Disclaimer: I do not own the Fate franchise it belongs to Kinoko Nasu and Type-Moon.

Transposition

Chapter 20

Caster stepped into the large, empty room, and slid the doors behind her closed. She raised her hands, magic circles flashing into life around her. Pressing them in sequence, each circle vanished as Caster touched it, bounded fields falling into place around the room. Each had their own unique effect: one kept people from just walking into or even wondering about what was going on inside the room, another kept sights, sounds, and smells among other things that could be physically sensed from coming out, another prevented other magi from using magic to look into the room, while another disrupted magical communication from coming and going to and from the room, among other effects.

That done, Caster moved her hand horizontally through the air in front of her, the air shimmering before ten sword-shaped constructs of golden light flickered into existence. Caster nodded, and then made another gesture.

A large magic circle appeared revolving on the ceiling, and out fell one of the chimeras that had attacked her temple last night. It had tried to pounce on her from the flank, but Caster had intercepted it mid-jump, and imprisoned it within a pocket dimension until now.

The chimera fell hard and tumbled away before rolling onto its feet. It sniffed at the air a couple of times, and then turning to Caster snarled with hostility. Caster smiled with amusement at the sight and sound. "Down, boy." She said mockingly, and the chimera roared before charging at her.

Caster scoffed and gestured, the ten glowing constructs fanning out and then driving forward at a thought. Six stabbed through one each of the chimera's six legs, while another stabbed into its spiked, reptilian tail. Two stabbed into its body from the back, and the last through it snout. The glowing constructs did not cause physical damage, but despite that they still paralyzed the chimera and pinned it in place.

For the most part: the creature couldn't move its legs or tail, or move or open its snout and head, and its torso muscles were unresponsive but even so it shuddered and heaved as best it could in a vain struggle to break free.

"Much better," Caster remarked as she stepped forward, reaching up to pull down her hood to expose her beautiful, elfin-eared features. A gloved hand lazily ran through silken, violet hair in a theatrical gesture, and Caster smiled smugly as the chimera's golden eyes focused hatefully on her. "Sorry to say, but I can't really have you going on rampage until I figure out what you are."

Caster paused at that, theatrically drawing back and tapping a finger against her cheek. "No," she said. "That's not quite right. You see, I know what you are already."

Caster sighed, and her face took an expression of veiled disgust. "Chimera," she said. "That's what you are. Honestly, of all things the magi of this dull age could have remembered from ancient times, they just had to remember how to make chimera. Disgusting creatures…"

The last was emphasized with a flicker of lightning from Caster's hand, and which briefly washed over the chimera's form. To Caster's surprise, the chimera didn't respond with pain, though the reaction might have passed for it. But Caster's perceptions were not limited to the five senses, and her eyes widened as she sensed the lightning – a fairly basic mystery not just for her but even for modern magi – absorbed by the chimera, the mystery collapsing and the prana which sustained it added to the chimera's own life force.

This served to invigorate the creature, which struggled harder until Caster fed more power to her restraints. Narrowing her eyes, Caster studied her data closely, and her eyes widened and then narrowed again at what she saw.

"Interesting," she said softly. "The mysteries which made you are surprisingly profound, with around five hundred years of accumulated history behind them. You're not even a year old, but the mysteries behind you…"

Caster trailed off, shaking her head at the thought of the chimera's mysteries trying to adapt to and break the restraints Caster had placed on the beast. "They should hold though," Caster thought. "Long enough for me to figure out what makes this thing work. Still, it wouldn't do to be careless now, would it?"

Holding out her hands, Caster began murmuring in Greek while a magic circle flashed into life between her hands. As she finished her chant, the magic circle glowed brightly and then turned into two semi-circular bands of light. A gesture, and they flew forward to affix themselves around the chimera's neck, and collaring it. A word from Caster, and they dulled, if staying in place.

In the event the restraints broke, the collar would behead the chimera automatically.

