“As kids we're not taught how to deal with success; we're taught how to deal with failure. If at first you don't succeed, try, try again. If at first you succeed, then what?”

Charlie Sheen

Spike looked up from his card game as the library doors opened. Twilight trudged in: her coat was covered in soot and ash, and patches of her mane and tail were singed and blackened. He opened his mouth to speak but kept quiet as she went directly to the bathroom.

Spike glanced at Owloysius before tossing his cards down and jumping to his feet. He ran to the bathroom door and pressed his ear against it.

“Twilight?” he said, “there was a letter while you were away. Not from the princess or anything: just a regular letter.”

He knocked on the door but there was no response. He tested the lever and found it unlocked. Spike glanced back at Owloysius, who looked up from his own cards just long enough to shrug.

“You in there, Twi?” he opened the door and saw Twilight in the middle of the room. Her mane was shorn down to a ragged, ugly brush cut and her tail was a stumpy bristle. The floor was covered with a vast quantity of long, purple hair, and there were a pair of garden shears on the counter.

Spike clenched both fists in panic. “Twilight! What are you—”

Too late, Spike saw the aura of a delicate spell taking shape around Twilight’s horn. She flinched at the sound of his voice, utterly distracted. A flash of light filled the bathroom and sent Spike tumbling backwards. He staggered to his feet and rubbed his eyes, and when his vision cleared Twilight Sparkle’s mane and coat were back to their usual length and lustre.

“I’m so sorry, Twi! I didn’t know you were casting a spell in there.”

“It’s all right,” she said, “but I’d appreciate it if you knocked next time.”

“I thought I did. I didn’t ruin the spell, did I? Did something go horribly wrong?”

“The spell worked fine,” said Twilight. “It takes a little more than that to distract me, and it was a very simple spell to begin with.”

Spike stared as she swept up the massive heap of purple hair. “Are you telling me that ‘growing’ magic is simple?”

“Once you get the hang of it, yes.” She dumped the discarded hair in a wastebasket. “Was there something you needed?”

“Yeah. A letter arrived while you were away.” Spike held up a scroll with a plain grey ribbon. “It wasn’t from the princess or anything, so it’s probably not important.”

“All letters are important,” said Twilight. “I’d better take care of this now.”

“But you just got back. You must be totally burnt out!” He glanced at a charred patch of hair hanging over the lip of the wastebasket. “I mean... you must be really tired.”

“Work is work, Spike. If somepony took the time to send me a letter then it must be important. I can’t just blow something off whenever I feel like it.” She unfolded her writing desk and prepared a fresh sheet of parchment. “The letter, Spike. If you please.”

Spike frowned, but opened the scroll and cleared his throat.

“Dear Twilight Sparkle. The Canterlot Association of Royal Regulatory Ordinances, Terms and Stipulations appreciates your interest in assisting with the...” he paused and scanned ahead. “...thanks you for your investment of time and effort... due to unforeseen circumstances, we regret to inform you... your services will not be required.”

Twilight twisted around in her chair to look at him. “Are they talking about the convention?”

“It, uh... looks like.” Spike scanned the scroll. “It says here the person who volunteered to host the convention decided to take a vacation ‘because they felt like it,’ and they didn’t give any advance notice. The association couldn’t find a new venue in time so they decided to cancel the whole thing.”

“But I was supposed to give a presentation. I was... I was supposed to run a panel.” Twilight looked back at her desk. “I’ve been working for weeks! I skipped two of Pinkie Pie’s tasty pastry tasting parties for this.”

Spike rolled up the scroll until it was clenched tight. He watched her from behind as she bowed her head, shoulders shaking. “Geez, Twi. I’m sure they—”

Twilight jumped up on her chair and reared up, tossing her head back with laughter. “This is wonderful! I wasted two weeks getting ready for that horrible chore, and now I’m free! Free at last!” She leapt down and began dancing about the room, laughing all the while. Spike yelped as she scooped him up and swung him in a circle.

“So, this is a good thing?”

