Rainbow Dash settled on a cloud, taking in every detail of her surroundings. The snowcloud she was on was soft, and much smaller than a wild one would be. Around her, similarly small snowclouds floated. None of them had drifted together and merged, so they must have been made recently.
Out of the corner of her eye, she caught a flash of movement. For a second, she thought it was something she could fight, but then realized it was just Fluttershy struggling to keep up with her.
Fluttershy finally lay on the cloud a minute or two later, breathing heavily from her physical exertion and stretching her wings out. She probably wouldn't be up for a pass over the surrounding area.
"Shy, I'm gonna do a flyby of this place and look for anything interesting, all right? We can cloud-beacon if we need each other."
Rainbow Dash sped off to the town's center after seeing Fluttershy's nod. From there, she started spiraling outward - if there was anything in the center of town, and there probably was, she'd have plenty of chances to catch it.
As she flew, Rainbow noticed something puzzling about the broken buildings below. Many, but not all, had been broken in a way that looked purposeful. Windows had their panes removed but not broken, buildings had their chimneys sliced off, and houses had some bricks removed without being damaged. It felt like living in an incomplete puzzle.
Further out, she flew over the path her group had entered the village through. Below her was a group of huge bugs. Changelings? In Equestrian lands? Heck no, not after what they'd put her through during the wedding.
She flew down and buzzed them, before pulling back up. A couple hissed and lit themselves on fire, but none of the bugs broke off to follow or launched magic at her. And, on second thought, they were redder and less lingy than changelings. Probably not even the town's monsters - she hadn't seen fire damage when she was doing her flyover. Must have been wildlife.
So she knew that the bugs below weren't the monsters, and she'd seen that the pegasus she was looking for wasn't visible in any of the open spaces she'd flown above. That meant they must have been in the only place nearby that would shield them from her sight - the mountain range. She was above the nearest mountain in a flash, now that she wasn't flying slowly to try to take in all the details she could.
A blur of something white below, difficult to make out against the background, caught her attention. She perched on a psuedocumulus and tracked whatever was moving below. It was the shape of a large pony - a promising lead.
She needed to make a beacon. Thankfully, there were even more snowclouds over the mountain than the town. Rainbow pushed a few nearby ones together to make a large thundercloud, and tossed a hoof-sized cloud at it from more than a few bodylengths away. There was a massive crash, something that Fluttershy should have been able to hear from where she was. She perched on the psuedocumulus again; now she just had to wait for the slower pegasus.
The ponyish thing below hadn't reacted to the thunderclap she'd just shot off. It still continued a pattern of walking up the slope, and then turning around and blurring in a controlled way as it traveled downhill. She wasn't as familiar with ground sports as with flying ones, but it looked like a snowboarder. At the speeds the boarder was going, they must have been a pegasus or earth pony (or not a pony at all - she wasn't sure how fast zebras and Arabians and stuff were).
The twists and curves the snowboarder below made were surprisingly repetitive, and Rainbow found herself falling asleep watching the pattern they traced.
-----------------------------------------------------------
"Uhh, five more minutes", Rainbow groaned, as she felt somepony else pounce on her cloud and start lightly tapping a hoof into her side. Stupid guard academy waking cadets up in the morning.
The pony whispered at her, way softer than a guard would have. "Umm, Rainbow Dash, you hit a beacon?" Wait, why was Fluttershy in the academy?
Oh, right, the academy was ages ago. She was near Mysteryville or wherever now. The realization that she was still in maybe-hostile territory brought Rainbow back to wakefulness pretty quickly. (A common saying with most ponies she had worked with was that she got away with taking a lot of naps on-duty by being really good at waking up when she needed to.)
She looked below her cloud as she started talking, to confirm that the pony of interest was still there. "Fluttershy, there's somepony down there. They just keep snowboarding." Rainbow pointed a hoof at the blur, which was still on the same exact path as before. Fluttershy looked in the same direction, taking a few moments to find the person being pointed at. "Right there. Didn't get distracted by my beacon, didn't stop moving on the same exact path and do something else the entire time you were on the way."
