Fluttershy, Rarity, Applejack and Pinkie Pie were thrilled by the return of their absent friends. They'd been frantic after the incident in Twilight's library, and had found Spike and insisted that he send an emergency message to the Princess. Celestia responded quickly, coming to Ponyville in person to try and determine what had happened to her beloved student. After a quick investigation, she'd summoned her sister, Princess Luna, who'd written the theoretical treatise Twilight had based her spell upon.

The second Princess arrived as quickly as the first had, and immediately set to poring over Twilight's modifications to her research, which the Night Princess deemed "Absolutely brilliant!" Her careful analysis could find no reason for the horrible malfunction of the spell, however, and she suspected, given the quality of Twilight's work, that anypony who attempted the spell would suffer the same result. Shaking her head sadly, Luna had stated that she thought the only pony who could get Twilight and Rainbow back was Twilight herself; the spell was far too dangerous to meddle with.

The Sun Princess, however, was leading search parties all over Equestria, searching for her missing student. To her despair, every search came up dry, and the Princess of the Day was eventually forced to call off the search. It was said amongst the guards that Celestia was heartbroken to have to abandon her student.

Those left in Ponyville were grieving for friends they thought lost forever when the purple star burst over the Everfree. Fluttershy was the first to find them, and the quiet, gentle yellow pegasus was overcome with joy, hugging her friends so fiercely they had to remind her that they needed to breathe.

Rainbow figured out how to remove the human from his armor, and Fluttershy had insisted the wounded creature be taken to the hospital at once. She was seriously concerned about his leg injury getting infected, and was willing to defer her friends' story to help a creature in need.

They'd run into a group of ponies headed to investigate the flare on the way back to Ponyville. Applejack was in charge, and she'd been shocked speechless to see her missing friends. She hadn't even been able to move while Rainbow Dash sauntered up and stole her brand new hat right off her head, replacing it with the rather battered one the cyan pegasus had been carrying for the last three weeks. "Y'all are back. Yer okay! We were so worried!" She'd finally choked out, grabbing her friends in a fierce hug much like Fluttershy had done. After being given a brief summary of their story, she'd unhesitatingly leant her strength to carry the unconscious wounded human, taking some of the strain off the still-injured Rainbow Dash.

Upon entering the town, they'd encountered Pinkie Pie and Rarity. Pinkie was thrown into paroxysms of glee, bouncing around and chattering a mile a minute, and vowing to throw the "Bestest-best of all welcome parties, ever!" while Rarity gave a more reserved, though no less heartfelt, "Welcome back, darlings." They'd met Spike in town as well, and the little dragon had latched on to Twilight and refused to let go. He was happier than anypony had ever seen him.

Duran Thirk regained consciousness in the Ponyville hospital, only a few hours after he, Twilight Sparkle, and Rainbow Dash returned to Equestria. Finding that his stump was already sealed, he insisted on leaving his hospital bed immediately so he could fashion a crutch for himself. When the nurse insisted that the hospital would give him one when he was ready to leave, the human proclaimed he was ready now, dragged himself out of bed, and started crawling down the hallway. Rainbow Dash, being treated in an adjoining room, heard the commotion and went out to calm her bipedal friend, though she only managed to convince him to sit in the hallway while the nurses brought out a crutch.

When Twilight and Rainbow introduced the human to their other friends, they were somewhat surprised at how well he got along with Fluttershy. He stayed in a corner during the party Pinkie threw to welcome them back, though he apologized to the party pony early on for seeming antisocial. The pink mare just smiled and said, "That's okay. What's important is that everyone enjoys themselves, not how they do it!" Duran thanked her, and the cheerful earth pony made sure to bring him fresh punch every once in a while. Fluttershy, on the other hoof, stayed next to the human for most of the party, talking to him quietly while everypony celebrated the return of Twilight Sparkle and Rainbow Dash.

Twilight asked the yellow mare the next day if she knew the human was a predator. Fluttershy answered that, yes, she knew a predator when she saw one, but predators were living things too, and this one was hurt in more ways than one. She would help him if she could.

The two princesses arrived the next day, together. They both spoke to Twilight at length, both about her experiences and about the magic she'd employed. Luna, especially, was thrilled at how far the lavender unicorn had developed her theories, and Twilight promised to share a copy of her findings with the Night Princess before she published it.

Sadly, things went badly for a time after that. Three days after returning to Equestria, Rainbow Dash and Applejack were having a friendly argument while visiting Twilight's home about the condition of the cowpony's hat when the pegasus had returned it. Duran was listening and chuckling from the sidelines, when he suddenly mentioned he was a bit dizzy and laid his head down on a table to recover.