“Are you kidding? That convention is one whole week of boring lectures and annoying questions! It takes two whole days just to fill out the invitation paperwork!” She set him down and ran to the wall calendar. She grabbed a quill and ran a bright red stroke across an entire row of squares, each filled with tiny little notes. “I have a whole week to do whatever I want!”

“Really? Anything at all?”

“Oh, yes. And I know exactly what I’m doing for starters.” Her horn glowed, and an entire chemistry set flew off the shelves and arranged itself on a table. “There’s something I’ve been putting off for far too long—something absolutely essential—and this is the perfect opportunity to do a proper job of it.”

Spike watched as she reared up and performed a pirouette. He wrung his hands as the beakers and vials began to bubble and boil.

Spike scanned the checklist he’d been given and examined the row of bubbling vials. All right Spike. It’s very simple chemistry. As long as you stick to the list, nothing will go wrong. It’s a total no-brainer. He reached out and picked up a vial, and the searing heat was nothing at all to his tiny talons. He held the vial over a mixing bowl and carefully—

“Hiya, Spike!” Pinkie Pie called as she burst through the front door.

“Ahh!” Spike fumbled the vial and dumped the contents all at once. The mixture bubbled over the edge of the bowl and exploded violently. A thick layer of soapy foam covered Spike from head to toe and spattered most of the tabletop.

“I didn’t interrupt anything, did I?” Pinkie Pie said, “Twilight’s always saying that this is a public library so there’s no need to knock first.”

“Nah, it’s okay. I should have been more careful anyways.” Spike wiped the foam off his face. “A no-brainer, she says. Impossible to mess up, she says... I don’t know how she does it.”

Pinkie Pie walked inside and looked at the apparatus on the table. “Well, that’s why she’s the ‘Celestia’s most faithful student.’ She knows what she’s doing!”

“Yeah, but it isn’t nearly as easy as she makes it out to be. Her spells almost never go wrong.” He began mixing the remaining vials, this time gradually. “At least the whole batch wasn’t spoiled. There should be just enough.”

“Enough of what? And what for?” Pinkie Pie bounced in place. “Can I guess? Can I have twenty questions, first?”

“Absolutely not. Twilight’s finally gotten some time to herself and she isn’t to be disturbed for anything.”

“Wow,” Pinkie said, “is she doing something important for the princess?”

“She’s doing something important for herself. She just had an entire week free up and she’s got a whole stack of personal projects to take care of. She’s been putting some of them off ever since she graduated.”

“Twilight...? Has free time? I totally have to throw a party for her!” She glanced about the library. “What would she like the best? I know: a book club reading! Or maybe a workshop on how to write essays!”

“That’s not really—” Spike stroked his chin. “Actually, she’d love that. But it’ll just have to wait.”

“She won’t be busy the whole week, will she?”

“Probably not. She mentioned wanting to hang out with all her friends, but she has to take care of the most important thing first. And trust me... it’s going to take the entire day.”

“That’s all right,” said Pinkie Pie, “I totally understand. I’ll check back tomorrow!”

“Laters,” said Spike. He watched her leave, then turned to the thick layer of bubbly suds. He sighed and went to the broom closet to fetch a mop.

Spike knocked on the bathroom door.

“Whozits?” Twilight answered from beyond. Her voice was slurred.

“It’s me. I know you said you didn’t want to be disturbed unless a letter from the Princess arrived.” Spike looked at the gilded red-ribboned scroll in his hand. “So... yeah. That’s what happened. Should I just leave it by the door?”

“You can come in. Just be quiet, if you please.”

Spike opened the door and stepped into the dark bathroom. There were over a dozen candles arranged about the room, casting warm light and wobbly shadows on the walls. The air was filled with scented smoke and the sound of lapping water.

Spike went to the bathtub and climbed up a nearby step-stool. Twilight Sparkle was buried under a blanket of snow-white bubbles. She was wearing a frilly pink blindfold and leaning her head against the edge of the tub.

Spike opened his mouth to speak, but a hollow wooden clink interrupted him. He looked at the little bamboo water fountain sitting on the countertop: a stream of water dribbled out of a tiny glowing portal and began refilling the hollow shaft of the lever.

