The battle in the western sector of the Interstellar City was far from being confined to that area alone.
The clash between Demeter's and Shiomi's Noble Phantasms inevitably rippled across the entire Interstellar City.
Along other routes, while the city's attention was completely drawn toward Shiomi and the others, Artoria led the Mobile Investigation Squad carefully along the outskirts, passing through the southern region of the Interstellar City as they discussed where to go next.
The massive floating island that carried the entire city began to shake violently.
"What's going on… an earthquake?"
Caught off guard, Sakura lost her footing and fell to the ground. Almost instinctively, she deployed a defensive Barrier, bracing herself for collapsing structures or falling debris that might follow the tremor.
"No, that's not it."
Artoria looked solemnly toward the western side of the Interstellar City. Closing her eyes, she focused on the source of the overwhelming magical fluctuations.
"This power… it's Tenkei's Noble Phantasm, 'The Poem of Creation and Rebirth.'"
"Father?"
Sakura took Gray's outstretched hand and stood back up.
Cold sweat ran down Barghest's face.
"…That Noble Phantasm… Is Tenkei-sama planning to knock this entire Interstellar City out of the sky and into the sea?"
"I don't think that's his intention," Gray said thoughtfully. "If everything is going according to plan, he should be fighting a goddess right now."
"Demeter, or Aphrodite?" Barghest muttered, unable to decide.
Artoria shook her head as well.
"I can't be certain either. But our top priority right now is to use the fact that Olympus is completely focused on Tenkei and the others to search for the advance team—"
She checked on Sakura one more time and was about to lead them onward when Barghest suddenly raised his sword.
"Who's there!"
His voice, sharp with vigilance and authority, startled a boy and a girl who had been approaching from a nearby alley.
Their clothing was identical to that of the Interstellar City's residents. There was no doubt they were locals.
"…You don't look like people from Olympus," the boy said warily. "Are you… from that Chaldea?"
The earlier broadcast had echoed throughout the entire Interstellar City. Artoria and the others had heard it as well.
"Did you hear Zeus's divine decree and come to fulfill your duty as children of the gods by hunting us down?" Artoria asked.
She stepped forward, positioning herself in front of Sakura and Gray, her grip tightening around the invisible Holy Sword.
She could sense it clearly. The boy and girl possessed magical energy on par with Servants, no different from the rest of the city's inhabitants.
They were unquestionably high-grade humans, perfectly matching the warning Demeter had previously left for Shiomi.
Even if it were only two opponents, this was not a situation where they could afford to lower their guard.
"Wait. If you're from Chaldea, then there may be a misunderstanding between us."
This time, the girl stepped forward to explain.
"Macarios, don't be so tense."
"…You're right."
Macarios realized he had overreacted and relaxed slightly, though his expression remained serious.
"Not… enemies?" Sakura asked softly, still unsure.
The girl introduced herself.
"My name is Adele. I'm Makarios's older sister. We're members of the 'God-Shattering Alliance.' After hearing Zeus's divine decree and receiving news that the western defense corps was fighting an unknown enemy… we guessed that Chaldea had arrived."
"In short," Artoria said with a nod, "the ones fighting against the Interstellar City's defense forces, and possibly even the gods themselves, are our allies. Then what exactly is this 'God-Shattering Alliance'?"
"If you came from Atlantis, you should have heard about it," Adele replied. "Some Servants, with the sacrifices and support of many comrades, managed to infiltrate Olympus. They formed the 'God-Shattering Alliance.' We're residents of Olympus who chose to join them."
"You?"
Artoria was visibly surprised.
She had always assumed that the people of Olympus were all devout believers of Zeus. She never expected to hear something like this.
"Since you're residents of Olympus, why are you helping the hostile 'God-Shattering Alliance'… no, why are you helping Proper Human History?" Sakura asked, getting straight to the point.
Adele gave an apologetic smile. "That's a bit complicated to explain. This isn't a place we can stay for long. If you don't mind, please come with us to the 'God-Shattering Alliance' base."
"Since you're not engaged in combat, you must be a squad assigned to other operations," Macarios said, stating the obvious. "If your objective is to search for the vanguard of Proper Human History's Servants…"
He didn't finish the sentence. The people from Chaldea all understood what he meant.
"What should we do?" Gray asked Artoria.
Sakura lowered her voice. "It could be a trap."
"Stay alert. If it is a trap, we'll fight our way out," Artoria replied quietly. "Either way, we don't have any leads right now. Let's follow them and see."
Barghest nodded in silence.
"Then please, lead the way," Artoria said.
The siblings nodded together, turned around, and began walking ahead.
Along the way, they avoided the main streets, moving through the shadows cast between towering buildings.
There were no longer any active pedestrians on the streets. Instead, large forces made up of soldiers and magical beasts could be seen marching toward the western sector of the interstellar city.
"Looks like Dad and the others are doing pretty well," Sakura murmured.
"But that just means all of Olympus's pressure is being pushed onto Teacher and the others…" Gray said worriedly.
Artoria felt the same, but she held back her thoughts and instead reassured the girls. "Have faith in Tenkei and the others."
While quietly exchanging their thoughts, they followed the siblings who called themselves members of the 'God-Shattering Alliance,' descending deeper into Olympus's underground levels.
Natural light gradually disappeared, replaced by artificial illumination.
All four of them raised their guard to the highest level.
The tremors shaking Olympus had already stopped. They had no way of knowing whether the battle was temporarily deadlocked or already over.
At last, they arrived at an area that resembled a factory. A massive mechanical gate blocked their path.
Adele entered something into a device beside the door, and the gate slowly opened.
The two stepped aside and gestured for them to enter. Artoria went first, with the others following closely behind.
The instant they passed through the doorway, a sharp spike suddenly shot toward them. Artoria knocked it aside with her sword, and the other three immediately shifted into combat readiness.
"Who… are you?" a familiar yet weak voice demanded, then abruptly turned to shock. "Father… King?"
"Saber?"
Sakura covered her mouth, letting out a soft gasp.