Ten minutes later, Rainbow noticed he still had his head on the table. She poked him playfully with a hoof, thinking he'd fallen asleep, but he fell over heavily onto his side, and she saw his eyes were wide open and staring. Unnerved, she and Applejack tried to coax a response from him. When that failed, they rushed him back to the hospital.

Everypony had been baffled. The doctors could find nothing wrong with him, he just wouldn't wake up. Twilight had written to the Princess again, emphasizing that the human's knowledge could potentially benefit all of Equestria. Celestia had sent several of the best doctors in the Principality, paid for by the Crown. They finally realized that the human was undergoing severe neural degeneration. None of them knew why. The truth was, it was caused by the antidote to murderpede venom Duran had used back on Hell's Reach. Unknown to anyone but the NAIS expedition commander, who'd kept the information in a password-locked file, there was a limit to the number of doses that could be safely taken, and Duran had exceeded that number. He'd been dying slowly when Twilight and Rainbow had first encountered him; the shock and trauma of having his leg amputated had accelerated his condition.

The six unicorn doctors Celestia had found, however, were very, very good at what they did. Even without knowing what had caused the human's condition, they were able to stop the degeneration before it reached his brainstem. Calling in a small army of colleagues they each knew and respected, the six worked in shifts around the clock; two worked, supported by friends and fellow doctors while the other four rested. Twilight Sparkle, Rainbow Dash, and their four friends were present in similar shifts, two at a time, talking and telling stories and jokes so that their friend was never left in silence. Twilight and Rarity even leant their own magical strength to the hardworking doctors, funneling extra strength to them so they didn't depete their reserves so quickly. Rarity even wound up exerting herself so heavily she passed out on two occasions, but she didn't stop.

After nearly a week of constant, heroic effort, the doctors had restored enough of Duran's nervous system for him to finally wake up. Blinking, he asked thickly, "Uh... what happened, 'n' where 'm I?"

Twilight and Applejack were on watch at the time, and the unicorn was too overcome with emotion to speak, so it fell to the orange earth pony to explain. She adjusted her hat (she'd gone back to wearing the rather battered one Rainbow Dash had returned) and told him, "Well, I don't rightly know all the specifics, but you had some kinda 'gen'ral nerve collapse,' or some-such. Yer back in the Ponyville hospital, been here fer 'bout a week."

The human asked for more specifics, but Applejack didn't know much else. One of the supporting doctors took pity on the farmpony and came over to explain. Duran listened intently to the doctor's description of the progressive neural collapse that had nearly killed him. When the medical pony was finished, the human looked down at his immobile metal arm, a strange smile spreading over his face. Twilight, Applejack, and the doctor looked at him with concern.

"Uh... you okay there?" Applejack asked.

He pointed at the prosthetic. "I kn- knew it wasn't a hardware problem! Blasted wetware." Duran managed to say. The ponies stared at him incredulously, before Twilight choked out a laugh.

The doctors kept Duran in the hospital for another week, working on further neural reconstruction, before he was released. Pinkie threw another party, holding it in the town square and inviting everypony. She planned it to combine a "thank you" party for the doctors' tireless work with a chance for everypony in town to meet the odd-looking alien in non-threatening circumstances. Duran was able to get out of the hospital on his own power, though his progress was painful to watch as he hobbled along, holding his crutch with his one working arm. Rainbow offered to carry him more than once, but he steadfastly refused. She hovered along beside him just in case, ready to catch him if he fell.

The party went well. It was the first time Duran had been able to talk to the six doctors who had saved his life, and he thanked all of them effusively. He swore to repay their generosity one day, though they all thanked him politely for the offer, privately thinking that nothing would come of it. The rest of the town had a chance to meet him too, though most simply congratulated him on his recovery, moving on after exchaging a few polite words. There were exceptions, of course. One mint-green unicorn with a harp cutie mark seemed oddly fascinated by the human's mannerisms, hanging around talking to him for most of the party. Rainbow Dash and Twilight Sparkle's friends stayed close by as well, especially Fluttershy, who was concerned about the human's still-fragile health. Rarity, who'd been told by Twilight about the human's seeming aversion to going about unclothed, (and being horrified by the state of his only article of clothing) presented him with several varieties of clothing she'd put together, trying to blend together the pony styles she was familiar with and what she'd seen of the human's fatigues.

Duran was touched, doubly so when the unicorn brushed aside the thought of payment. "It's a gift, dear." She explained, "Besides, it was a wonderful challenge! I'd never considered making anything in this shape before, I quite enjoyed seeing how the styles worked together!"

Afterward, Twilight offered to let the human stay at her library for as long as he wanted. Rainbow sheepishly confessed that she'd make the same offer, "Only, you know, my place is made of clouds. Kinda awkward for anyone who can't walk on 'em!"

