Author's Introduction
It has been a long time since I've written a fanfiction - a decade, at least. I think I'm very out of practice. Nevertheless...here we go! Gotta get back into the habit at some point. As much as Friendship is Magic is largely built on character pieces and "slice of life" stories, however, I can't help but want to write a nice adventure piece, so that's what this is.

Thanks for reading, by the way!

---

Chapter One

Ponyville

Twilight Sparkle wrinkled her snout as she looked out her window. About an hour ago, she'd realized that she should have been asleep long ago, and promised herself only one more chapter of Goldhoof's Gargantuan Guide to Grimoires. Of course, one chapter had turned into two, then three…then four…

But she was certain that she had seen the stars fading from the sky as Princess Luna collected them and began lowering the moon. The lavender unicorn stood from where she had ended up on the floor next to her bed, and stretched, trotting over to her window and glancing outside. From the looks of things, it was midnight – the moon was suspended high in the sky, and the stars were scattered…oddly. Twilight realized she didn't recognize the constellations – it was as though Princess Luna had essentially just thrown the stars into the sky and been done with it. But the pony had been to the library's observatory at the start of the night – the stars hadn't been arranged so haphazardly…and Twilight could hear the morning birds chirping to each other, waking themselves up and getting ready for a new day.

But it was midnight…wasn't it?

There was a knocking on the door, the sudden loudness of which nearly caused Twilight to leap from her coat in fright. Composing herself, she descended from where she had been, on the library's second story, and down the front door. "Who is it?" She called. Not that she didn't trust the ponies of Ponyville – it was just that old Canterlot habits didn't die easy.

"It's Applejack," came the familiar twang of the orange pony's voice from the other side of the library's door. "Ah think we've got ourselves a problem."

Twilight called up a little bit of magic to open the library's door, stepping aside to let her Stetson-hatted earth pony friend inside. "What time is it?" The unicorn asked, barely suppressing the urge to yawn. Now that she wasn't reading, the hours of missed sleep were beginning to catch up with the pony.

"That's sort a' why I'm here, Twi," Applejack said as she came in, scuffing her hooves on the mat inside the library as she did to wipe off mud. The weather schedule had called for a light rain over the past few days, and the roads outside were still muddy. "Ah get myself up every morning' at the crack a' dawn. Only this mornin', there weren't no dawn to get up to! Thought maybe you might have an idea as to what the hay is goin' on."

Twilight glanced out the library window, at the unmoving moon in the sky. "I thought something was wrong," she intoned, scuffing the floor with her hoof as she thought aloud, again fighting the urge to yawn. "A few hours ago I thought I saw the night drawing down, but when I looked a moment ago the moon was back up and the stars were out of place. It's almost like Princess Luna decided to put them back up in a hurry…"

"Maybe," Applejack said. "She hasn't been back long, maybe she's outa' practice or somethin', so decided to give it another go."

There was a long, uncomfortable silence between the two ponies. After a second, Applejack began to fill the void. "Or – "

"No way," Twilight interrupted, before her friend could finish the sentence. She saw where it was going, but refused to even think about the possibility. "Just no, Applejack."

The earth pony shook her mane. "Okay, Twi. But ah think you should maybe write Princess Celestia, see what's goin' on."

Twilight sighed, though the action caused her to finally lose the battle against yawning. "I can't," She said after a moment. "Spike's in Canterlot right now on royal business," she said, glancing out the window at the motionless moon. "Look…maybe you're right. Maybe it is just Princess Luna…out of practice, or something. I'm sure that pretty soon she'll start drawing down the night again."

"Ah hope so, Twi," Applejack said, clearly unsure. After a moment, she laughed a little. "Maybe Princess Celestia caught a cold or somethin'. That's probably all."

"…sure," Twilight said, deliberately deciding against wondering if the immortal, physical goddess alicorn that was Princess Celestia even could get sick. She decided instead to focus purely on the one upside to it apparently being midnight. "Well, as long as it is still night, I guess I should get some sleep. And I guess you've got a good reason to sleep in for a change. Right?"

The orange earth pony guffawed a little at that, as she headed out the library's door. "It'd have to be pitch-black for that to happen," she said as she opened the library door again. "Moon n' stars are bright enough, and them apples don't care much if'n it's day or night. Need to be bucked one way or another."

"Right. See you later, Applejack," Twilight bid farewell as the earth pony wandered off. Twilight, meanwhile, trotted off and upstairs, climbing into her bed. Despite how tired she realized she was – there were times, not very often but they did exist, where she hated books and how enrapturing they were – she found herself with eyes wide open for the longest time, simply staring at the moon in the sky.

By the time exhaustion finally overcame the lavender unicorn, it still hadn't moved even an inch.

---

"Something is officially not right," Rainbow Dash said as she sat atop her self-made cloud palace, watching the stars and the moon and how much they were not moving. Without the movement of the sun or moon to judge time, the pegasus had no way of knowing just how long it had been since dawn was supposed to come; by her best guess, it should have come at least four or five hours ago. Instead, the night continued to stretch onwards even as Dash leapt from her home and began a slow glide over Ponyville.