"Let us begin then," Caster said. Walking over to a nearby table, she picked up a stylus and pressed a finger against the tip while placing a hand over a neat stack of paper. They glowed, and as Caster let go, the stylus floated down on its own and placed itself against the top sheet, ready to write and record her words.

Nodding once, Caster took the other tools laid out on the table, and generating a wire-framed shield around herself to keep splatter away, approached the chimera. "Now then," she said, beginning to cut into the chimera. "To start with, let's see what animal and which Phantasmal Beast sired and bore you either way. And from there, we'll see."

Caster smiled as the creature struggled, blood spurting and splattering against her shield, and sensed it finally begin to hurt.

A very good start then, to something that can keep me busy until Souichirou-sama returns this evening.

"Chimeras?" Shirou echoed in surprise and alarm.

Sakura nodded. Once again, the two of them were on the roof, discussing the war situation after eating their lunches. "Yeah, chimeras," she said, shaking her head in mixed dismay and disgust. "Of all things…"

Shirou nodded, and then turned away angrily. "So that's what's been attacking people along the river." He hissed. "No, worse than that, they…"

Shirou trailed off, shaking his head and clenching his fists. Sakura stayed silent, and several moments later, Shirou took a deep breath before looking at her. "And?" she asked. "What do you plan to do about it?"

"That's the big question, isn't it?" Sakura said unhappily, beginning to pace. "The obvious answer is go in and root them out, right? But, can we actually do that?"

"What?"

"Think about it." Sakura said. "Fuyuki is big, one of the biggest cities in Japan. The undercity through which runs most of the city's waterworks and a large part of electrical and other functions, plus the routes to access and service those functions among others, is just as big, if not bigger and more complex."

"Put another way," Shirou said. "It's like a maze."

"It is." Sakura said with a nod. "It'd be a nightmare navigating down there, all the while engaged in literal tunnel fighting. Worse, given how complex and big the place is, it'd be almost impossible to be sure we managed to clean them out for good."

"I see what you mean," Shirou said, lowering his face slightly. "I mean, I don't know much about chimera apart from, well, the basics, but that's enough. Even if a single egg or nest could be enough for the…hive, or whatever you call it, to grow back, just a single one of those monsters being left behind after we cleaned the place out would be bad enough. There's no point in starting something if we can't finish it."

Sakura nodded. "And also," she said. "If we get in too deep, we might get surrounded underground. Not really the best outcome, is it?"

"No, it isn't." Shirou agreed before pacing a few times and then kicking at a pebble in frustration. "But even so, we can't just do nothing!"

"I agree." Sakura said, also pacing again. "But if we can't go after those monsters directly, then we're going to have find some other way to deal with them."

Shirou stared at Sakura for a moment. "I'm guessing you already have some idea on how to that." He finally said.

Sakura looked at Shirou and nodded. "I do." She said. "Chimeras are Phantasmal Beasts of the Monstrous Rank, and are difficult to control, and impossible to tame. Considering we're probably faced with a full-scale hive, that means the magus behind them is quite confident in their ability to control so many chimeras at the same time."

Sakura paused, and began to pace again. "Basically," she said. "We find the magus in question, and then use their control over the chimeras to either destroy them where they are one way or another, or gather them in a single spot so we can destroy them all in one go."

"So, just like any other Master, is it?"

Sakura nodded. "Pretty much," she said before sighing. "Though, this assumes that the magus behind them does have sufficient control over the chimeras."

"What?"

"The ability to breed chimeras is a very…complex, mystery." Sakura said. "It's not simply a matter of just breeding together an animal and a Phantasmal Beast. Finding one of the latter aside, well, there's also the question of making the breeding successful in the first place."

Sakura paused and sighed. "The assumption is that if your mysteries are sufficiently complete and profound that you can breed chimeras, they would also be enough to control them." She said. "But that's not necessarily the case, is it?"

"No, now that you mention it, it isn't." Shirou admitted.

"Common sense dictates you don't breed as many chimeras as we're facing if you know you can't control them all up to a point." Sakura continued. "But, common sense isn't exactly common despite what it sounds like, and…"

"And?"