Duran didn't wait long before finding his own place. Celestia offered him a royal stipend in exchange for finding a way to make the contents of the recovered library core available to the Royal Library, and Duran agreed quickly, having intended to do so anyway. Twilight was relieved, having looked at the plans he'd given her for an access point and realizing she couldn't make heads or tails of them. He set to with a will, demonstrating his own magical ability for the first time as he molded components out of base materials when he couldn't find all the stuff he needed. It took him a fair amount of effort to do so, however, and Fluttershy (who looked after the human when she got the chance) wouldn't let him do very much at one time. She made him promise her that he'd only do a small amount at once, and she got Twilight to promise to monitor him. Even with the restrictions, he was able to build a small power unit, screen, slightly oversized keyboard, and even a small adjustable device that would fit over a pony's hoof to help them type more effectively. Promising that he'd be able to build a large networked system for the Royal Library (and explaining what that actually was when nopony understood it) he bought a small home in Ponyville and converted a large portion of it into a workshop. His friends visited often, including the green unicorn named Lyra who'd gotten along with the large alien so well at Pinkie's big party, and a mysterious brown earth pony with an hourglass cutie mark, who always talked to Duran when nopony else was around. He was often working on machines or mechanisms when anypony came to visit, usually powered by odd arcane energy sources rather than the electricity used by the salvaged library core. Before long, the small robots he built were a ubiquitous sight, running off on one errand or another on behalf of their maker, some crawling along the ground while others flitted through the air.

It was shortly after Duran began building and using his little robots that Rainbow Dash had a minor mishap. She'd been hanging around the human as much as she could, though she had a lot of weather scheduling to catch up on when they got back. Still, she was pleased at how much he'd recovered; he'd given her a bad scare, and she was still checking in on him at odd times to make sure he was okay. This particular morning, she was planning on meeting a couple of new weatherworkers that had moved into town before going over to Duran's place. He'd been talking about going along to a Wonderbolts show in a nearby town, and she'd gotten her hooves on a list of times and places she was planning on sharing. First, though, she was showering up so she'd be presentable when she met the new members of her crew. She didn't realize something was wrong until she'd been standing under the spray for a moment, and caught the odd colors out of the corner of her eye. When she noticed what was going on, she leapt out of her shower, aghast, as she realized that somehow, the rainbow fountain outside her house was pouring through her showerhead. She toweled off quickly, but it was too late; her light blue coat was faintly stained in multicolored stripes to match her mane and tail. I look like a piece of candy, she thought, examining herself in the mirror. She facehooved, aw, man, this stuff's really hard to wash out! I'm gonna have to meet my new weatherworkers looking like this! She sighed. Better get it over with.

The meeting went pretty much as she'd expected. She'd been extra-serious and businesslike to try and make up for her slightly silly appearance, but though the two new pegasi (a pair of siblings, brother and sister, who'd just moved to Ponyville from Cloudsdale) were perfectly polite and serious, Rainbow could tell they were trying really hard not to snicker. She'd been headed to Rarity's boutique after her meeting, hoping the unicorn would have something to wash the concentrated rainbows out of her fur, when she walked by Duran and Twilight playing a board game on an outside table while Fluttershy watched. The human called out, "Hey, Dash? Scale of one to ten?"

She stopped, not understanding right away. "Uh, what?"

Twilight and Fluttershy were gaping at the (formerly) cyan pegasus, but Duran was trying to stifle a grin. "You know, the whole..." he mimed stripes with his fingers, "How would you rate it?"

She stared at him like he'd lost his mind, but then understanding dawned. "Wh- it was you?" she spluttered, "Bu- wha- ... how?"

He pursed his lips and let out an odd, twittering whistle. A pair of small machines swooped down to hover behind his shoulders. Another modulated whistle, and the machines each unfolded a jointed arm and waved at her. The human gave a beatific smile, but didn't say anything.

Rainbow glared for a second, but she couldn't manage to stay angry. It is kinda funny, she thought, as the first chuckle slipped out. Soon she was laughing, along with Duran, Twilight and Fluttershy. When she caught her breath, she shook a hoof at the human. "Oh, dude, it is so on now! And I give it an eight; I thought it was just an accident until just now, and for a nine or ten you really should know you've been pranked!"

That marked the resumption of Rainbow and Duran's prank war. Prank War Two had a lower tempo than the original had boasted, since both belligerants were busy with other projects, but it stretched out for far longer. Both sides eventually brought in allies; Rainbow enlisting Pinkie Pie, and Duran, oddly enough, gaining Rarity's support. The Pinkie/Rainbow Alliance found the Human/Unicorn League to be a formidable foe; both members combined creativity and attention to detail, and while the League set up far fewer pranks than the Alliance, those they did engage in tended to be the stuff of legends.