He held up the scroll. “Message from the princess. Should I leave it on the counter?”

“S’okay. Gimme.”

“You’re not going to get it wet, are you?”

“S’fine.”

Spike frowned at her. “You know what happens when you read in the tub.”

“S’fine, really. My friends and I just finished a dangerous expedition for the crown. She’s probably just checking up on us.”

Spike held up the scroll and watched nervously as it levitated over the tub.

“Thanks,” she said.

“So, will you—” Spike spun around and glared at the bamboo fountain.

The lever of the bamboo fountain dropped down, clinking against the frame and spilling its contents into the sink.

Spike turned back to Twilight. “Will you need anything else, then?”

“Nope.”

“Well okay then. If you’re sure.”

Spike left the bathroom, taking care to close the door quietly.

The bathroom door burst open, and Spike dropped his mop in surprise. Twilight stood in the open doorway, dripping wet and covered with suds. She gasped for breath, eyes wide.

“Can’t say I didn’t warn you,” said Spike. “You know what happens when you read in the tub.”

“I didn’t—!” Twilight shook her head. “Just go to the basement and start unpacking things. We need to set up the thaumaturgical apparatus!”

“We’ve got a ton of those. Which do you mean?” Spike ticked off his talons. “The toxicological arcano-analyzer? The clinical transmutation recombinator array? The hermetic quasi-dimensional solenoid? Or the spelly-welly thingy-wingy?”

“Yes! All of it! Everything!”

Spike watched her gallop through the main hall, trailing soap and water. He held up his mop. “Do you want me to—”

“There’s no time for tidying up! This is an emergency!”

Spike stared at her in shock. He dropped the mop and sprinted to the basement.

Rarity and Pinkie Pie walked down Ponyville’s busy main street and towards the massive tree-house that was plainly visible from any part of the road.

“If you ask me,” Rarity said, “she’s been in desperate need of a vacation for months. The least we can do is give her some time to herself.”

“I guess so,” Pinkie Pie said, “but I don’t think she really knows much about having fun. I’ve done everything I can to mentor her since she arrived but she still hasn’t gotten the hang of it yet... not quite. Shouldn’t we help her relax?”

“I’m sure she’d love to spend more time with us, but she also loves being a scholar. Working for the princess must be very fulfilling, but it’ll be a nice change of pace for her to work on a project of her own.”

“But it’s still work, isn’t it? What’s the difference?”

“I’ve been paid to make dresses for hundreds of other ponies, and I assure you it’s nothing like creating a work of art for its own sake. No requirements, no deadlines, no budgets... just you and the pure bliss of creativity.” Rarity tossed her mane aside. “It may seem like a lot of paperwork to us. But to her, it’s satisfying. Do you understand?”

“Yeah,” she said. “I mean... no, I don’t. Not really. But you’re probably right.”

“There you go,” said Rarity. She went to the front door of the library and set her hoof on the handle. “Now remember. No matter what we see in there, we need to let her know that we respect her wishes. This is her time off and we can trust her to spend it however she likes.

“Right,” Pinkie Pie said, “we’re only here to encourage her. We’re not going to judge her hobby, and we’re definitely not going to drag her off to a party.”

“Exactly,” said Rarity.

Pinkie Pie took a deep breath and opened the door.

“Hi, Twilight! We just... wanted... to...”

Rarity walked in and stood beside her. She glanced at Pinkie Pie’s stunned expression before looking at the interior of the library itself: The bookshelves were covered with waterproof tarps and several folding tables had been arranged in a circle. The upper sections of the walls were covered with huge chalkboards—packed with dense scribbles and diagrams—and the floor was carpeted with scrolls and torn paper. Over a dozen large mechanical devices whirred and hummed, and thick bundles of colored cables snaked across the floor and down into the basement. A single massive device dominated the center of the library: a tall metal pillar that bristled with glowing tubes, sparking antennae and rattling gauges.