"Um, I only took a few minutes. And I think that's actually skiing."
"Skiing, snowboarding, whatever. They're both ground sports. My point is that they've been repeating the same routes the entire time, Fluttershy." Rainbow glanced at her friend. "I want you to wait up here and keep an eye on me while I check them out. If anything happens, let the others know."
Fluttershy shivered, as if she was terrified at the thought of anything happening, but she still nodded.
Rainbow leaped off the cloud, and headed to the bottom of the track. The snowskier would slow down when they got here, so she could ask them some questions. She'd be completely visible while they approached the end, too, so they hopefully wouldn't be startled and run.
She'd timed her landing correctly. A moment after Rainbow had landed, the mystery pony turned sharply from behind a group of small, dead trees and came into view.
Now that she was close by, she could see just how weird her suspect was. The front legs were longer than the back, and both were longer than the three tribes' legs, giving it the appearance of one of those enormous monkeys she'd seen at the zoo. The very bottom of its back hooves were freakish, a flat surface way larger than its front two hooves. Every part of its body was overly muscled, even its face, like a grotesque parody of the unrealistic-bodied kind of stallion you saw on Harley Quinn covers. Its middle was the creepiest bit, though. The entire region between its front and back legs had been replaced by two large diamond-shaped masses of muscle and flesh, connected to each other by the tips where the exact midpoint of a pony's body would be. Some sort of chain of weird beads wrapped around the connecting point. Both flesh masses were covered in pictures of diamondy flowers, with the most obvious being the one on the pony's flank-equivalent.
Was it a monster? There weren't too many pony-like monsters that she'd heard of, and not one of those had cutie marks. Maybe it was a divergent pony type, like the crystal ponies up north.
Well, she'd say hi when he saw her. If it was one of the ponies she came here to help, she wasn't going to be racist or anything. And if it was a monster and fought her, she could buck it in the face.
It was staring hard at the snow-covered ground when it came out of the trees, so she waited for it to come closer and notice her.
A tenth of the way to her, it hadn't looked up.
Halfway to her, it hadn't looked up.
Three-fourths of the way to her, it hadn't looked up.
She decided to help him out a bit. "Hey! Big guy!"
No response. He just slowed down and ignored her. Maybe he couldn't hear? She'd heard some ponies couldn't hear, although she'd never met any.
Okay, she'd just have to get his attention another way. At this point, he'd come to a complete stop, so she didn't feel bad about coming up to his side and poking him. "Hey!", she yelled, because maybe talking louder to a deaf pony would work. "Royal Guard! Got some questions for you!"
The pony, still staring at the ground, turned a tiny part of the way toward her. Then did that again. Then again.
She decided to save time by hovering directly in front of his face, and he finally moved his head in response.
He was staring at her flank, now. Was he checking her out? Ugh, she was no Rarity, but she had some standards. One of those standards was the stallion looking like a real pony, and another was her not being on a dangerous mission with the lives of her friends at risk.
"Hey, I said I had some questions!", Rainbow said, poking him on the nose. The stallion looked up her leg, finally looking at her face. His ears were pinned back, tail swishing and body tense. Rainbow tensed in response. Was he going to fight her?
Apparently not. "Aaaaaaaaaaaaaaaahhhhhhhhhhhhhhhhhhh!" The pony screamed and sped downhill. Rainbow just stared after it for a moment, unsure how to react. The way it moved, she now noticed, was pretty weird. It stood on its back hooves, bringing its front legs down every so often to gain momentum. There was no snowboard or anything with it.
The realization that what was either a suspect or a witness was getting away spurred her back into action. She flew after him, easily keeping pace thanks to her amazing flying skills. He looked back and made an impossibly sharp degree turn when he saw that she was following.
