Bat pony. Pegasus. Unicorn. Pegasus. Earth pony. Dustin was starting to get tired of the transformations, but each one told him something unique about the species. Earth ponies definitely had the best stamina. Pegasi were fast, but bat ponies had better reflexes. Unicorns were almost universally bad at physical things, although Night Light and Twilight Velvet had given him demonstrations showing that unicorns can train to correct that.

Dustin, an earth pony stallion, was waiting in the transformation booth again, ready for his next change. This time, however, he had a series of puzzles to work on. Lifting his head, Dustin nodded to Princess Twilight.

"Remember, you don't have to solve all the puzzles. This is training, not a test." Running down her test procedures, and made sure that all her equipment checked out. "Starting up in five, four, three…"

Focusing to avoid tension, Dustin started to work on the puzzles. He was halfway through putting the right shaped pegs in the right holes when Twilight started the spell. Each time the spell worked it started and progressed slightly differently. Dustin's face changed, his vision narrowing slightly while the snout on his face pulled inward. He finished getting the last peg in the right hole.

With a hoof that elongated out into a hand, Dustin pulled the color-pattern toy next. Bopping the crystal on top, it repeated a pattern among four other crystals. He poked the crystals in sequence only to be shown a longer pattern.

Twilight Sparkle watched as Dustin performed the puzzles as his body changed. Legs changed to arms, tail withdrew completely, and his spine adjusted itself to an upright body. All Dustin's fur just magically disappeared, and he was soon left naked in the chamber.

Dustin's body looked too familiar to Twilight. She stared at his naked form, that she was familiar with from other tests, and found herself blushing. "Okay, Dustin, if this follows the same trend you should have four and a half minutes."

He wasn't completely human. Dustin still felt little shifts and movements inside him, but he was getting closer. A twist in his gut, as he did a forty-color sequence on the crystal box stole his focus, and he messed up the last few colors. He moved on to the next toy.

"Not at apogee yet." As he spoke, Dustin could still feel his insides shifting. Outer appearances were the fastest to change, he had discovered, while internals seemed to be the last. At least sometimes. Then, as he solved the next puzzle, things felt complete. "Human fully now."

Twilight pressed the button on one of the magic clocks. "Starting timer. How are you feeling?"

"A little cold, slightly short of breath. As normal. I know you can't do anything about our altitude, but can I at least get some kind of heater in here?" Stacking blocks, Dustin finished the pattern and moved onto the next test—which was actually a test.

Dustin started crossing off answers in the multiple-choice. "You wrote this one, didn't you? With your hoof."

"I needed to practice!" Twilight felt defensive. "While this spell is running I didn't want to use any magic for fear of contaminating the transformations. Added to that I still need to talk and I had to get better with my hooves."

"Keep working on it." As he worked, Dustin shivered a little. He was soon past the multiple choice questions and into an essay. His hand flew across the page until he noticed something odd about that hand. "Transformation's starting again. How long was the apogee?"

"Four minutes and twenty-three seconds. That's almost enough time, Dustin." Twilight stared at Dustin's hands, watching talons appear as several fingers merged together.

"Don't know what I'll be this time. Three claws and a thumb… Griffon?" His hand still held the quill, so Dustin ignored the changes and kept working.

"Could be. There are a few—" Twilight gasped in surprise at the latest change: Dustin's feet had become pony back legs. "Scratch griffon. Hippogriff is the only species with that configuration. There go your wings."

The changes weren't painful, but they did leave Dustin feeling stretched and distorted. New limbs grew on his back, and because he lacked both fur and feathers they were the silliest, naked wings yet.

Prick by prick, feathers started sprouting along Dustin's wings. He stretched them out and gave them a few flaps. "I don't think I remember that one. Hippo is pony, right?"

"Hippogriffs are a pony, but featuring aspects of a bird. So you get talons on your forelegs, a beak, and bird wings." Twilight was already relishing doing a full physical on Dustin—she hadn't had a chance to do a full workup on a hippogriff yet.

"So the front end isn't mammal at all? Great, bird-bits." As Dustin spoke, his tone shifted to a higher register. The changes involved his face and neck now.

Growing a beak was a singularly unique experience for Dustin. His lips twisted and started to harden, then fused back into his skull and jaw. Still there was no pain, but the feeling of his hardened lips stretching out into a beak made Dustin cry out in surprise.

Twilight winced at the sound. "Dustin, are you okay?"

Trying to reply, all Dustin managed was an annoyed squawk. His tongue was still stretching, making matters worse for any attempt to talk. In the end he just held up his hand, curling his thumb and his finger together.

With a soft, warbling sigh, Dustin returned to his tasks. Writing with bird claws wasn't impossible, but his center of balance was shifting. Fur began to grow on his legs and arms, with a little prickle of it starting on his face.

"Wow, that's a vivid purple fur, and I love the blue and silver mane." Twilight's eyes were wide, the effect of Dustin's coloration put him quite close to her own pattern, except for the silver streaks. "Can you give me a percentage estimate?"

"Triii." Dustin clamped his beak down. Wiggling his tongue, he tried again. "Twiiii—" Walking to the window of the chamber, Dustin breathed on it as much as he could. In the resulting foggy window, he wrote a backwards twelve.

Not being able to talk was annoying. Dustin ground his new beak a little in annoyance. Pressure grew at Dustin's rump, and he turned just in time to see a plume of color sprout from his tail-nub. As intensely purple fur spread over his hips, he got to see the same effect Twilight had just described about his mane.

A trembling between Dustin's back legs, familiar now, was all the warning he got or needed that his penis was shrinking away. Female, now, wasn't the terror it had been the first time for Dustin. The shifting of his sex was almost pleasurable in the same way everything else was almost painful.