Pinkie Pie and Rarity stared at the machinery, spellbound. Spike scrambled past with a towering armload of books. “Sorry, guys. The library’s closed.”

They stared at the door they’d just opened, only then noticing the “closed” sign hanging on the front.

Pinkie Pie tilted her head in awe. “I’ve never seen that sign before!”

“We’ve never used it before.” Spike set down one stack of books and scooped up another. “Sorry, Rare. Kinda busy here.”

Pinkie Pie leaned over and whispered to Rarity. “Is this really Twilight’s idea of fun?”

“It’s... possible.” Rarity raised her voice and called to spike. “Can we speak to Twilight, please?”

“Look, I’d—”

“Spike!” Twilight called. They looked up and saw her hanging from the ceiling by a series of cables, busily manipulating part of the central machinery. She was wearing a set of thick, black-lensed goggles. “Recalibrate the omni-tronic un-quantum resonator for four and a half spectroniums. Not four. Not five. Four and a half!”

“Sure thing, boss!” Spike said. He looked over his shoulder as he ran away. “Sorry, girls. Might want to check back later!”

They watched as portions of the central machine rotated, slowly picking up speed. Twilight kicked away from the machine and swung around the room in a wide arc, coming to a halt as she grabbed onto a different part of the central mechanism.

“That sort of looks like fun,” Pinkie Pie said. “Do you think it’s a game? Or something?”

“Well, I doubt it’s—”

“Spike!” Twilight shouted, “hurry up with the calibration! This isn’t a game or something!”

“Sorry boss! Almost done!”

Pinkie Pie gave Rarity a displeased squint.

“Give us a minute,” Rarity said, “I’m sure she has an excellent reason for all this. I’m sure it’s very important... very serious.”

Pinkie Pie glowered up at Twilight. “That’s what I’m worried about.”

Rarity pushed her outside and locked the door behind her. She strolled closer to the pillar of machinery and craned her neck to look up. “Twilight? Dear? Can we talk for just a moment?”

“Can’t! Busy! No distractions! This is important!”

“More important than your friends? Surely you—” Rarity flinched aside as a nearby machine sprang to life, spinning and whirring. “Surely you can spare a moment?”

“I can, but not right now. Just give me one more minute and I’ll explain everything!”

“Ah, well of course.” Rarity backed away from the nearest table. “I’ll just wait over here.”

“No!” Twilight shouted. “Not by the electropomorphic condensification coils!”

Rarity flinched away from a nearby device. “Goodness! Is it dangerous?”

“Not if you’re wearing rubber-soled horseshoes.”

Rarity shuffled sideways. “How about—”

“Now you’re too close to the sinusoidal centripetal centrifuge! It could injure you if it got caught in your mane or tail!”

Rarity gasped and retreated from the rapidly spinning wheel. She bumped up against a covered bookshelf and shuffled sideways until none of the devices were in reach.

“How about here? Is here good?”

“By the young adult paperbacks? Blech! You wouldn’t believe the drivel we have now. I’ve been trying to replace it for months but all the best series are way too expensive. Small town libraries get hardly any funding, and donations have been pretty poor this month.”

The hum from the mechanical pillar grew louder and a series of long antennae spread out from the middle, crackling with energy.

Twilight swung around and lowered herself to the floor. “Maybe it’s time we held a fundraiser. A bake sale, maybe. Something the school fillies could help with.”

“I see,” Rarity said. “Maybe it’d be best if I just waited outside.”

“Sorry Rarity, but I can’t allow that.” Twilight Sparkle adjusted her goggles and levitated a cutting torch. “It’s just not safe in here. I’ll have to ask you to wait outside.”

“Yes, of course. Quite so.”

Rarity waited on the front step of the library and politely turned away the few ponies who approached. Massive shafts of light cascaded out of every window. A deep rumbling echoed across the village. She glanced every back now and then, but couldn’t bring herself to open the door.

Rarity flinched as the pyrotechnic display came to an abrupt halt. She reached for the door, hesitant, but Twilight opened it from inside.

“Could you help me with something? Just quick?”

