collective gasp ripples through the crowd as nopony says a word. Something opens itself up to Twilight: there is nothing anypony in this room can do against an Alicorn princess, if she means them ill. Twilight is by certain metrics one of the most developed mages in Equestria, or at least one of the most studied, but she has no combat training whatsoever, and she has no hope in Ponyville having a single proficient combat mage. She has never fought anypony before, and almost never hurt anypony. And even that time, she had help.

"Tell me, my little ponies," Luna spits, in open mockery of her sister. "Does any of you know who I am?

Twilight knows, of course. In that moment, it feels like the only thing she's ever known: On the longest day of the thousandth year, the stars will aid her escape, and she will bring about nighttime eternal. But there's no point in singling herself out in the dark horse's attention. And anyway, her mind is saturated in frantic thoughts of escape; a desperate battle between fight and flight instincts is raging, and fight is being expediently routed.

"Not a single pony? Not one of you foals has heeded the prophecy of my return?"

Twilight has enough magic capacity for exactly one medium-range teleport, with roughly a twenty-two-second charge time. There's no way she's going to get away with a glowing horn for that long, or probably even a full second. If she can find something to get behind—

"I," screams the umbral god, "am Nightmare Moon." Her voice booms with an unreal authority. An ice-blue shimmer sparks at the end of her horn as she speaks the words.

...Huh? She's going by a different name?

"You may know me from your history books and old pony's tales as Princess Luna. But that princess of the old kingdom is dead."

Can an Alicorn sense ambient magic? Twilight fears hiding her horn's glow underneath a tablecloth, but being obliterated in a split second anyway. It's entirely possible that putting off checking out that Alicorn reference guide would become a fatal mistake. Twilight Sparkle, a pony who lives more in the written word than in reality, destroyed by reading the wrong books. Has Celestia ever sensed my magic from far away? She runs over whatever memories of Celestia come to her desperate mind... yes, in fact, just once. At her entrance exam. But that was sort of an exceptional circumstance...

"One thousand years ago, I was banished to the moon by my sister for beckoning the glory of eternal night. But tonight, I have escaped my lunar prison. I will reign forevermore, and the sun will never rise again!

As a suffocating sense of doom pervades her mind, Twilight's powerlessness pushes down upon her. There is exactly one pony in the kingdom who could hope to protest if Nightmare Moon decides to start murdering. Where is she?

"Princess Celestia is Princess no more! She has been vanquished by my cursed hooves! Run, my little ponies! Spread the word across the world of my return! Train your soldiers, mount your forces! Depose me if your meager hooves are able; the bearer of the Elements of Harmony welcomes all challengers!"

Twilight screams internally before the words are even fully processed. The... bearer? Something black unfurls within her, and her heart starts to mourn Celestia, until she can't feel it beat. Her hooves fail her, and she piles upon the ground.

"Your eschaton begins at this very moment! Savor your dying memories of the sun!"

Nightmare Moon's gangly forehooves each stomp onto the wooden planks in turn, and a crystalline blue shockwave ripples across the stage, shattering it end to end. At the same instant, every candle in the hall is snuffed without a sound. Four helical beams spray from her swirled horn and crash into the top corners of the room, dislodging chunks of rafters and stone. Ponies start screaming and scrambling for their lives as she looks on and laughs a laugh that sounds like something feral dying in an earthquake.

And then Nightmare Moon is gone, stepping through the same starry mist by which she arrived.

Twilight, unmoving, exhales, and her horn begins charging.

Twilight materializes directly in front of Spike's bed, sees it, screams, and gallops downstairs and out the door.

The streets near her library are eerily empty. How could I be so stupid? So bucking selfish?! After a few streets, she passes the fastest runners, mostly stallions, each giving her a look of utter confusion and pity. Maybe some of them who witnessed her earlier breakdown think she's amnesic right now, or in a fugue, running towards some deluded end, but nopony stops to turn her around. I need you to be okay. You have to be okay. The crowd thickens as she draws closer; by the time she's within a few streets of town hall, she's pushing through hundreds of hysterical ponies stampeding away.

But within the ruined starlit hall itself, there's nopony, excepting a purple dragon who is very alive and wandering around the stage. He runs over to her and takes her forehoof in a hug. "Twilight! I finally found you!"

"Spike! I'm so sorry! I teleported away as soon as she disappeared. I didn't even... I didn't even look for you! I didn't even remember! I'm so sorry! I'm so sorry, Spike!" Twenty-two inexcusable seconds I spent cowering with my eyes closed, thinking about the Princess.

Teardrops are falling on his green scales and purple head. He shivers and pulls away. "Shhh. Everything's fine, Twi. Princess Luna—I mean, Nightmare Moon is gone. This is just an empty room now. Are you okay?"

"Everything's fine? Everything's fine?! Ponydom faces certain extinction and everything's fine?"

Spike lowers his eyes and mutters, "You know what I mean, Twilight. I... I just mean... if you weren't okay, I..."

Twilight reins in her breathing and sits down on the cold burgundy carpet. "...I know. I'm safe, I'm fine... just out of breath and out of magic. Wait... that's weird. I'm fine. How am I even still conscious right now?"

