The Loss of Sunset

by SquiggelSquirrel

The plan

“Well,” said Rarity, pocketing her phone, later that same evening, “she is officially ‘not answering’. So much for that idea.”

“That might actually be fortunate,” said Twilight, “since we still don’t know what to say.”

The girls were standing outside a local walk-in clinic

“Maybe Sunset was right,” said Pinkie Pie. “If it makes them both happy, what’s the point in trying to stop them?”

“Because it’s a lie.” Applejack glared a little, nursing a now bandaged hand. “It won’t make either of them happy in the end.”

“Isn’t that Sunset’s decision, though?” wondered Rainbow Dash aloud.

“I’m certain Sunset Shimmer would intervene if one of us was taking such a dangerously selfish path.” Rarity said.

“And sooner or later the real daughter’s bound to show up.” Applejack sighed. “That’s not going to end well.”

“It might be the sooner the better,” said Twilight. “The longer this goes on, the worse it’s going to be.”

Pinkie Pie gasped dramatically. “That’s it! Girls, we just need a holiday miracle!”

The collective dubious stares passed between her and each other.

“It’s… not like they hand those out on demand, darling.”

“Nono, we just have to make our own! All we have to do is find other Sunset Shimmer, and then Honey Swirl will be so happy to have her real daughter back, she’ll be all ‘even though you aren’t from this world, you’re like a second daughter to me’, and Sunset will have a twin sister and everyone will be happy and tell the truth. It’s such a perfect ending, it just has to work.”

“Well… it’s not the worst idea we’ve got.”

“Actually I think it’s the only idea we’ve got. Well, at the very least the other Sunset might be able to convince our Sunset… but how would we even begin to look for her?”

There was a pause.

“I could try and sniff her out,” volunteered Spike, “if we knew somewhere she’d been recently for me to pick up the scent.”

“How would you even know what she smells like?” asked Twilight.

“I mean, she’d smell like a different Sunset Shimmer, right? Like the other Twilight smells like a different version of you. It’s like… I don’t know if there’s a word for it. Like a song you’ve heard before, but someone else is singing it?”

Twilight looked thoughtful.

“We could split up,” suggested Rainbow Dash. “Some of use look for the other Sunset, and some of us go try and talk to her mom.”

“I'm not sure talking to Honey Swirl is a good idea,” Rarity said, “at least until we know what to say. If we make an enemy of her before we have proof, she might not listen to use even when we do have something she would believe.”

“So, we just split up and search for the other Sunset? Start handing out fliers and hope?”

“That's it!” Twilight suddenly exclaimed. “Spike, you're a genius!”

“Okay?” responded Spike.

“If I just convert the overlapping frequencies into a Fourier space, I should be able to establish a baseline harmonic and apply an offset vector to establish the translated signature EM wavelengths. There should be some resonance to work off… if only I'd thought of this sooner, I… well, I'm not sure what the other practical applications would be, but I'm sure there must be a use for mapping the pattern offsets.”

Applejack was the first to respond to this proclamation.

“Twilight?”

“Yes?”

“What in the name of all sanity are you talking about?”

“Well, it's… um. Okay, d'you girls remember the, uh,” she held her hands up chest-high in front of her, thumbs and forefingers making a horizontal ring as if holding something circular up in front of her, “device?” She winced slightly.

“You mean, the one that turned you into a crazy she-demon?”

“Uh… yeah. But before that, it was meant to track and sample a specific set of what I thought were peculiar EM frequencies, but which turned out to be, well, Equestrian magic. And before that, I had another device that was just a tracker, with none of the sample collection functionality.”

“With you so far, I think.”

“In theory, I mean, this is just based on my current working hypothesis, but I might be able to create a modified version of that tracker and use a sample from our Sunset — I already have some of her hair in my room — to track down this world's Sunset, assuming… well, quite a few things, but I think it's worth a shot.”

The other girls exchanged glances. Applejack shrugged. “How long do you think that will take?”

“Hmm… a few hours, maybe. I think I could have it ready this evening.”

“So…” Applejack looked around at the other girls, “is this our only plan? Don't get me wrong,” she added, turning back to Twilight, “I think this sounds worth doing, I'm just wondering if there's anything else we should be doing.”

Pinkie Pie put a hand on Applejack's shoulder. “Just accept the plot device, Applejack. There's clearly no other way.”

“Um, ” Fluttershy offered, “I could research some old newspapers, maybe find out something about the other Sunset.”

“I could phone around,” said Rainbow Dash, “someone else has got to know something.”

“Ooh! I'll help with that!” offered Pinkie Pie.

“Do you need any help with your doohickey, Twilight?” asked Applejack.

“Hmm… someone to help with to soldering while I write the code could help."

Applejack flexed the thumb and forefinger of her bandaged hand. “Yup, I reckon I can help with that.”

“I'll set what I can do online,” said Rarity, “social networking might be more help than boots on the sidewalk here.”

“Okay, we'll meet back at Twilight's house in the morning, unless someone finds something sooner.”

The girls nodded, and parted ways. Applejack stayed with Twilight a moment after.

“It's going to be okay, sugarcube,” she reassured Twilight, “with all of us working together, there's nothing we can't figure out.”

Twilight smiled. “Thanks Applejack.”

