The Capricorn 1 made its way up the Erme River. Whenever the riverbanks grew too narrow, it simply waded into the water.
Its six-meter-long legs didn't even sink halfway into the depths, allowing for steady progress.
Though they encountered several small waterfalls along the route, the vehicle’s fifty-degree climbing capability made "traversing high"—climbing the banks to bypass the falls—look effortless. By the end of the day, they had reached the glacier that served as the source of the Erme River.
Naturally, Jin had equipped the soles of the vehicle’s feet with retractable spikes to prevent it from slipping on the ice.
"We’ll be at the Klein Kingdom border soon," Jin muttered while consulting a topographical map.
"Did you make this yourself, Jin-sama? It is a wonderfully precise map!" All-Creation exclaimed, peering over his shoulder with a look of surprise.
"Yeah. We’re currently right here, at the edge of the glacier. We’ll be climbing up the ice for a while; there are fewer obstacles that way."
Since it was midsummer, there was little snow on the surrounding mountains, which Jin calculated would minimize the risk of avalanches.
A check with Sonar revealed the glacier was over twenty meters thick, more than enough to support the weight of the multi-ton Capricorn 1. If they hit a true dead end, the gravity control magi-device would allow them to scale rock faces steeper than seventy degrees or even hover for short periods. However, hovering was a massive drain on mana; even five minutes of flight would likely consume half of their emergency ethenol supply.
With Land 1 at the helm, the vehicle could travel twenty-four hours a day. The drop in temperature at night further reduced the avalanche risk, which was a welcome advantage. They had timed their progress specifically to ensure they crossed the most treacherous high-altitude zones under the cover of darkness.
Jin and the others finished a dinner of travel rations before reclining their seats to sleep. Aside from Land 1, who was busy piloting, Reiko and Anne remained awake, keeping a vigilant watch through the windows.
Furthermore, Falcon 2 and 3 were monitoring from five thousand meters above, ensuring they were ready for any unforeseen complications.
『This is Falcon 2. No obstacles detected on the path ahead. Continue as planned.』
『Capricorn 1, acknowledged. Maintain surveillance.』
"It's quiet, Reiko Onee-sama," Anne remarked.
"Yes. I hope it remains this peaceful."
The night passed without incident, and the Capricorn 1 successfully cleared the high-altitude mountain range—the journey's most difficult section.
Even at a modest speed of twenty kilometers per hour, the advantage of moving non-stop was immense. They had covered over three hundred kilometers in a single day.
The route Jin and Laojun had charted followed the Erme River to its headwaters, climbed the glacier, and crossed the mountain saddle. While it was a longer path geographically, the north side of the mountains was largely barren wasteland without trees, making it ideal terrain for the Capricorn 1. Conversely, trying to bypass the mountains to the south would have meant struggling through dense coniferous forests, which they predicted would have been a grueling, time-consuming task.
This efficiency was only possible thanks to their aerial reconnaissance—a perfect example of "the longest way around being the shortest way home." The only minor drawbacks were several small river crossings, though none proved to be an obstacle for the Capricorn 1.
The next morning broke cloudy. The atmospheric conditions on the north side of high mountains favored cloud formation, especially during the summer.
"It was cloudy every day when we came through here, too," Sion noted. "It only cleared up once we got over the mountains."
Jin suspected that moist air from the cold northern sea was flowing in as a sea breeze, hitting the mountains and condensing into clouds. He couldn't help but wonder if this constant cloud cover contributed to the cold weather damage plaguing the demon territory.
The group finished breakfast while the vehicle continued its steady march. They had just crossed another river. Being so far upstream, the water was less than ten meters wide and only about fifty centimeters deep.
"Things are going smoothly so far."
Jin opened the skylight to circulate some fresh air. The biting mountain air rushed into the cabin.
"Jin-sama, it is a bit cold," All-Creation whispered.
"Ah, sorry."
Jin, operating the Body Double, could monitor the ambient temperature, but he lacked the physical sensation of feeling "cold" or "hot."
Once he closed the skylight, the interior stabilized at around twenty degrees Celsius—a comfortable temperature for a single layer of long sleeves. While the demon race was generally resistant to the cold, the high-altitude air was apparently too much even for them.
"The outside temperature is five degrees Celsius."
Jin had crafted a mercury thermometer for the journey. It was a simple device—zero for the freezing point, one hundred for the boiling point, with the space between divided equally—but it was perfectly functional. However, since atmospheric pressure had not yet been formally defined in his system, it remained a simplified version, as boiling points fluctuated with altitude.
"Heh, you can actually measure it like that? How convenient," Sion said, looking at the thermometer with genuine interest.
"Don't you have these in the demon lands?"
"Not really. We have 'temperature indicators,' though."
According to Sion, these were discs or squares with a material derived from a magical beast attached to the surface; it turned red when it was hot and white when it was cold.
Like a liquid crystal thermometer, Jin mused.
The Capricorn 1 crossed a second river. According to the map, it was the last one. From there, the terrain leveled out. Land 1 adjusted their course away from the mountainside and headed due north, finally aiming for the Pazdext Great Isthmus.
Another half-day passed. The ground conditions improved further, allowing them to accelerate to thirty kilometers per hour. As the sun began to dip low in the long summer evening, the sea appeared as a thin line on the horizon.
"I see the sea!" Sion cried.
"Ah, truly! We’ve finally made it back..."
Though the coast was still over fifty kilometers away, the sight of familiar territory brought a look of profound relief to the sisters' faces.
But that relief was short-lived.
As they drew closer to the coast, the cloud base rose and visibility sharpened. Within that clear air, an eerie sight manifested.
"Si-Sister, is that... could it be...?"
"Yes... those are Rock Giants."
"The Toying Clan... why?"
"They were supposed to be neutral!"
"What is that?"
In the Hourai Island command room, Jin stared at the magi-screen as he operated his Body Double.
The objects looked like massive statues. From high above, they were camouflaged so perfectly that they were indistinguishable from the surrounding boulders.
"A massive golem...?"
It was a literal giant, just like something out of a video game. It appeared to be made of stone. And there were ten of them.
Suddenly, the giants began to move. Their target was unmistakably the Capricorn 1.
"They're fast for Stone Golems."
The Stone Golems used for mining on Hourai Island were between two and three meters tall. They were powerful but slow. In contrast, these ten-meter-tall giants displayed an agility that seemed to defy their massive size. Perhaps they were constructed from a lighter type of stone.
"Well, they’re still nothing compared to a Titan."
The Titans Jin had built could move at a human-like pace. This meant they were ten times faster than a human of their scale, with striking speeds to match. Given their immense weight, their physical impact was catastrophic.
The massive Stone Golems on the screen were moving at less than a fifth of a Titan’s speed.
"I suppose this is a good chance to test the Capricorn 1's defenses," Jin muttered to himself. He sent a command through the manacam to Reiko, Land 1, and Anne.
"Prepare for long-range combat."
(Father has issued his orders.)
"Preparing the magi-cannon," Anne reported.
"I will head out as well, if necessary." Reiko retrieved her dedicated weapon, Touka, from the onboard storage.
"Do you recognize those golems?" Jin asked the sisters.
"Y-Yes... those are Rock Giants. Only the Toying Clan can control them. I don’t understand why they would be here..."
"Perhaps someone there thinks it would be problematic if you two returned?"
Jin had meant it as a casual observation, but All-Creation’s expression turned grim as she fell into deep thought.