"Magi are the type to go big or go home when it comes to big risks and big rewards, aren't we?"

"Not all of us," Shirou said after a moment. "But, yeah, enough are, and if we're dealing with one of those…"

Shirou trailed off, but both he and Sakura wore grim expressions on their faces at the idea they were dealing with a greedy magus who'd seeded and grown a hive of chimeras to assist in their goal…and might not have complete control over them. "If that happens," Shirou finally asked. "Then what?"

"If the chimeras go out of control, you mean?" Sakura asked, and Shirou nodded. "If that's the case, then Kirei will suspend the contest, and order all Masters and Servants to focus their efforts on dealing with the chimeras and that irresponsible bastard who brought them along without a leash to hold them with."

"Can he actually do that?" Shirou asked in surprise.

"He can." Sakura confirmed with a nod. "For one thing, if the chimeras go out of control, then the conduct of the contest is clearly no longer being upheld. They'd probably be rampaging, after all. Worse, they'd probably be exposed to the public, either at once, or in short order."

"No way…but if that happens…!"

"That's right." Sakura agreed with a dark smile. "If the masquerade gets put at risk, then we're in deep shit. Thankfully, since it's a…side-effect, of the Holy Grail War, it's not really my fault but the Overseer's since it's his job to regulate the Holy Grail War, but still…I'd rather that not happen under my watch."

"…wait, why would it be on your watch? It's not like you're…are you…?"

"Oh, didn't I tell you?" Sakura asked in surprise before laughing. "Yeah, sorry about that. Yes, I'm actually the Supervisor of this territory for the Mages Association."

"Seriously?" Shirou asked before laughing and scratching the back of his head. "I guess that means I'm kind of…trespassing, aren't I?"

"Hmm…" Sakura hummed before shrugging. "Maybe…but I think I can let it go."

The two shared a laugh at that, and then Shirou returned to more serious matters. "Going back to Kotomine…" he said.

"Oh right, anyway, as I said, it's his duty as the Overseer to regulate the Holy Grail War, including making sure the masquerade isn't put at risk because of it." Sakura said after a cough. "So if those chimeras go on rampage, Kotomine will do as I said earlier, probably putting up an additional command spell or two as a reward – and incentive – for whoever takes the magus in question's head."

"He can give away command spells too?"

"Yes, the Overseer has their own set of command spells." Sakura confirmed. "It's to allow them to take control of any Servant if they need to bring them or their Master to heel. And just like how command spells can be surrendered, they can also be transferred."

"I see."

"Well, there is precedent for it." Sakura continued. "I'm not too sure of the details, but during the last war the Caster went on rampage, and the Overseer at the time did as Kirei could if the worst happens here and now."

"Well, let's hope it doesn't come to that then." Shirou said grimly. "Somehow, I just know that all seven Masters and Servants working together is going to cause a lot of damage, not to mention what a rampaging hive of chimeras can do."

"There's that too." Sakura nodded in agreement. "It might be best if we can find and deal with them before it comes to that. Either that, or Lancer's Master does."

"They're after the ones behind the chimeras too?"

"I think they are." Sakura said. "From how Kirei said it went, I think I – we – can take it as circumstantial evidence that Lancer and his Master are after them, one way or another."

"Enemy of my enemy, is it?"

"That," Sakura said. "Or they're after the research of the one behind the chimera. Well, that last is typical of magi so…"

Sakura trailed off and shrugged. "So what do you think we should do?" Shirou asked.

"What do you think?"

Shirou frowned at Sakura turning the question back at him, the younger girl just shrugging with a smile. "Well, I think," Shirou began with a sigh. "We ought to do things one at a time."

"Oh?"

"We're already committed to Caster so…" Shirou fumbled. "Let's find them first and deal with them, and then we can start looking for the chimeras' master. I mean, at least we already have a way to find Caster, and one with a good chance of working. That's not the case with the chimeras' master."

"Hmm…well, that's true," Sakura said worriedly. "And we'll need to think up of a plan to go up against a superior – if not as good as Caster undoubtedly is – magus."

