Kingdom of Flowers

(Continuing from the chapter: Knowledge)

(Sunday, approx 3pm. Emiya estate, Shirou's room)

(Sakura)

Rin and Sakura dueled with sideways glares for a moment, until Sasaku got up and deliberately walked in between them. "Hold that thought," Sasaku said, "At least until ah there you are." She waved over Shirou who had returned after she called him back over their mental link.

After a moment, he closed the door behind him and sat down on the bed next to Sakura. "Is this that important?" he asked with some irritation. Sasaku just shrugged and pulled a chair out of her Armory, except that it was a rather ornate one that looked to be made of marble and obsidian with silver inlays.

"Look," she said directly, "I forget sometimes you don't have the benefits of network intelligence, what with these handy telepathic links."

"Er, what's this about?" he responded with confusion dominating.

"You did hear about the Servants' discussion from Sakura?"

"I told him when he woke up," Sakura answered. "Since Rider and I share a link, I had all the details by then."

"Mhm. Well I knew you were up first since Rider mentioned it to me. Well I do understand if you suspected I was trying to keep it from you, but that would be a fairly ludicrous proposition from my position."

Sakura shared a confused look with Shirou. I have no idea why she got so serious suddenly, though she simply asked the obvious question; "But what is network intelligence?"

"A trick to allow multiple individuals to co-mingle cognitive processes. For example, someone might be able to simply 'remember' a relevant fact that separately I, but not they, might know." She grinned, "Since it works on a resonance-type mechanism, some husbands and wives have found other uses for it. But I digress. Saber seems to think I'm being tightfisted with teaching you. And while I wonder how he come to that conclusion..." she glanced sideways at Shirou,"I must admit that he and Kuro are burning through an impressive amount of magical energy trying to swap techniques, so I probably come off as slacking in comparison."

"So that's why-!" Rin muttered angrily. "Although I wanted to be there to watch..." Sakura blinked in surprise at this bit of information.

"Well, anyway I changed my mind, Tohsaka can stay."

"Really?" her enthusiasm was immediately stomped upon though. "Unfortunately, you probably won't be able to use it. You can try though." Based on Rin's expression, it seemed she took it as a personal challenge. I guess that's to be expected.

"I'll start with the following three necessities, I guess you could call them the trifecta, triumvirate, trinity, ah let's go with triangle." Sasaku held up three fingers and ticked them off, "Authority, Understanding and Magical Energy."

Caster gently curved her fingers around a worked silver cup that appeared. "Anyone want a drink? Seems I have varieties that exist in this age, but hmm, none from home. Typical." She took a sip. "I don't even really like wine." After tapping the cup on her armrest she took another sip.

"We're underage you know," Shriou said, but Sasaku just shrugged and replied, "I know that, I was asking if you wanted any. We don't have your drinking age back home."

"How is this relevant?" Sakura questioned, realizing it's clearly not a random diversion. "The laws there don't apply here."

"But they do for some definition of here," was the reply. "((Realm Creation)) and ((Authority)) are inseparably linked. If there is no Realm, the Authority applies to nothing. Without Authority, what defines the Realm?"

Sakura and Rin looked at one another as the same thought came to them, namely but a Servant's Skills are particular not to them, but also the class vessel they are in.

"Long story short, ((Realm Creation)) is the equivalent of changing something so that it has the state of 'being in my home civilization,' if only partially. It has a cost to maintain because obviously the World prefers not to have bits of itself being annexed away, as it were. Thus, my Authority works inside it."

"But you never said what your Authority covers?" Rin asked.

"Everything that I would have had permission to do, subject to (magical) energy costs, obviously. The main conceptual limit though, which is what you're asking, is 'things that do not go against the tenets of my civilization' as well 'being inside'. I will point out that your magecrafts, as they do not exist at home, are therefore by default not forbidden."

"You were shooting spears outside," Shirou pointed out.

"Indeed, and while some forms of Thaumaturgy are territorially limited, you mustn't think overly much about the area concept." Sasaku nodded. "The Bounded Field we are in is one mechanism of actualizing of the Realm, by pulling space into it. I myself, as a member of the civilization, must be inside it, as a result the Realm must at least also exist within the space of my body. And since the boundaries of the Bounded Field are a bit fuzzy, I can affect some of the space physically surrounding me. Think of it as a nation's territorial sovereignty, as well as people holding citizenship."

"That's why you had to touch Rider's Field foci to break them!" Rin exclaimed, having wondered about that for some time. "Pretty much, those are concentrated points which assert to the World 'such-and-such space is inside the Bloodfort Andromeda' and after taking control of that space, I simply said 'it does not'." Sasaku clarified. "But for throwing spears, I only need to get the thing moving. It's a fairly normal physical object past that point. Now, the World crushes them out of existence afterwards, due to being tagged as 'items inside the Armory' while being outside, so I can't reuse them."

"But a thaumaturgy is weak if there's very few people who believe in it," Rin added thoughtfully. "You still have an attack that harms Servants."

"Yep," Sasaku cheerfully agreed. "Unless some significant fraction of humanity decides to believe in this, you're restricted to Realm-Authority mechanics. But as it is possible to deputize, I can hand down a certain amount of it. If you absorb a portion of my magical circuits, it also should function similarly to having someone's password to access their computer."

"I'll skip the second part for the moment. Magecraft runs off magical energy, which sometimes here in the east they call Prana, but anyway think of it as another type of energy." Shirou nodded, perhaps due to having heard his Servant's updates on the amount of energy being stored.