While Dustin finished off the essay answer, she could feel the new body cavity grow inwards. For any man it would be a singularly shocking and surprising sensation, but it was one she was growing used to.

By the time Dustin set the essay aside, her insides were starting their dance. "Changes moviiii—" Dustin clamped her beak shut. She realized it was a particular sound that her mouth got stuck on. "Changes gone…" She pointed at her midsection. "Can't pronounce… Iiiiii— Getting stuck."

"Vocal reproduction problems shouldn't be unheard-of. So far you've only had pony or human mouths to work with." Twilight kept scribbling notes with her hoof. "Limb test, please."

Dustin put down the blocks she had been trying to stack in a special way. Lifting her right foreleg, she tested all the joints, right down to her odd fingers. "Works okay." She repeated the test with the other foreleg.

Back legs were more of a standard test, with Dustin lifting and turning each in all their ranges of motion. She gave another okay for them. Then she moved to her wings. Stretching them proved a problem: with her feathers fully grown, her hippogriff wings gave her a longer wingspan than the booth was wide.

"Problem testiiiing wiiiings." Dustin wrenched her beak closed each time, starting to get the hang of her mouthparts wanting to screech. "Thiiiis iiiiis worse than when I was a bat pony. Okay, tail check." She flicked her tail left and right, then flagged it. "Seems to be workiing."

"Getting better with that beak. Keep talking if it helps. Female again?" Scribbling down Dustin's replies, Twilight Sparkle was still excited about the side-project of getting to know different species better.

"Yeah, mare again. Thiis is all prettyy normal now. Belay, how's Kiera?" Dustin shivered as she felt more of her insides shift around. She waited a few moments further. "Belay?"

Scratches voice came from the comms button. "Dustin, you need to come quickly. Kiera's losing her synapse links faster now."

The bottom fell out of Dustin's world. She stared at the wall in panic. "H-How long does sheee have?" She was already moving, even with only four of her six limbs at all familiar, grabbing her comms button and her little saddlebags.

"At present rate, fourteen hours. At present rate of decay, six hours." There was a hint of emotion in Scratches' voice, but being an AI they didn't have access to a more natural speech synthesis.

"Wait, Dustin!" Twilight teleported herself to the doorway of the booth. "What's wrong?"

"Kiiiera's fading, Twiiliight. How soon can we do this again?" Dustin hated the interruption, but knew Twilight needed to be told.

Twilight could hear the urgency in Dustin's voice. She ran the numbers quickly in her head—it was Dustin's second transformation process for the day. "We should wait until tomorrow—"

"I don't care if I get stuck, or mutated, or what. Can you set this up at Kiera within an hour?" Dustin clamped down on her voice, managing the first full sentence without squawking.

Biting hard on all the scientific arguments she could use, Twilight gave the only answer a friend could. "Yes."

Heavy work with hippogriff claws was very doable, Dustin discovered, but much finer than wielding a quill was much worse. Still, less than an hour after first finding out about Kiera's decline, Dustin was helping Twilight carry her equipment off the train.

Twilight had a lot of her things floating in her magic, but she could see the pain on Dustin's face (even with her hippogriff features), and gave her something to carry. "You know the risks. We have no idea what might happen if you transform again without your aura having time to settle."

"But you're going to do it?" Dustin's muscles strained under the weight of the heavy crystal she was carrying. When Twilight didn't respond, Dustin turned her head to look the Princess of Friendship in the eyes.

"Yes." Twilight mentally added, Because if I don't, Kiera will die alone in the dark. She didn't want to say the extra words out loud—just thinking them hurt her. "I will."

Reaching the lift without any further words exchanged, Dustin put the crystal down for Twilight to start building the transformation rig. "Kiera? Belay?"

"I read you, Dust. You sound different." Belay's voice was clear through both Dustin's implant and the comms button. "Kiera managed to play her unlock tone. You just need to come up now and unlock—"

Dustin took a deep breath. "Negative. My code is: two, five, five, seven, one, zero, zero, zero, nine, eight, five, seven. Repeating—"

"I got it, Dust. The column's open. Ready when you are."

"I have the lift ready." Scratches' tone was neutral again.

Dustin reached one claw up and touched the lift. "Okay everypony, let's do this." She turned back to see Twilight powering the machine. "Princess, are you ready?"

"I'm ready. You have all your tools?" Twilight saw the shocked expression on Dustin's face.

"I'm getting them out." Belay's voice was sharp, as if she were moving around already. "Get started, and they'll be ready when you get here."

Dustin walked over to the machine and stepped onto the marker where the probes were. "Okay. Hit it." She felt the bloom of magic around her, like usual, and felt it sink into her body. "Tell me the moment the spell is done."

Twilight watched as Dustin's face started to change—beak pulling inward. She could only nod and turn all her attention back on the controls.

It felt, to Dustin, like every part of her was changing at the same time. It was different than all the rest of her changes, even as all of those had been different. Her forelegs changed to arms, talons to hands, wings pulled in completely (as did tail), and her back legs restored to their human shapes.

"Okay, the spell's finished!" Even as she yelled out, Twilight could see something fundamental had changed: Dustin was still female as a human.

Author's Note

Kiera: do you feel a song coming on?

"I'm scared, but I don't want Dustin to hurt himself to save me. Please stop him." Kiera's words were almost choking sobs.

So I do this "Ask X" thing. X can be any pony within the story. You can ask them anything and they will definitely, hopefully reply. Keep the questions appropriate to the age-rating of the stories, and they will answer the best question in the author notes of the next chapter. The more votes a comment has the more likely I will get it to the right pony to answer. Try to keep it to one question per post! They will pick one question per chapter.

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