"Wait, what? No, I understand Caster, but the chimeras'…"

"As I said," Sakura said. "Breeding and controlling chimeras are very…profound, mysteries. I don't even know how to begin with that, or at least none of my family's lore covers that."

Sakura shrugged. "No big loss." She said.

"Agreed," Shirou said before sighing. The two magi stayed silent for a few moments, and then Shirou gave Sakura a smile. "Well, I guess we just have to do the best we can, don't we?"

Sakura looked at him dryly for a moment, and then sighing gave a small smile. "Yeah," she said. "We can do that much at least."

"Leysritt, do you have what I asked you to bring?"

"Yes, my lady."

"Where is it then?"

"In the dungeons, my lady."

The little girl scampered off, Leysritt falling into step beside her sister as they followed after their mistress. "Did you encounter any difficulties while retrieving what Lady Illyasviel asked for?" Sella asked.

"Not as such," Leysritt replied. "But to an extent yes."

"That is rather inconceivable." Sella remarked.

"The quarries were fragile." Leysritt replied. "The difficulty came with securing one alive and as intact as possible, as per Lady Illyasviel's command."

"I see." Sella said, but said nothing more. Instead, the two homunculi silently followed their mistress down to the dungeons beneath the miniature castle built in Fuyuki's outskirts, to where Leysritt had deposited her mistress' desired specimen.

The chimera was…generally humanoid, in appearance, though with hardened scales covering its back and going around its torso and down its thighs. The chimera's legs ended with reptilian feet, and its arms likewise ended with reptilian claws.

A reptilian tail also sprouted from the chimera's back, tapering down to a spiked end. Its head was…strange, at once ape-like and pig-like in appearance, with small, beady, golden eyes and a fanged maw. Many of the teeth was broken, and indeed, the face showed signs of being bashed in by blunt force.

"Oh!" Illyasviel childishly said while running in circles around the chimera, playfully leaning in every so often. "So this is what a chimera made by Makiri looks like! Not bad, not bad…"

Sella and Leysritt stood along a nearby wall, next to a flickering torch. The former had her hands held relaxed in front of her waist, while the latter had one hand by her side and the other holding a large halberd at the ready beside her.

The chimera might be in chains after all, and she'd thoroughly beaten it down, but Leysritt had also seen it's – and its fellow chimeras' – regeneration ability in action. As such, she thought it best to be prudent.

"I'm surprised though," Illyasviel said, finally coming to a halt in front of the chimera, and cheerfully smiling at it. "I never expected a family as rotten through as Makiri is to be actually capable of making something like you. Well, maybe about century or even half a century ago they could have done it, but now?"

Illyasviel scoffed, leaning back as she did so. "That walking disease doesn't have what it takes." She sneered, all childishness gone. "Not anymore. So how?"

Chains tinkled as the chimera struggled against its bindings, but Illyasviel didn't even flinch, though Leysritt took a cautious step forward. A glance from Illyasviel had the homunculus returning to her place by the wall, and then Illyasviel turned back to the chimera.

"There are so many questions I want to ask, just from looking at you." She said. "How were you made? How do you work? What were you made from?"

Illyasviel closed her eyes, and took a step back. She paced a few times, and then coming to a halt turned smiling at the chimera. "Well, I have the time to find the answers out from you." She said. "And if you can't answer them, I'll just have to get some more of you, right? Makiri made a lot of you after all, though I have to wonder if you're all trash like the rest of that walking disease's legacy is or…"

Illyasviel trailed off, and narrowed her eyes. "Or," she continued after a moment, sounding less like the child she appeared and more like the eighteen-year old that she really was. "Did Makiri actually make an exception to the rule?"

Chains tinkled and groaned as the chimera struggled against its bonds once more, and Illyasviel raised a hand in response. A glowing halo flickered to life around the hand, and then with flicks of her fingers accompanied by the cracking of displaced air, sent concussive bolts of energy flying.