"I don't know, but don't complain!" Gently, his mouth curls up. "This is not a bad time to still have your wits about you. What should we do?"

"That's the question of the millennium, Spike." She sighs. What should we do? There are more problems coming than there are stars in the sky. But to Twilight, right now, they feel just as distant. There's only one thing her tiny pony brain can imagine doing.

"I... I need to send a letter to Celestia." Spike's mouth opens a crack, but nothing comes out. "I know. Spike, I know. But I have to try. Just in case. I... I have to. I guess... let's just go home." She's unsure whether she holds a single shred of hope of successful delivery or whether her mind just needs a low-effort task to occupy itself, but either way, it's the only plan she has the willpower to think of.

Spike nabs a cold apple fritter from the catering table before scampering to catch the Twilight trotting away. This time, she walks, gaining and losing composure in bursts along the way.

When Twilight and Spike round the corner to the library, they see a white unicorn poised outside, seemingly scanning the empty streets.

"Rarity!" exclaims Spike, bee-lining towards her. "You're okay!"

"My stars, I'm so relieved to see you both again! Twilight, Spike, dearests, the girls are inside debating what to do about you two being missing. Come, come, ease their hearts!"

More ponies in my house, really? "And what, exactly, are you doing alone outside?"

"Well, the last time you entered your home to find a crowd of ponies you didn't expect, darling..."

"...Gotcha. Let's go inside. It's chilly." And it will only get colder, until we can't go outside without insulated clothing, until every tree in Sweet Apple Acres withers away, until... Twilight shakes her head as if to dislodge something, and follows Rarity's lead through the door.

Inside, she sees Fluttershy, Applejack, Rainbow Dash, Tinder Heart, and a distant Pinkie Pie idly sitting in a corner. She has no doubt the mare came to force more friendship down her throat, but now's not the time to complain. Not quite yet.

"...Hi, girls." She sees five faces soften as each turns her way. Identically zero avenues of conversation are presenting themselves to her.

But the ball's not in her court; the strange ponies in her house all explode into smiles. "Good job staying alive out there!" says Rainbow Dash; "Oh my goodness gracious, I've never been so relieved," says a practically fainting Fluttershy simultaneously.

It's Applejack who first addresses her with something remotely substantive. "Hey, partner," she says, voice low and cautious. "How are you holding up?"

Twilight sees Pinkie Pie look over, attention hanging on the question. "Uh... surprisingly well. I escaped, but I had to go back because I for—because... because I had to get Spike," she meekly explains. "Is anypony hurt?"

"No, dear, we're all unscathed," replies Rarity. "However, I don't know whether that can be said about the whole town..."

Twilight recalls her gallop to town hall, scanning the memories for blood, but it's a technicolor blur. "I don't know. But there was nopony in town hall when I got there, so anypony hurt was still in good enough condition to leave. With help, maybe."

On that note, Fluttershy has to take a seat on one of the library couches. "Thank Celestia," murmurs Tinder.

Twilight stops blinking for a few seconds. She feels a familiar weight slowly rolling back down onto her, at the mention of her name. She can't reign the question in any longer, though she tries: "Why... what are you all doing here?"

"Well... a couple different reasons, to be honest," admits Applejack. "We know you don't have strong ties to anypony in Ponyville, and we didn't want you to be alone at a time like this. Coming from out of town, you must be scared half to death without somewhere homely to be." She turns from Twilight to face the closed window. "But we also figure now ain't a bad time to have such a smart pony around, for our sakes, either."

A pause, as she waits for somepony else to take up the mantle, but nopony does. "...We wanna start brainstormin' what we can do against Nightmare Moon. So Tinder and I thought we would try roundin' up all of your friends and comin' over, except Derpy's at home, 'cause she has foals to think of. But you two weren't here. We know you don't take too well to surprises, so Rarity volunteered to stand at the door to warn you, in case you came late. We were about to run back to town hall to see if you got... held up."

You mean crushed, thinks Twilight. And it's not just the surprise that bothered me earlier. But... 'all my friends'? All these ponies consider themselves my friends? Or at least Applejack or Tinder considers them such. And either way, they all agreed to come. Probably, word just got out about my talent before the festival, and they want to cluster around the strongest mage they can find. But even if that's the only reason, she can't say she minds the recognition. Just the ponies that come with it.

"Well, we're definitely fine." She starts eyeing books on the nearest shelves. A Pegasus's Guide to Botany. Falconry for Dummies. "But how, exactly, do you think ponies like us can protest the reign of somepony like Nightmare Moon?"

"We were, uh, hoping you had some ideas," shrugs Rainbow Dash.

Twilight has plenty of ideas, none of them failing to end in pony extinction. Right now, it doesn't even matter. "I have something I need to do, before I can handle that conversation." As everypony's gaze follows her to the wall nearest the door, she feels behind the checkout desk with her magic, and passes a quill and parchment to her assistant.

"Spike..."

"Twilight... are you su—"

"Take a letter."

My Princess Celestia,

Tonight, every pony in Equestria looks to the sky. We need you. I beg you, Princess, come back to us.

Your faithful student until every star falls,

Twilight Sparkle

Spike rolls it up and consumes it in his brilliant emerald flame.