//------------------------------//
// Chapter 28: Infinite Solution Space 
// Story: Harry Potter and the Prancing of Ponies 
// by The Guy Who Writes 
//------------------------------//

Angle of Attack #1: Figure out the Stone of Permanence. 

Unfortunately, this was the only angle available to him. If it didn't work out, he'd have to go to number two: Escape the Mirror.

Mr. Book claimed, in Parseltongue, to know of a ritual that would work for resurrection, but only on the other side due to the required sacrifices.

Once Mr. Silver stated his intentions to figure out the stone, Mr. Book had him sign a magical contract. A carefully written magical contract, to the effect that Silver would take no risks, great or small, to the destruction of the world. Another clause of the contract stated that Silver would take an Unbreakable Vow about the matter if Mr. Book arranged for it to be done before the contract expired.

Mr. Book, sounding annoyed, said that he should have done this earlier, but he had been banking on the Vow being more easily solved, more translatable to ponies. Unfortunately, he suspected that crossed horns, like crossed wands, would be needed for the Vow to take. You probably couldn't cross a wand with a horn and still have it work. This contract was a temporary resort until he found a workaround. 

That done, Mr. Book said that he did not mind Mr. Silver running his own tests on the stone, but a series of Parseltongue promises ensured that Mr. Silver wouldn't use any reckless, damaging, or dangerous magic in his research. He would only use Transfiguration, and never with the stone itself as a target, unless given express permission by Mr. Book to do otherwise. He would also try no strange Transfigurations. This was not Transfiguration research. It was stone research. Standard target forms only, like glass marbles. So long as he followed those rules, he would be free to experiment as he pleased, and he would not need the standard Transfiguration research precautions.

Mr. Book had already tried his own experiments, of course, but not in a way Silver had expected. Silver had expected that Mr. Book had been constantly trying ideas, like he would have been.

He was annoyed to learn that Mr. Book only rarely tried to solve the stone. He put the problem on the backburner, letting ideas simmer, occasionally trying when something sufficiently new sprang to mind. If he forced himself to try more often than that, he would have grown resentful, and possibly written the whole thing off as a bad job. A false stone. An impossible problem. Et cetera. Mr. Book knew his mind well enough to know how to avoid senseless frustration. He claims that if he thought his immortality relied on the stone, he almost certainly would have solved it by now, if it was solvable. If Mr. Silver was similarly motivated, perhaps he would find success.

Silver dismissed his own frustration as irrelevant to his current goals. He hoped his future self would remember to have a conversation with Mr. Book about letting him participate in the future. Instead, he asked what Mr. Book had already tried.

Silver didn't understand all the ideas Mr. Book says he tested, but he tried his best to remember them anyway, just so he wouldn't waste time by doing repeat experiments.

He also managed to extract a Parseltongue promise from Mr. Book that they would share the stone if he figured it out, or helped Mr. Book figure it out.

Mr. Book, in return, managed to extract the promise from Silver that they would share its free use only with each other, no others, unless Silver also figured out how to make another stone, in which case Silver could use his own stone as he pleased, so long as it didn't threaten the world.

Silver knew he would get nothing more, and if he tried to push it, Mr. Book would just take the stone and only ever use it how he saw fit.

After all the housekeeping was done, he got to work.

Silver tried new ideas as they came to him.

Holding the stone in various ways. Placing it on all parts of his body as he performed a transfiguration. Placing it near the object being transfigured in various orientations. Placing it on the object. Placing it under the object. Placing it in an object, a transfigured hollow ball.

Mr. Book left at this point, probably out of boredom.

At some point, Silver suspected the stone might only make gold transfigurations and living transfigurations permanent.

The lump of gold did not last, falsifying the theory.

Maybe just living transfigurations, and the gold thing was a lie?

The ant, transfigured from a captured beetle, died of transfiguration sickness, falsifying the theory.

Maybe living transfigurations had to be minor variations on the same species?

The queen ant, transfigured from an ordinary worker, died of transfiguration sickness, falsifying the theory.

He tried many other small variations on this idea, but eventually decided to move on.

Maybe the alchemy thing wasn't a complete lie? Maybe the stone of permanence did need alchemy to activate, even if the part about it being created through alchemy was a lie.

Mr. Book, summoned by Mahasu, agreed this was worth testing, but found no success in any of the alchemical formulae he knew. Silver didn't know any alchemy himself, so he went back to the drawing board.

He worked for hours.

Then days.

Then possibly weeks.

He didn't know how much time passed.

He lost track of how many failed ideas he went through. Hundreds, certainly. Thousands, probably. If he counted all the ideas he thought of, including the ones he discarded without testing, he was probably well past ten thousand.

With a phoenix on his shoulder, he did not collapse from exhaustion. He didn't sleep. He didn't even leave the cave but once. He went out to buy a massive bulk order of ordinary hay and a large cup that could be refilled with Aguamenti, then it was straight back to work.

The maddening, the truly insanity-inducing part was, when he thought of a promising idea, he made sure to thoroughly falsify it by trying multiple small variations to see if they made a difference. Stone orientation was just one aspect. It could be that whatever you have to do, you have to do it for five minutes before it works.