---

Applejack hadn't seen Twilight's "laboratory" before. The piles of half-dismantled appliances, the wall of conspiracy-theorist red strings, the seemingly decorative Jacob's ladder and lava lamps all gave the impression that she'd stepped into a movie set of a mad scientist's lab. On arrival, Twilight strode across the room, hitting the power button to start up her computer as she passed, and pulled open a desk draw. After digging out a circuit board, a notebook, something that appeared to have one been a hair drier, and a box of latex gloves, she straightened up with something reminiscent of a multimeter held triumphantly aloft.

Applejack navigated her way across to what appeared to be a work bench, with various tools piled up towards the back, and gingerly removed a tray of papers from the adjacent stool. There were shards of broken red crystal held in Petri dishes on top of the papers; Applejack frowned at recognising fragments of The Dazzlngs' shattered pendants.

Twilight, meanwhile, had somehow acquired a labcoat and a pair of goggles in the moments Applejack had looked away. She now sat in front of the computer, fingers clattering across the keyboard as reams of code and diagrams danced around the screen.

“Just a few tests to run before we start the wiring…” Twilight barely turned her head in Applejack's direction as she muttered aloud.

Applejack waited. The Jacob's ladder buzzed. The lava lamp blooped, which Applejack suspected wasn't meant to happen. A printer whirred and ground itself into readiness behind her, which made her jump. Paper began to feed through, with some fairly intricate circuit diagrams coming out. Twilight spun on her chair and jumped to her feet, striding across the room once more to snatch the papers up.

“Okay, so uh, would you be able to wire this up while I code up the controller circuit?” She presented the multimeter-esque device and the printed diagrams to Applejack.

“Uh, sure, I guess.”

“Great! Oh, and you'll need the display board, hold on…” She practically sprinted across the room to fetch another lump of unidentifiable electronics off a nearby shelf. It was circular, glassy, and had four wires dangling off it. She presented it to Applejack and indicated how it fit in to the diagram, grinning a little wildly for Applejack's liking. “Got it?”

“I… reckon I sure have,” Applejack forced a small laugh.

“Also great! I'll just be right over here if you need me.” Twilight gestured to the chair barely two meters away from where Applejack was sat, before darting back over and spinning herself back down onto the chair to resume coding.

It took Applejack the better part of two hours to re-assemble the device according to Twilight's specifications, including a brief break to fetch drinks for them both, since Twilight seemed completely absorbed in her work. Twilight was… different. Maybe it was the weird green light coming off whatever the thing next to her computer screen was, or the strange half smile that seemed to settle on her face as she worked, or the small giggles every time she made progress, but Applejack found herself unpleasantly reminded of the insane demon who had tried to rip apart the fabric of two realities after Twilight overdosed on wild magic.

She gently nudged Spike, who was currently curled up on a dog bed in one corner of the lab.

“She always get like this?” Applejack murmured to Spike.

“Mmm? Oh. Yeah, sometimes…” Spike yawned. “She'll sleep it off when she's done, usually.”

Despite Applejack's concerns, the pair continued to work late into the night, until finally the device was assembled.

“It… ” Twilight yawned, “it will need to run through the calibration routines, that will take a few hours. We should probably get some sleep.”

Applejack looked down at the finished device. It consisted simply of a ring of LEDs that could indicate direction, a handle, and a small box in the centre to hold a "sample". Wires connected it to Twilight's computer, where a stream of text was scrolling up across the screen.

“Sure…” she muttered. ”Sleep.”

---

When Applejack awoke the next morning, the other girls had already arrived. They sat around the kitchen table, discussing the results of their endeavours so far, as Applejack and Twilight ate breakfast. The general mood was heavy.

“So basically,” concluded Rainbow Dash, towards the end of breakfast, “zilch. We got nothing. If Twilight's machine doesn't work —”

“Pfft, silly,” interrupted Pinkie Pie, “of course it'll work, this is Twilight Sparkle.”

“Speaking of which,” said Twilight, “why don't you girls head over to the lab? I'll go fetch Sunset's hair sample and meet you there.”

“Yes actually, darling,” said Rarity, “I've been meaning to ask, but why do you have a lock of Sunset Shimmer's hair in your boudoir?”

“Oh.” Twilight froze mid-step. “Um, you know… for… research… purposes. Scientific research. Into, um, magic. Equestrian magic, and whether there are any anatomical, I mean, biological — cellular differences between humans from this world, and ponies who've been transformed by the mirror portal. On a cellular level. With a microscope. I just… happened to have a sample left over, from that research. Into science.”

The more Twilight spoke, the pinker her face became.

“Oh,” dead-panned Rarity. “Very well, dear. We'll head over to your laboratory while you retrieve your… scientific research materials.”

“Mmm,” Twilight affirmed, before quickly marching out of the room.

---

Once the girls were assembled in Twilight's lab, Twilight opened a small hatch on the tracking device, and inserted the coiled lock of red hair. She closed the hatch, pressed a button, and held up the device so all could see. Lights blinked around the outside a few times, then settled into a single throbbing light pointing in one direction. Twilight rotated the device experimentally, and the light moved around like the needle of a compass, continuing to point the same way regardless of how the machine was oriented.

“Girls,” Twilight grinned, “I think it's working!”