The following day, October 21.
Saki, Goose, and Vivienne began a deeper investigation and analysis into the relationship between Onogoro Island and the Progenitors.
Meanwhile, Jin, Elsa, Laojun, and Reiko focused on developing the tele-observation device.
"Hey, Jin-nii, about the illusion barrier..."
Elsa spoke up abruptly, as if she had been pondering the matter since the previous day.
"Is it correct to say it's a magi-engineering technique that makes something appear where there is actually nothing?"
"Yeah. What about it—! I see!"
Realizing what Elsa was getting at, Jin clapped his hands together.
"You understood from just that? You're incredible, Jin-nii."
"Kufu, they call that being on the same wavelength, don't they?"
Saki, who was supposed to be focusing on the Onogoro Island and Progenitor connection next to them, chimed in with a tease.
Elsa’s cheeks flushed slightly at the remark, but the comment had no effect on Jin, who had already entered his technician mode.
In essence, Jin suspected that the tele-observation device used by Helente and her group worked by using magi to construct something akin to a repeater in a remote location, which then allowed them to view far-off images.
Jin had hit a dead end while trying to approach that technology through various teleportation-based theories.
But now...
"Illusion magic involves projecting an illusion in a distant location using magi—specifically, using ether waves as carrier waves."
"Mm."
In terms of concept, it was somewhat similar to a laser hologram.
"If we write magic circles or magi-formulas instead of just those illusions..."
"Yeah, yeah, I can tell it sounds like something amazing," Saki said, impressed despite not fully grasping the mechanics.
"Alright, let's give it a try."
Saki, Goose, and Vivienne remained in the dining room to continue their discussions, while Jin and Elsa moved to the workshop.
Jin immediately began the experiment.
"The range can be very short for now. This is just a prototype, after all."
With Elsa assisting, the prototype was completed in about thirty minutes.
"This should be able to manifest a Light Ball at a location twenty meters away."
"Will it work even if there's a wall in the way?"
Jin nodded at Elsa's question.
"Of course. Ether waves aren't even obstructed by a planet. Let's try it."
Jin activated the prototype, aiming it outside the laboratory. Elsa ran to the workshop window and peered out.
"Jin-nii, it's a success. It's glowing."
"Good."
"As expected of you, Father," Reiko added.
"Now, I'm going to develop it further. There are two paths: extending the distance and making it compatible with complex magi-formulas and magic circles."
"Jin-nii, can I try working on the distance?"
Jin thought for a moment before nodding.
"Sure, I'll leave that to you. It'll probably come down to the convergence of the ether waves, so you might want to ask the Mini-Smiths for help."
"Mm, I understand. Thanks for the hint."
Meanwhile, Jin decided to test a spell that required a more complex magi-formula than a simple Light Ball.
"Hmm, 'Fire' isn't really that much more difficult..."
Jin pondered which spell would make it easy to verify success. Then, it hit him.
"...I'll go with 'Magic Eye'."
After all, that was the ultimate goal of this device.
Jin began programming the magi-crystal that would serve as the source for the illusion barrier.
"This is incredibly delicate work... It's fine for a prototype, but for the real thing, I should have a Mini-Smith... no, a Milli-Smith do it."
Milli-Smiths were specialists in ultra-fine processing. They were ultra-miniature Smiths only five millimeters tall.
On her end, Elsa was attempting various methods to extend the effective range.
She reached ten kilometers without much trouble, but things started getting unstable around the twenty-kilometer mark.
The Watcher was monitoring the Light Ball for her, and reported that the spell was manifesting inconsistently. Furthermore, the point of manifestation was wavering and unstable.
"Elsa-sama, for one thing, the magic tool generating the wave is likely not mounted securely enough," Laojun suggested.
Even a microscopic tremor at the source would result in a massive deviation twenty kilometers away.
Following this advice, Elsa prepared a solid foundation and mounted the magic tool to it. This almost entirely eliminated the wavering, but the manifestation was still intermittent.
"It must be the convergence after all..."
"How's it going, Elsa?"
Jin arrived just as Elsa was lost in thought.
"Are you finished on your end?"
"Yeah, I've reached a good stopping point, so I'm having the Milli-Smiths handle the processing now."
"Milli-Smiths..."
Elsa's eyes widened, realizing just how precise the work must be. She also realized that to bridge an immense distance, they needed to aim for zero error.
"I think I solved the stability of the location by fixing the magic tool in place. But the activation itself is..."
"Ah, so it is a convergence issue."
"Mm, yes."
"In that case..."
The part acting as the 'lens' to project the illusion was a section of the magi-crystal itself. Jin explained that it was vital to form its physical shape as accurately as possible.
"I agree. That makes sense."
"Then first, let's eliminate any defects in the crystal....'Stransform'."
"Incredible. I was going to ask the Mini-Smiths to handle the shape, but I didn't think to address the crystal structure itself."
"Well, I am a technician, after all."
Jin laughed, saying that while he had the habit and intuition for craftsmanship, he couldn't match Elsa's creative leaps.
"Thank you. Even if it's flattery, I'm happy."
"No, it's not flattery..."
As far as Jin was concerned, he felt truly supported by Elsa, who was capable of unique insights he might never have.
"A-Anyway, let's try this one."
Acting a bit bashful, Jin looked at the magic tool in front of Elsa.
"For the actual machine, we might want to use adamantite... or perhaps even hyper-adamantite."
"Eh?"
As if reading Elsa's "Are you really going that far?" expression, Jin continued.
"Yeah. A perfectly 'rigid body' is a technician's dream. I think that material would get us pretty close."
A microscopic distortion or deformation would result in an error that couldn't be ignored over hundreds or thousands of kilometers. Elsa thought she understood the logic, but having it pointed out by Jin made her realize the sheer scale of the precision required. It was like how a high-magnification telescope was impossible to use while held by hand.
"Mount it firmly, and keep the precision high."
With that, Prototype No. 2 was completed.
"I'll test it. Laojun, please confirm."
They started at twenty kilometers.
"It is OK. There is no blur."
"Then, thirty kilometers."
That was also a success. Eventually, they confirmed it functioned without issue up to one hundred kilometers.
Meanwhile, Jin received word from the Milli-Smiths that they had finished their processing.
"Alright, let's try it."
Jin woke up the magic tool.