She was, by now, not the only pony to notice. Natural inclinations had woken up most ponies in Ponyville by now, and each of them had turned their eyes to the still moon and wondered what the hay was happening. More than a few times, a pony had called up to her and asked if she had any idea, and each time Dash had been forced to respond with a negative.

More than a few times, she'd also heard somepony mention the name Nightmare Moon. Dash;s mood grew grimmer at that as she made a beeline for Twilight's tree-library and let herself in through Twilight's window, which was open – the weather schedule had, after all, called for today to have been a hot day to help with all the mud outside. The lavender unicorn was curled up under a blanked on her bed, mouth hanging open slightly and front hooves embracing her pillow like it was a teddy bear. At the sight of that, Rainbow Dash's first instinct was to leave the unicorn as she was, at least until she could find her other four friends and give them something to add to their pile of things to tease Twilight about.

A glance outside, however, reminded the cyan pegasus that she had come here on serious business, and that any teasing of Twilight would have to wait. Never a particularly gentle pony, Dash walked over to Twilight's bed and grasped the sheet she'd covered herself with, yanking it off quickly. "Alright, up and at 'em," She said aloud. To her surprise, Twilight did little more than roll over and curl up into a ball. She must have been exhausted.

"Twilight," Rainbow Dash said, jabbing her friend with a hoof. "Come on, wake up. The sun hasn't come up and – "

"Mnph," was the only response Dash got, as Twilight grabbed a pillow and put it over her head, still ninety percent asleep. "Told you already, Applejack…nothing wrong…just wait a few hours…"

The cyan pegasus shook her mane a little in agitation. "Uh, it's Rainbow Dash, not Applejack."

Twilight turned to look at Rainbow Dash, eyes only partly open and yawning. "Oh," she said. "Hi, Rainbow Dash. Why are you here?"

In agitation, the pegasus jabbed a hoof out the window. "That," she said, indicating the still-unmoving moon in the sky. "It should have been dawn hours ago, Twilight!"

The lavender unicorn opened her eyes fully as she regarded the moon. She snapped fully awake at the sight of it. "Still nothing?" She asked as she got out of her bed. "Applejack was here earlier…we guessed that maybe Luna was just out of practice or something."

"Yeah, or she's turned back into Nightmare Moon." Dash said, before Twilight's still sleep-addled reaction could stop her.

She shot her friend a glare. "No." She said firmly. "Didn't we just do this last Nightmare Night? We saw the Elements of Harmony transform her back. We saw how happy she was on Nightmare Night."

Rainbow Dash lifted herself up off the ground with her wings. She was always more comfortable flying than standing anyway, but this gave her a few feet on Twilight as well while she made her point. "But we still need to do something. Where's Spike? We need to write a letter to – "

"We can't, he's in Canterlot right now," Twilight said, not intimidated. "And we don't need to write a letter because Nightmare Moon can't be back."

"Oh, sure," Rainbow Dash said, crossing her forelegs in front of her as she hovered. "It was just some other pony who can control the rising and setting of the moon."

Twilight winced at that. "Maybe she's sick?"

"Can the princesses even get sick?"

"I don't think so, no," Twilight said as she walked over to the window, chewing her lip. What had before been a mild worry was blossoming into something far larger in her mind now. She had helped Luna during the difficult time the princess had been facing on Nightmare Night. She'd spoken to her, played games with her, laughed with her. Nightmare Moon couldn't have returned. Luna didn't resent the ponies of Equestria anymore.

But…

"Maybe…" Twilight said. "Maybe…we should go to Canterlot. Just to see if everything – " She paused, then, as there was a flash in the sky, like distant lightning. Quite suddenly – faster than Twilight had ever seen it move – the moon began to drift across the night sky, as one by one the stars towards the east began to wink out as a glowing light began to edge its way above the horizon.

"Ah hah!" The lavender unicorn proclaimed, turning to the cyan pegasus, who had come back down onto the floor as she watched the moon's swift progress across the sky. "See? The moon is setting and the stars are being drawn down. She smiled as she watched the eastern horizon. "Told you everything was fine."

Rainbow Dash couldn't help herself – she breathed out a huge sigh of relief. "Thank Celestia," she proclaimed. "And thank Luna, too, I guess. What do you think happened?"

"Maybe Applejack was right and Princess Luna is just out of practice," Twilight ventured. "Or maybe I'm right and she was sick. Or…I don't know." She went back to her bed. "I'm going back to sleep."

Twilight expected to hear her friend take off at that, and from the sounds of things, Rainbow Dash had been about to. However, the flapping of the pegasus' wings continued for a few minutes too long, and Twilight turned to look at her friend, who was staring out the window, jaw hanging slightly.

"What?" She asked.

"…I think you should see this," Rainbow Dash responded.

Grumbling slightly, Twilight climbed from her bed, trotting over to her window and glancing outside. What could Rainbow Dash be so concerned about –

The sun was black.

Twilight Sparkle stared. She wasn't even sure how what she was seeing was possible, but there it was: the sun, rising into the sky, was black at its core, and the light that it shed from its periphery was…pale, almost sickly, and largely lacking in warmth. It seemed to rise into the sky only with great reluctance.

"I think we need to go to Canterlot," Rainbow Dash said after the two stared in utter confusion at this spectacle.

"I think you're right," Twilight Sparkle responded.