Like flying laps, trying a bunch of small variations on the same idea was potentially necessary, but very mind-numbing.

Eventually, when he was sufficiently frustrated with the stone, he asked himself if there was anything he could do to speed up the testing itself. Better falsification methods. Ways to eliminate ideas faster. Streamlining the process. Efficiency.

On that note, he realised that if his transfigurations reverted quickly on their own, he wouldn't have to waste time/magic using finite.

He didn't care to solve this problem by himself.

Once he explained his envy for efficiency, Mr. Book taught him how to push sustaining magic out of a transfiguration by touch alone. After that, he also taught Silver how to use a miniscule amount of magic for each transfiguration. Ordinarily, less magic meant transfigurations would only last minutes. For the purposes of his experiments, less sustaining magic meant less time to drain that magic away again, and less effort wasted on each attempt.

Soon after, Silver finally found his ambidexterity advantage. When he wanted a spell to be as weak as possible, his left hoof worked wonders. He gained much practice with ambidextrous transfiguration as he worked.

After that, it was right back to testing.

Back to falsifying.

Back to getting the wrong answer.

Over.

And over.

And over.

And over.

And over.

And over.

And over.

And over.

And over.

And over again.

Long stretches of testing sessions were separated only by bathroom/food breaks, and the occasional visit from his mentor.

Mr. Book would sometimes ask him about what he'd tried. He'd sometimes get ideas of his own based on Silver's ideas. He'd sometimes try them. He, like Silver, never succeeded. He, unlike Silver, left the hideout after his failures, leaving Silver to continue testing alone.

Silver desperately wished there could be some trick to it. Right now, he felt like he was trying to aim a spell at an invisible enemy. He didn't feel like he was solving a puzzle like a scientist. He felt like he was trying a bunch of 'things with wings', instead of building a wind tunnel to measure lift.

But he didn't see anything else he could do, other than let his creativity run wild, then reign in that creativity with practical, real-world attempts.

He wishes he could have solved the problem in what cryptographers would call a 'brute force' manner. If a password is four numbers long, and you can try to solve it as many times as you want, one way to gain unauthorized entry is to start with 0000, then try 0001, then keep going all the way to 9999 until something finally works. It's the kind of puzzle-solving method that he tried to cheat with the Time Turner, his first Thursday of the school year, when he got the experimental result of 'DO NOT MESS WITH TIME'.

Unfortunately, even if that cheat had worked, he wouldn't have been able to use it here. There wasn't any systemic way of testing stone solutions. He wasn't pulling answers from a bounded solution space. There were no constraints. The answer could be literally anything involving the stone, according to Mr. Book. The stone was old enough that the answer could be truly eldritch.

So that meant the 'try everything' approach was the only way the stone would be solved, now that Perenelle is dead and can't give them the answer.

After three particularly grueling sessions of small variations, Silver threw up his hooves in frustration, reminded himself that a sixteen/seventeen-year-old girl could do it and it could be done many times in a single night, so it couldn't be that complicated or time-consuming. He asked himself if there were any extremely simple things he hadn't tried yet.

Three ideas came to mind.

He did not slap his face with his forehoof. If he'd done that every time he'd thought of an obvious idea that felt slightly promising, he'd have brain damage by now. He just jumped right in, expecting failure like all the others. He was already prepared to keep thinking as soon as each transfiguration reverted. He was already continuing to think, even as he took the first step to trying idea number one. 

"Mahasu." Pause. "Got something I want to try. Does polyjuice work on ponies, and if so, can you make some?"

"I already have, and it does. What do you wish to test?"

Idea number one is that maybe the stone only makes specific kinds of human/pony transfiguration permanent. Animagi. Metamorphmagi. Polyjuice. Whatever human transfiguration spells Perenelle used to maintain her youth and transform into Nicholas Flamel.

Mr. Book said that he did not think this would work. But, he sighed, the idea was just barely worth the valuable bottle of blank polyjuice and the effort it would take kidnap a disposable pony-

"NO!"/"CAW!"

-pay a financially struggling pony 3,000 of Mr. Silver's bits to "participate in a potentially dangerous experiment on short-term memory loss", then say "Somnium", then snip a bit of her hair for a reverse polyjuice in case this worked, then transform the volunteer while the stone was touching her body (it didn't work), then attempt to use the stone in other ways, then experience further failure, then wait for the polyjuice to wear off, then say "Obliviate," then return the pony whence she'd been taken, and did he have any other ideas, or should Mr. Book take his leave now?

"Two more. Mildly promising. Stay and watch if you want. Shouldn't take long."

Second idea: He held the stone in his hoof such that it was contacting the side of his wand as he performed the transfiguration.

Mr. Book, who stood behind him and watched, presumably with detached interest, teleported directly to his side, causing Silver to jump.

"Hey!"

Mr. Book ignored Silver's protest and picked up the glass marble. Mr. Book's eyebrows rose. He aimed his wand.

"Finite Incantatum."