They slammed into the chimera's chest, bone audibly breaking from the impact and flesh crumpling inward and darkening from internal injuries. The chimera shuddered and strained, muffled noises coming from its mouth, chained shut by a chain wound below its jaw and around its head.

Illyasviel flicked her fingers again and again, the chimera refusing to subside and continuing to struggle even as its chest and torso were reduced to a blackened and bloated mass of bruised flesh and broken bone. The little homunculus was growing increasingly frustrated at the chimera's refusal to simply heel, Illyasviel actually growling at one point and finally letting out a frustrated yell several moments later.

The dungeon briefly went bright as day, and an echoing boom echoed through the mansion which actually shook for a couple of moments. As the light faded and the shaking subsided, chains hung limply from the ceiling, while others lay on the blood-splattered floor. The chimera's head, arms, legs, and parts of the chimera either hung from the chains or lay splayed out on the floor, but most of the body had been outright vaporized by a ravening blast of pure energy.

"Oh damn it!" Illyasviel shouted, kicking at the floor angrily. "Worthless Makiri trash! Why wouldn't it just heel? Damn it! Leysritt!"

"Yes, my lady?" Leysritt said, stepping forward with a bow.

"Get me another one!"

"As you wish, my lady."

Muttering to herself about ill-bred dogs and uppity worms, Illyasviel stomped off. Sella made to follow, only to pause next to Leysritt. "You may wish to capture more than one specimen this time." She advised. "Knowing our lady and with this episode as an example, one specimen will not be enough for her."

"Understood."

Sella nodded and followed after Illyasviel, Leysritt initially keeping step with her sister before they parted ways, the former needing to obtain additional specimens for their mistress.

Souichirou Kuzuki was not an easy man to surprise.

Despite appearances, it wasn't so much that he couldn't feel surprise, as much as it was that he didn't let it show or affect him. Even when the unexpected happened, whether it was a deviation in a plan or something that just happened, he didn't waste any time on worry or academic considerations. Instead, he used time otherwise wasted to consider the new situation variables, develop countermeasures, and put them into effect.

And through a combination of brutal physical and mental training, along with long years of experience, he could do all that in mere seconds.

But even for all that, finding his usually self-assured and unflappable Servant unhappily exorcising her frustrations with alcohol was something…difficult, to take in.

And that was quite surprising in its own way, not that he let either show.

"What has happened?" Kuzuki asked.

"I have finished a number of examinations on that captured chimera." Caster said, rising to her feet and bowing. "Welcome home, Souichirou-sama."

Kuzuki nodded. "What have you found that has disturbed you so, Caster?" he asked.

"To start with," Caster said, disgust dripping from every word. "What that chimera was bred from."

Kuzuki didn't say anything, instead silently urging Caster to continue. "The chimeras are born from Humans and blood worms." Caster finally said, visibly straining to keep herself from spitting.

"Blood worms?"

"The lowest kind of Phantasmal Beast, even more primitive than most familiars." Caster explained. "They are literally worms, which feed on flesh and blood, though they can subsist on prana if need be. By themselves they are useless, but their greatest strength ironically enough is their simplicity. They can be modified easily, and developed into more advanced forms with greater freedom than other, more complex life forms."

"I see." Kuzuki said, inwardly disturbed at the idea of worms and Humans being cross-bred but not letting it show. "How is it possible that worms and Humans can be bred together?"

"I am as of yet uncertain of that." Caster said. "However, my examinations have led me to believe that cross-breeding is a very…artificial, affair. It is not done by…natural, means, and requires external intervention at every stage."

Again, Kuzuki silently prompted Caster to continue, and the woman snorted and looked away in disgust. "While I will of course continue to work to infer the process," she said. "Even from just what I've uncovered so far…it's disgusting. Why in Mother Gaea's name would anyone want to breed Humans with blood worms of all things? Are they that desperate to breed chimeras, that they chose the simplest and easiest to obtain and use example of a Phantasmal Beast? And for that matter, why Humans as the paired animal species?"