Rainbow actually found it difficult to make Duran look silly, as by that point he'd started to repay Rarity's generosity, in his own odd way. He'd begun distributing his arcane and mechanical technology, forming several corporations to better distribute the fruits of his labor, and he had a significant surplus of funds. He would periodically visit Rarity's boutique, and place an order for something absolutely rediculous. He always proclaimed total satisfaction with whatever bizzarre garb resulted, insisting on dramatically overpaying. This, on occasion, led to tension in the Human/Unicorn League (despite the name, Twilight remained a declared neutral party, as did Lyra) when Rarity felt that he was paying too much. He always snuck the surplus in somehow, though, and after Rarity woke up one night and went downstairs to find a horde of tiny robots making an artful mural out of newly-mined gemstones on the floor of one of her downstairs dressing stalls, she stopped arguing. It was easier that way.

His odd garments paid for, he would then wear the outlandish getups anytime he left Ponyville. The alien inventor had become quite well-known in Equestrian high society, and on the rare occasions he attended an out-of-town party, Rarity was often flooded with orders from high-class ponies for clothing similar to the human's frankly insane taste in high fashion. She wasn't sure whether to be flattered or infuriated; she knew he was making her famous, almost a household name amongst the upper-crust, but at the same time he was playing a gigantic joke on the Equestrian aristocracy. The fashion-conscious unicorn eventually persuaded the engineer to transition to more... conventional fashions, but it took her months to talk him into it. Twilight later told Rarity that Celestia had found the whole affair howlingly funny, and that the Princess had often found herself hard-pressed to keep from laughing at the clothing her courtiers wore after Duran had attended a society party. She'd even had Twilight warn her what days the engineer left Ponyville, so she could mark it on her calendar and prepare herself to not laugh at the things she'd see the next day or so.

The human paid back the doctors who had saved his life, as well. Any time his work, or his research into the library core, yielded a potential medical application, he funded its production out of his own resources, donating the results to every hospital in the Principality.

The advancements that resulted soon permeated every level of Equestrian society. Telecommunications networks, household appliances, mechanical conveyances, all this and more came flooding out of the workshop of the one-legged human.

Not every influence he had was positive, however. Rainbow Dash, following up on her thoughts during the fight around the portal, soon started to patrol the edge of the Everfree Forest, aided by a pair of armed flying robots she'd gotten Duran to build. Fluttershy was horrified, and the two pegasi had a serious fight over the matter. Relations between the two remained cool, especially when Rainbow began recruiting other, like-minded ponies to patrol similar wild areas in other areas of Equestria. Duran provided these teams with robots, and eventually also with armor and weapons of their own. When it was noticed, the human and the ponies he supported recieved serious negative press from the newly-established news outlets. His reputation was damaged, but far from destroyed. Academies sprung up across the Principality of Equestria, devoted to teaching young colts and fillies the ins and outs of the new technologies.

Yet, even as Duran's influence grew, his health weakened. The human never fully recovered from his collapse, and though periodic therapy slowed his deterioration, it was unable to halt it. He was as active as he could manage, but he stopped leaving Ponyville entirely after about six years. He lasted a further three, producing marvel after marvel from a workshop that seemed far too small, before dying quietly in his sleep.

His friends discovered his Will while clearing out his home. The first part detailed the distribution of his assets, and they discovered that he had been vastly more wealthy than anypony had known. He left each of his friends huge fortunes, dispersing the remainder to support the academies and a fund that would help provide newly developed medical technology to Equestrian hospitals at sharply reduced costs.

The second component was intended for his friends' eyes only. It read, "check the basement." and had an access code appended. They were all confused, until Pinkie Pie stumbled across a door hidden behind a bookcase. It led downward, to a sealed door with a keypad. A note stuck to the door read, "This is where I left the dangerous stuff. I trust you all to handle it, but be careful."

Inside was his real workshop. Hundreds of incomplete machines lay scattered about, with finished projects interspersed. They found weapons designs, potentially dangerous vehicles, a small army of armed robots that gave Twilight chills, a functional space drive, and finally, in a sealed vault, a complete working copy of the Tethinar Imperium's faster than light drive. They found a third note beside it. All it said was, "This will give you the stars, if you want them. Reach out, and marvel at what you may find."

As for what they did with all these things? Well, that's another story.


*Author's note: that's it, folks. Thanks for reading, and making it all the way to the end. Like my previous note said, please remember to leave a review!

Special thanks to firefossil, GBscientist, Harry Leferts, and Sixpack. Your input was greatly appreciated, folks!