...

Nothing happened.

...

Nothing had happened.

...

Nothing had happened.

Mr. Book replicated the result with a few separate transfigurations. The stone, staying in contact with his wand the entire time, made them all permanent.







"It would seem," said Mr. Book, "you have found the answer. I cannot believe I overlooked that possibility."

Silver wondered if Mr. Book's wandless abilities had actually prevented him from figuring it out, in this case.

Mr. Book sighed. "Nonetheless, well done, Mr. Silver."

"It's always easy to say an answer was obvious in retrospect," said Silver, not quite collapsing in exhaustion. Philomena was still on his back. "But even the easiest answers can be hard to see when you have to pull them from an infinite solution space."

"Hmm," said Mr. Book, seeming quite absorbed in the minor tests he was running now that he knew the answer.

Silver took the tungsten band off his back hoof.

"What next?"

"Iss time to ressurrect her. No trickss or deception on my part. Sshall do my honesst besst to bring her back to full and lassting life, nor do I intend or expect to ever harm her after. But first, you will repeat your Parseltongue promises not to tell Ms. Memory certain things upon her revival."

This had been established long ago.

It had been a trade.

Mr. Silver was allowed to nag Mr. Book about the progress he was making at the end of every tutoring session, but Mr. Silver would first have to promise not to tell Hermione, or anyone else, that (a) Mr. Book was Voldemort, (b) Mr. Book was Voldemort, or (c) Mr. Book was Voldemort.

Silver repeated that promise now.

"Sshall not tell girl-child-friend or anyone elsse of Dark Lord part of your identity. Sshall not hint. Sshall not joke. Sshall lie, hide truth ass much ass posssible, unlesss you give me leave to do otherwisse. Have no intention of breaking or bending thiss promisse."

He would at least be allowed to tell her about David Monroe, and about the fact that Mr. Book had saved the world at least once. The muggle world, at that. It might make the whole 'Voldemort' thing easier to accept once it did inevitably come out, some day in their eternity. And if he accomplishes his other ambition, it would be even easier.

"Good," said Mr. Book in response to his vocalised promise. "Follow."

Silver followed Mr. Book through one of the three tunnels that led away from the intersection within the crystal caverns they called their hideout. Not ten feet down the tunnel, they made a right turn into a descending staircase that did not match the surrounding 'natural' cave structures.

The clearly artificial staircase descended down into a cavernous cavity which did seem natural. There was the sound of dripping water, the smell of cold, damp stone, the sight of stalactites hanging from the ceiling and stalagmites growing from the ground around the room's rounded central space.

An altar stood exactly in the middle, surrounded by six obelisks.

"Place her form on that stone. Undo the transfiguration without finite."

Thanks to his desire for efficiency, he could now both sustain and undo a transfiguration through touch alone, without further use of his wand.

When he commanded his sustaining magic to drain away, he nearly jumped at what he saw on the altar.

"Hm," said Mr. Book. "I do not know why, but I was expecting her to be a unicorn, not another pegasus."

Silver had been expecting her to still be human.

Mr. Book took out his wand. "Stand back."

After a chant about hidden flesh – the stone of permanence contacting his wand as he performed the ritual – the back legs of the chestnut brown pony were restored. Silver didn't know if the obelisks echoing the chant in a different language were necessary to the ritual, or if Mr. Book was deliberately making this as creepy as possible. But the most likely answer was that, like using a wand, it simply made things easier for his mentor, even if he could have done without them. 

After the chant, and after Mr. Book marveled at her fixed form, he said aloud that an electric shock might suffice to restart her heart from there-

"CAW!"

-but Silver, inspired by Philomena, interposed with a different idea.

"Expecto PATRONUM!"







Mr. Silver's guess was correct. His Patronus had worked. Ms. Memory was back. And Mr. Silver was gone. Completely gone. His wand lay on the ground.

Perhaps the phoenix had taken him somewhere else, as it was wont to do since it wasn't his. Given Mr. Silver's desires, he would likely return as soon as possible.

Mr. Book set to work in the meantime, preparing the next ritual and its sacrifices. This would, hopefully, ensure all this hard work is never wasted.

First would come the mountain troll, then the unicorn. A true unicorn, which he'd worn as a false tooth at the time he'd been trapped, same as the troll. Thanks to his vow, he was forced to check for sapience first, just in case the mirror had bestowed it upon the two previously non-sapient creatures.

It had not, and he proceeded as planned.

But first, he used a different ritual to clone the creatures. Permanently clone them. He was beginning to enjoy this convenience.

He transfigured the originals back into false teeth, then began an ancient, lost, and therefore nameless ritual. He personally called it the 'Fusion' ritual.

The troll went off without a hitch. A simple cutting curse confirmed it had worked.

But to his utter bafflement, as soon as the second ritual took hold, as soon as the young female pegasus had been infused with the magical natures of both mountain troll and true unicorn, she too disappeared.

He was immediately put on high alert. He cast many security charms, and when those failed to turn up anything anomalous he used a near-international portkey to move himself to a safe place.

What was going on?