The turn forced her to bank hard, and cost her a bit of speed. The freaky pony clearly noticed this, because he had turned again to a large, dense grove of trees nearby. She'd have to slow down if she wanted to be able to turn enough to dodge everything there. She wouldn't be able to come at him from above, either - the treetops would be too covered in snow and branches for her to plow through.
------------------------------------
"I think I can trick that weird pony down there into running into you, when you come down", Rainbow Dash explained as she hovered in front of Fluttershy's cloud. "Not sure he'll react though. Didn't look me in the eye, keeps repeating his path when I'm not around, doesn't react when you talk to him, and stared right at my flank."
Fluttershy looked a bit surprised at that. Rainbow wasn't sure whether to be mildly insulted or not. "Um, Rainbow Dash?"
"I mean, I basically know what's going on here now. Oddly repetitive motions? Freaky large muscles? Not reacting to awesome ponies? Obviously, he's a ghost - "
"I think I -"
"- a ghost from some post-alpacalyptic mutant wasteland that used to live here before dark magic hit and they started fighting with each other over the water that was left -"
"We're surrounded by snow, Rainbow, and I think it's actually -"
"- and now they're a bunch of dark magic ghost monster psychics who roam a deserted wasteland, trapped here for eternity, doomed to check out hot girls and -"
"Rainbow Dash." Fluttershy's teacher voice was a terrifying thing, capable of getting any overexcited filly or colt to listen immediately. Rainbow immediately stopped talking.
Fluttershy continued. "What you described sounds like some of the foals I work with at the school."
Rainbow raised her hoof, waiting to be called on. Then she remembered how old she was. "Your foals are ghost monster psychics?"
"I mean the behavior is similar. Sometimes we get a colt or filly who doesn't react much to people, and makes the same gestures over and over. Twilight called it artism; it's like a disability, except it happens to the mind. When I was watching you two talk from up here, the way he acted looked almost exactly like one of those kids."
"So you think he's an artistic foal?" Rainbow turned to stare at the snowski tracks below, but couldn't see any sort of picture emerging. Must have been one of those art no-view things Rarity always went on about.
"I don't know if he's a foal or artistic for his species or tribe, but I can talk to him as if he's one. My cutie mark means I'm good with children, but Twilight made me take lessons on how to teach artists just in case. If he's not a foal and my talent doesn't help, I can just use what I was taught. And even if he's not artistic, he's similar enough that he might respond to those methods. But part of what I was taught was that I should talk to him by myself and figure out how he reacts to things before having him talk to others, which means, well, um..."
"You want to go after him alone? Fluttershy, you're great and all, but you're no guard or Princess."
"I can go in with you flying above me, keeping an eye out. If I look like I'm in danger, I'll break a beacon and you can swoop in and grab me. I mean, if you don't mind, that is."
At the look Fluttershy gave her, Rainbow sighed. She wasn't going to be argued out of this. "Alright. Grab a cloud and let's go."
-----------------------------------------
Fluttershy emerged from the thicket dragging an unused beacon-cloud. A second later, she bumped into a pegasus floating in wait for her.
"Well? Did he hurt you? Do I need to break his bones? Or whatever he has instead?"
Fluttershy shook her head. "He's agreed to bring us to some of the others in this town. You just have to cover your flank", Fluttershy said. "I don't think he was checking you out earlier, just scared of your cutie mark."
"What?", Rainbow asked, even as she gathered snow to rub into her fur. "It's a wing and shield. They're awesome, but not really scary."
When it became obvious that Rainbow could not actually reach her flanks with the snow she was carrying, Fluttershy approached and started to rub the snow in. After she was done, Rainbow looked back to check it out. Her cutie mark didn't look like anything meaningful any more, but at least the shield wasn't visible.
"I'll tell you the story as we walk, Rainbow Dash." Fluttershy walked back into the forest, and Rainbow followed. "It all started with a mare named Starlight Glimmer..."