"In a way, we think of the energy stored in our bodies as different from the chemical energy in gasoline. You eat food, you generate magical energy, that sort of thing." Sakura and Shirou assented to this easily, though by her frown Rin disagreed somewhat.

"Anyway, there's basically two types, sources of this, the planet itself generates mana. While in the Age of the Gods it suffused even the air, in modern times gathering a good amount is mostly restricted to leylines. Isn't that right Tohsaka?" Sasaku abruptly tossed a question in her direction.

"Yes," Rin nodded. "Fuyuki is important as one can access several leylines in this area. Only, due to being in the East, it was largely overlooked except by Zelretch and those involved in the Holy Grail project. Fuyuki's leylines are in many ways the Tohsaka's biggest contribution to the Grail system."

Sasaku nodded her thanks and took up her explanation. "The other major source comes from yourself, od via magical circuits. Mana continues to decrease in availability, which brings up a natural question." She paused to smile at Rin before posing her next question. "Where do magic circuits come from?"

"Magic circuits are part of a magus' soul, and also have a physical manifestation like the nervous system, but for channeling magical energy." Rin answered quickly. "But it's not possible to change what you have from birth."

"Except via magic crests," Sakura added with a frown, thinking about their earlier discussion on the topic.

"Don't be distracted by that," Sasaku murmured. "But where do the circuits 'you have from birth' come from?"

"Well, it's a matter of descent," Rin said, slightly uncertain what exactly she was being asked. "Older lineages tend to be more powerful, which is to say more and/or better quality circuits."

"That's not it," Caster returned with an amused tone. "Put another way, where did you personally come from?"

"My parents had me?"... "If your parents had a second child, where would she come from?"

"What is the point of this?" Sakura snapped abruptly, surprising everyone present except, perhaps, Rin. "Magi have children like everyone else."

"No, wait, I think that's her point," Shirou spoke up while trying to sooth her, and keeping the topic in mind. "If I had to guess, you're thinking; if Tohsaka's parents had a second child, then 'the Tohsaka family' would have more circuits in total. Accounting, but with magical energy, though you're thinking on the scale of 'a civilization' rather than just 'a family'."

"But a magic crest can only be passed down to one descendant," Rin interrupted Sasaku, who was about to respond.

"Perhaps, of the two things those transfer, spells don't count as each individual needs Understanding, even if they can avoid the Authority constraint. And the second child could still make a new crest and pass it down to keep the circuit alive. So the next generation of say four children now has combined the circuits of four of them and the ones passed down from the previous two of you."

"My god," Shirou realized. "What you mean is that if you go on, you would have eight, with the inheritance of the first six. And then sixteen with inherited circuits from fourteen."

"Ha ha ha," his Servant laughed, though it oddly seemed dangerous rather than merry. "You had an advantage in figuring that out though, didn't you? Admittedly, I do intend to research immortality if not some version of Uplifting, but I make no guarantees."

"How can that- you're talking about multiple generations worth for that?" Rin appeared to be losing her cool.

"Too small," Sasaku agreed. "It would only be a side-benefit of constructing a whole civilization. Well there's many possible paths and a lot of research to do."

(After some discussion about Understanding, which is exactly what it sounds like on the tin)

"If our Mysteries don't exist in your homeland, how can you use them here?" Rin asked. "You literally performed a Heroic Spirit summoning. Where did you obtain the Understanding you need for that?"

"That's the thing, isn't it?" Sasaku grinned mischievously. "It's possible to learn. By the way, your gem magecraft is interesting, though we do have methods for storing energy, which over here works for magical energy."

Sasaku pulled out something the size of a thick coin. It looked like a single red petal suspended in a clear disc. As she held it out to Rin, the item began to slow slightly. "Two pieces of homework for you, with a reward. First, figure out how to drain my magical energy from this 'crystal capacitor' and fill it with your own. Second, figure out how to make one."

"What's the reward?" Rin asked after Sasaku made it clear she had finished speaking.

"You'll be able to make as many as you want, and not rely on hunting for gems?" Sasaku seemed to find this amusing for some reason. "I suppose it should be mentioned that if you can create one, it will probably have very high compatibility with you as well."

"But as for summoning Saber, the man who summoned me had done his homework. A+, it satisfied my Understanding very satisfactorily." She handed it to Sakura, who flipped it open and noted immediately a familiar magic circle drawn within.

"By the way, you never told us about your first Master," Shirou pointed out.

"That bastard? I killed him."

l

Notes:
Magical energy/mana/od explanation ahoy.

If you're wondering about what tipped Shirou off, the reference is to when Sasaku asked him if he would like to be the father of an entire civilization. That and the fact her skill is named ((Realm Creation)) rather than the standard ((Territory Creation)).

Don't take Sasaku's plan too seriously. As she herself said, it was only one possibility (actually that's the reason she didn't want to go into details) as she needs more information to even guess if it is doable. If you noticed it was less of 'teaching' and more of a 'discussion in disguise', you're right. Sasaku tends towards the dialogue genre.

Sasaku has all kinds of mundane stuff in her Armory. Basically think of pack-ratting it up over a thousand years and actually being able to access it. But she doesn't have stuff like Mystic Codes let alone Noble Phantasms, as they don't exist in her home civilization. For that matter, the World also removed from her collection things like strategic or future weaponry.