“With...” Rarity’s eyes flicked between Twilight and machinery beyond. “...What?”

Twilight rushed inside. Rarity followed and glanced around. The machinery was idle. The library was quiet.

“Here,” Twilight said and opened a compartment in the central mechanism. She carefully removed a teapot and poured the contents into a nearby cup. “Try some. Tell me what you think.”

Rarity bit her lip. “What is it?”

“I’m not sure yet. I need a second opinion.”

Rarity’s horn glowed and the cup and saucer levitated close. She sniffed the liquid and gave Twilight one last hesitant look.

“Go on,” she said. “I’ve already tried some. It’s perfectly safe.”

Rarity took a small sip and delicately smacked her lips. “Hm.”

“What do you think? Be totally honest.”

“Lemon jasmine green-tea, I think. Not bad.” She peered into the cup and swirled the steaming liquid. “Not the best, mind you. It needs a little more fragrance.”

“Argh!” Twilight tossed her head and stomped away.

“No wait!” Rarity set the cup aside and chased after her. “It’s not that bad, really! You just need to find the right blend of citrus, that’s all!”

“It’s not the tea I’m worried about!” Twilight rolled her eyes and pointed at the monolithic mechanism. “I wouldn’t go to all this trouble just to cast a ‘brew-some-tea’ spell. This is way more important!”

“I think you need to start from the beginning.” Rarity’s horn glowed and a pair of seat cushions drifted to the floor beside them. A small end-table landed between them, with the teapot neatly arranged on a tray. “You promised to explain everything if I waited. And I did wait.”

Twilight flopped back on her cushion and poured a second cup of tea. “Princess Celestia has asked me to develop a new spell. Of sorts. I need to do a very thorough job of it, and it needs to be absolutely, positively fail-proof.”

“My goodness!” said Rarity. “That does sound like quite the undertaking. But I’m sure somepony as gifted as you should have no trouble at all. I can’t think of anypony better suited to the task.”

“I’ve already finished a prototype of the spell, but I can’t...” Twilight's shoulders slumped. “Well, you see...”

“You can’t what? You can tell me. Really.”

“I can’t test it.”

Rarity’s set her cup aside. “But you never have trouble casting spells!”

“I can cast it just fine. I just can’t test it.”

“I’m not sure I understand. If you can cast it, surely you’ll know whether it worked or not. Shouldn’t it be obvious?”

Twilight levitated a gilded scroll to Rarity. The seal on the red ribbon had been broken and rewrapped. “Maybe you should just read the letter. It’ll explain everything.”

“If you’re sure.” Rarity slipped off the ribbon and unfurled the scroll, clearing her throat. “From the desk of Princess Celestia. Dear Twilight Sparkle, my most faithful student: I am pleased to hear of your safe return to Ponyville, and wish you a swift recovery. However, there is a matter of no small—”

“What are you doing?”

“Hm? Well, I’m reading the letter of course.”

“Why out loud?” said Twilight. “I’ve already read it, and there’s nopony else here.”

“Oh. Well, I suppose so.”

Rarity’s eyes moved back and forth as she scanned the letter. She pursed her lips now and then, and eventually unfurled the lower half of the scroll. The faint sound of birdsong drifted in through a nearby window.

Rarity lowered the scroll with a gasp. “Oh, my! That is quite a conundrum! I can see why you—and yet it’s—but how would that even work?”

“See what I mean?” Twilight said and rolled up the scroll. “It’s not difficult. It’s just troublesome. I’ve tried everything I can think of, and nothing’s working.”

“It’s not even all that complicated, is it? It’s just puzzling.”

“Exactly! The spell itself is so simple that a filly could cast it. But the spell itself isn’t the problem. You’re a unicorn, Rarity. I know you’re not an expert on hard theory, but if there’s anything you can think of... anything at all!”

“Hm...” Rarity leaned her head back and gazed idly upward. “Have you tried...?”

Next Chapter: %i%: Non-deterministic problems... won’t. Polynomial-time problems... can’t. Estimated time remaining: 9 Hours, 30 Minutes