"It could be that." Kuzuki said. Magus or no, he understood supply and demand well enough, and how universal the concept was. Between what Caster had told him about the blood worms just now, and the fact that the chimeras seemed to be…cannon fodder, for Rider and her Master…

…well, the simplest and easiest Phantasmal Beast to breed chimeras en masse with made sense in terms of efficiency compared to less…disturbing, but rarer and more difficult, Phantasmal Beasts.

Caster silently took this in, and after a few moments nodded slowly. "I…concede, the point." She said grudgingly. "The simplicity and versatility of the blood worms makes for an…uncomfortable, if undeniable merit. But why Humans though?"

"I do not know." Kuzuki said. "Perhaps you will find the answer with further examinations?"

Caster nodded slowly again. "True." she softly agreed.

Kuzuki nodded back. "Have you found anything else?" he asked.

"Yes," Caster said before taking a deep breath to recover her composure. "Apart from the chimera's own innate mystery – seeing as it cannot normally exist – there are a number of mysteries woven through its being. They are…surprisingly profound, leading me to believe that the system used by Rider's Master is at the very least, about five centuries old, to have this level of accumulated weight. Indeed, I daresay the chimeras are…incomplete, crystallizations, of her family's magecraft."

"You sound respectful."

"I am." Caster admitted with a hint of reluctance. "It's a clumsy and awkward system, with a particularly repulsive application, but I can…respect, on academic terms, a system of mysteries that's been built up to this degree."

"Professional respect, in other words."

"As you say, Souchirou-sama."

"And?" Kuzuki continued. "What are those mysteries 'woven through' the chimera?"

"I am still deciphering most, but I've identified one for high-speed regeneration, provided enough prana is available, and depending on the degree of damage to be recovered from. Bones, skin, scale and muscle are the easiest to replace, while organs and large quantities of…blood, and I use the term loosely, are more difficult to replace apparently. And of course, it's a given that the brain is irreplaceable."

"I am to take it then that unless instant death or critical damage is inflicted, the chimeras can quickly recover from their injuries on the battlefield?"

"You may."

Kuzuki silently considered this, and after a moment, nodded at Caster. "Fortunately," Caster continued. "That should not be a problem…for now."

"For now?"

"One mystery I have deciphered is an adaptation one." Caster said. "The chimeras 'learn' on a conceptual level, passively attempting to develop and improve resistances and even immunities to magical attack, or to physical ones. The former by adapting their mysteries and concepts accordingly, and the latter by growing improved physical defenses."

After another moment of silent prompting, Caster continued. "Now," she said. "While I strongly doubt they could develop resistances or immunities to High Thaumaturgy barring highly-improbable circumstances, the same cannot be said for simpler mysteries or repetitive forms of physical attack. Most likely, this is a result of their…ancestry: their bodies can quickly be adapted as needed."

"Then it wouldn't be a real issue for you," Kuzuki said. "But it may prove troublesome for my ability to fight on the battlefield."

"Not necessarily," Caster said with a smile. "If need be, I can provide you with passive-effect mystic codes to counter their resistances and defenses. But, even that may not be necessary."

"And why not?"

"Because the adaptations are individual." Caster said. "They are not shared by the chimeras among themselves, at least not naturally. Well, they can cannibalistically consume one of their own to add their prey's attributes to their own but…"

"But?"

"Given their purpose as cannon fodder, the chimeras' numbers being sacrificed to concentrate their quality does not seem a real concern."

Kuzuki considered this for a moment. "Yes," he agreed. "That much is true. Have you uncovered anything more?"

"I have made a few hypotheses on the remaining mysteries yet to be deciphered, but I would say until I prove or disprove them, there is little point in discussing them."

"Indeed," Kuzuki agreed. "Very well, continue as you have so far, though take care not let yourself get too aggravated by your findings. If necessary, put your examinations on hold to clear your mind, the better to conduct your examinations with."

"Yes, I understand Souichirou-sama. And thank you for your concern."

A/N

Mostly exposition from Caster, but also an appearance by our favorite psychopathic loli.

Next chapter, and we go back to the business of the war.