The next day, the 29th, Jin and Elsa warped to Hourai Island after breakfast.
The thought of what kind of master never showed his face at his own castle crossed Jin's mind for a moment, but those feelings vanished the moment he stepped into the laboratory.
"Now then, let's pick up where we left off yesterday. Elsa, is there anything you don't understand?"
"Mm. I mostly understood the method yesterday. Now, I want you to tell me what materials I should use."
Elsa seemed to be having trouble deciding on the materials for the mascot, likely because Hourai Island had everything imaginable at her disposal.
"You should try using the same structure as an automata," Jin suggested.
"Eh?"
Jin explained that she should place magic silk floss padding over a simple skeleton and then cover the exterior with magisilk.
"There's a type of doll called a 'stuffed animal.' It's similar to that, but by including a skeleton, you can make it strike all sorts of poses."
The concept was essentially a one-third scale doll.
"That sounds interesting. Being able to pose it is quite novel."
Apparently, the dolls in this world had not advanced to that level of articulation yet. Jin provided some light silver for the skeleton and settled in to watch Elsa work for a while.
"You should consider the head-to-body ratio."
"The ratio... Ah, I understand."
Knowledge gained through Trans Info wasn't something one could master overnight; Jin knew this from experience. At first, it felt like having a book inside your head, where flipping through the pages took time. However, once a piece of knowledge was used, it would flow smoothly from then on.
Elsa was the same; she would only realize things after Jin pointed them out, time and again. As an experienced mentor, Jin led her skillfully, drawing out the knowledge she had acquired.
"I think a ratio of four or five heads tall would be best."
Elsa seemed to have finalized her design.
"I want the joints to be at the neck, shoulders, elbows, wrists, waist, hips, knees, and ankles."
"Yeah, that sounds good."
"U-Um... I think I should make them... ball joints?"
Jin nodded. In truth, this was something of a practice run for eventually creating golems and automata.
"Assuming a full height of about 130 centimeters, since it's one-third scale... I'll make it 45 centimeters."
It was a reasonable size for a doll intended for display. Jin nodded and let her proceed.
"The skeleton... about this much. 'Forming'."
"Oh, you've gotten good at that."
Elsa shaped the basic frame of the mascot's skeleton in one go. While it didn't have joints yet, the fact that the head and four limbs were properly proportioned showed her rapid improvement.
"Really? I'm happy."
Elsa smiled and continued her work.
"'Forming'. 'Forming'. 'Forming'."
The joints took shape, and the fingers and toes were refined. Jin watched on, nodding silently.
"Now I'll attach the padding....I want to do that part by hand."
There was no need to do everything with magic. Jin approved of her choice.
Under Jin's watchful eye, Elsa completed the basic form of the doll in just about thirty minutes. Even for a one-third scale model, her speed was remarkable. It was only possible because she had a clear, vivid image of what she wanted to create.
"Now all that's left are the eyes, hair, and clothes."
Since those were a matter of personal taste, Jin wasn't needed.
"Well then, I'm going to go handle some of my own work. Call me if you need anything."
Jin left Elsa to her task and took Reiko up to the second-floor laboratory.
"Reiko, how is it?"
Jin immediately asked about the condition of the tactile sensation device he had installed in her.
"Yes. As you said, it has not affected my movements. And while I can certainly feel 'touch,' it is... how should I put it? The reaction feels dull, or perhaps delayed."
"I see..."
A delay in perception was fatal during high-speed operations. Jin considered the cause. One possibility was the magi-sequence he had constructed; there was certainly room to make it more efficient.
"And then... I suppose it's the clock-up, after all."
Since the reaction of the magical skin was instantaneous, Jin concluded that the perception lag was caused by the time required to read and recognize the signals.
"Hmm, even if I optimize it, I'll likely only be able to double the speed for now," Jin muttered as he reviewed the magi-sequence. For an operational speed similar to a human's—like Ar's—there would be no problem at all. However, Reiko was capable of moving at nearly a hundred times the speed of a human when necessary.
"Isn't there some effective way to speed it up...?"
Jin crossed his arms, lost in thought. After considering every angle, he reached a conclusion.
"Let's take it one step at a time."
In other words, rather than trying to solve everything with a single fix, he would adopt the spirit of "even dust, if piled up, becomes a mountain." He would speed up each individual part of the system, aiming for a significant overall increase in performance.
"First, the mana transmission speed."
He hadn't given it much thought before, but Jin wondered exactly how fast mana traveled through a magi-crystal. He recalled that in an electronic circuit, the speed of electricity—or the speed of electromagnetic waves—was roughly the speed of light.
Sound waves changed speed depending on the medium. Light did the same. So, what about mana?
The answer was that its speed changed depending on the medium. This was supported by the fact that mana was known to be slightly deflected by magi-crystals of the same type. It was the same principle as a prism. Light slows down in substances with higher density (more accurately, a higher refractive index). Mana appeared to follow the same rule.
"Which means it likely varies depending on the magi-crystal..."
Thinking along those lines, Jin remembered Saki's face. He wondered how she would approach such a problem.
"I might have to bring her to Hourai Island eventually," he mused aloud.
Reiko reacted to the words that had slipped from his mouth.
"Father, are you speaking of Saki-san?"
"A-Ah. You were listening?"
"Yes....Saki-san occasionally has a way of thinking that is a little similar to Mother's. She might be a great asset to your research, Father."
Reiko's observation was unexpected.
"Is that so?...Well, Elsa wanted to see her too, so maybe I'll bring her here soon. Though it would be to Kunlun Island first, of course."
"Yes, that would be for the best."
Putting the thought of Saki aside for the moment, Jin returned to brainstorming ways to improve processing speed.
"Speaking of magi-crystals, I wonder how Elradrite would perform?"
It was still a mineral shrouded in mystery. Its effect was said to be the amplification of magic and mana, but that wasn't entirely accurate. One could not create something from nothing.
"It's more accurate to say it amplifies the incoming mana using the mana nearby."
By using ambient mana—the most accessible being the mana of the caster—it could turn a spell with a power of one into ten or twenty. That was the property of Elradrite. It didn't allow a magi to use magic beyond their actual capacity; it strictly amplified the resulting effect.
"That's it!"
A sudden flash of inspiration hit Jin.
"If I use Elradrite's amplification effect to boost the mana signals generated by the tactile sensors, wouldn't they become easier to perceive?"
Jin immediately set to work. He removed the tactile sensation device from Reiko and incorporated Elradrite into the pre-perception stage. He made no other modifications so that he could accurately judge the effect of this single change.
"Now then, Reiko, how about this time?"
Reiko rebooted and tested the system by grasping and lifting the tools and magi-crystals nearby.
"Father, this is incredible. It is much clearer than before."
She reported a significant improvement. It seemed that amplifying the signals had resolved the issue of perception taking too long because the original signals were too faint.
"I see! Right now, it's amplified about ten times. Does that seem sufficient?"
"Yes. It feels as though with just one more refinement, there would be no discomfort even at full power. Shall we test it?"
Satisfied with Reiko's response, Jin shook his head.
"No, that's enough for now. I'll take it off one more time to refine the magi-sequence. If I do that..."
Looking at the system comprehensively, he believed he could make it fully compatible with Reiko's performance even at her maximum power. Jin felt his expectations swelling.