Carrying Jin and the others, the Aristotle arrived in the Nord Federation in about two hours.
It touched down at the All-Creation Clan's airfield.
Since its descent had been visible from afar, a large crowd had gathered by the time it landed.
Naturally, the real Sion was aware of their arrival, so Sion D—her Doppel—went into dormancy inside the Aristotle.
"Welcome, Jin. Welcome, Maquina-dono. Welcome, Reiko-chan....And welcome, Lady Erna."
Sion was the first to offer a greeting.
"Maquina-dono, Jin-dono, welcome! Lady Reiko, welcome! And Lady Erna, is it? Welcome!"
Lordtoss gave his welcoming speech as well.
After receiving greetings from several others, Jin and his companions headed directly for Sion's home—the Clan Chief's residence.
By this point, the only Nord Federation locals remaining were Sion, Lordtoss, Vita, Ludmila, and the household servants.
"Now that the date is set, everyone is raring to go," Sion remarked.
"Yes, my craft is about eighty percent finished as well," Lordtoss added with a smile.
"I'm looking forward to seeing it. On my end, I'll put my efforts into getting the competition venue ready."
"U-Um, Jin-san, won't you be participating this time?" Vita asked.
"No, not this time. I want this to be purely an exchange between the Northern People and the Lauren Continentals."
"I see."
"So, given my position, I have to stay neutral. Otherwise, I'd be rooting for you, Lordtoss."
"Those words alone are more than enough," Lordtoss replied, smiling warmly.
"Oh, right. Once the Marikka Cup wraps up, how about we hold a private race somewhere?"
"Oh, that sounds wonderful! By all means!"
And with that, the matter was settled.
With plenty left to do, Jin stayed at Sion's residence only briefly before returning straight to Hourai Island.
"Welcome home, My Lord."
"Yeah, I'm back. I doubt anything has changed, but how are the preparations coming along?"
These preparations, of course, were for the redevelopment of Kutsudo Mine.
"Yes, everything is fully in order. We have fifty Smith units, fifty Land Squad units, two Daidara units, and two Mole machines standing by."
"That should be more than enough."
The giant Daidara golems were necessary for leveling the airfield, while the Moles would handle the ultra-deep excavation. The Land units would manage tunnel maintenance, and the Smiths would oversee ore refining.
"All right, let's get started right away."
"Understood."
After confirming there was no one within a ten-kilometer radius of Kutsudo Mine, Laojun dispatched the entire workforce via transporter.
Leaving the operation—including on-site monitoring—in Laojun's capable hands, Jin finally headed toward the House to relax.
"Welcome home."
Elsa greeted him at the door. Since he had been beside Erna until just moments ago, Jin felt a subtle twinge of oddity.
"Well, a lot happened, but it's all taken care of."
Elsa, having accompanied him as Erna, naturally knew every detail, but Jin couldn't help saying it aloud anyway.
"Mm. Good work."
"The Marikka Cup is less than a month away, too. It's going to be busy."
Knowing full well that Jin wouldn't be able to sit still for a single day despite his words, Elsa simply offered a gentle smile.
Meanwhile, at Kutsudo Mine to the west of Toka Village, the dead of night had settled in.
"First, let us level the airfield while no one is watching."
Taking heavy, measured strides forward, the two Daidara completed the bulk of the earthmoving with ease.
Fine adjustments were naturally beyond the reach of the fifteen-meter-tall Daidara, so that task fell to the Land squad.
After carrying out the heavy labor of clearing massive boulders and filling deep depressions, the two Daidara returned to Hourai Island via the large Warp Gate aboard Condor 3, which had arrived to retrieve them.
"I leave the rest to the Land squad."
With that, an area of roughly one square kilometer was cleared and prepped as an airfield—all within a single night.
Even as dawn broke, not a soul was in sight.
The Land squad worked in silence, putting the finishing touches on the grading before casting Harden across the ground.
This engineering magic was Jin's original creation, a spell that solidified the earth as though it had been paved. Its greatest merit was its reversibility.
In other words, returning the ground to its natural state was entirely effortless.
The Land squad pressed on with their work, ensuring the airfield's leveling would be fully complete before the day was out.
"Moles, proceed with excavation toward the ore veins."
Simultaneously, the exploration—or rather, the actual mining—of the ore veins began.
Using Grand Search, rich deposits of gold and silver were discovered three hundred meters underground.
Elsewhere, veins of all-attribute magi-crystals were unearthed as well.
The two Moles burrowed toward the veins at a thirty-degree downward angle, advancing at a steady pace of one meter per minute.
Covering three hundred meters would take three hundred minutes—exactly five hours.
Because the rock pulverized along the way contained traces of iron, copper, zinc, and other metals, the Smiths refined the rubble as it was cleared.
Although the concentration was low, their power source was the ambient free ether in the air, allowing them to refine the materials continuously without worrying about efficiency.
As a result, over the course of five hours, approximately two hundred kilograms of iron, one hundred kilograms of copper, sixty kilograms of zinc, and ten kilograms of nickel were extracted.
The slag was temporarily piled up into mounds of waste rock known as spoil.
Crushed into fine gravel, it was ideal for macadam paving.
Plans were already in place to use this material to pave the roads around Toka Village in the near future.
"Hmm. Just as expected, there is an adamantite vein."
For its size, Planet Ars possessed a remarkably thick crust rich in subsurface resources. Whether those resources could actually be extracted, however, was another question entirely...
"Still, hydrogen sulfide... How troublesome."
As the excavation went deeper, pockets of hydrogen sulfide began venting out.
The outer plating of the Land and Smith units was crafted from 64 light silver—titanium—giving them high resistance to the gas.
Standard golems, however, relied heavily on iron-based components, which were highly susceptible to hydrogen sulfide corrosion.
"Leaving it in a state that cannot be utilized after our withdrawal would defeat the purpose."
Since the source lay even deeper underground, cutting it off at the root proved difficult.
"For now, our only choice is to seal the rock fissures."
Laojun opted to block the escape routes, eliminating the immediate hazard.
"We will need to implement a permanent solution eventually..."
Since hydrogen sulfide was slightly heavier than air, Laojun considered pooling it in underground reservoirs and neutralizing it at regular intervals.
Furthermore, an investigation was necessary to determine whether the gas was continuously generating or merely accumulated in pockets.
If it were simply trapped gas, resolving the issue would be far simpler.
Two days after the operation began, an inspector from the Klein Kingdom visited the mine alongside Jin's Doppel.
"Oho! Well, look at this..."
"How does it look to you?"
Before them stretched a one-square-kilometer airfield, a substantial mound of spoil, dedicated refining sheds, and clearly visible new mine shafts.
"Truly magnificent work, Jin-dono."
All of this was slated to be handed over to the Klein Kingdom in one month's time. The profits to be reaped from it would be anything but small.
After observing the operations for half a day, the inspector returned to the royal capital, thoroughly satisfied.