The glowing light-energy cuffs binding the wrists of Zulfa, Naya, and Captain Danu were loosened the moment they passed through the main barrier gate. Emerging from the narrow, suffocating colonial corridor, their eyes were greeted by a sight that shattered the logic of modern human reasoning.

They now stood within a colossal crystal cavern stretching as far as the eye could see. The soaring cavern ceiling was choked with clusters of purplish-blue luminescent crystals radiating a soft glow, illuminating the entire subterranean ecosystem like thousands of stars in a night sky. At the center of the cavern flowed a crystal-clear underground river reflecting the crystalline light, flanked by interwoven organic architectural structures—ancient stone buildings merging harmoniously with the roots of primordial giant trees and glowing metal circuitry.

"Incredible..." Naya whispered unconsciously, her stride slowing in sheer awe. She craned her neck, studying the magnificent geometric structure of the cavern. "This place... this isn't just a regular underground cave. It's an entire, intact civilization."

Kaelen, the Arkian leader who had escorted them, strode ahead without looking back. He glanced briefly from the corner of his eye and grunted softly.

"You thought humans were the only race that knew how to build a civilization? That city of yours on the surface, modern or not, is merely a miniature replica standing upon the magnificent ruins left by our ancestors."

Zulfa walked beside Kaelen, his eyes continuously tracking the cavern support pillars pulsing with pure energy. As an engineer, his technical instincts flared at the mechanical marvels surrounding them.

"I see those optical circuit cables," Zulfa said, pointing toward a nearby pillar, his voice sounding enthusiastic despite his status as a captive. "But the energy flow isn't coming from conventional electricity or fossil fuels. That... that's pure mana wave filtered through a solid mechanical medium."

Kaelen halted, turning to look at Zulfa with a raised eyebrow. The Arkian leader's cold expression softened slightly in surprise. "You can see it? Most surface humans see nothing more than rock and scrap iron when they set foot down here."

"Because I'm an engineer," Zulfa answered firmly, locking eyes with Kaelen's optical lens. "In my world, we call advanced technology science. But what I'm seeing here... this is the seamless fusion of precise physics and ancient magic. You've integrated ancient sorcery into precision mechanics."

"That is called Aether-Tech," Kaelen stated with a more authoritative tone, leading them deeper into the main headquarters hall. "To our kind, magic and mechanics are not two separate things. Magic is the life force, and mechanics are the vessel to control it. Aethel Corp's technology up top? That is merely a cheap, savage imitation of the foundational Aether-Tech principles they stole from this city's ruins archives decades ago."

Captain Danu, marching in the rear rank alongside the resistance fighters, listened closely to the explanation. "If that corporation stole your technology to build their energy harvesting system, that means they're accelerating the destruction of this city's entire bedrock strata, right?"

"Precisely," Kaelen answered grimly. "Every time the seal valves are forced to drain Aether energy illegally, this cavern's structural support weakens. If you hadn't come to smash their main control room yesterday, that micro-quake would have collapsed half the city district."

They were led to an open balcony overlooking the Arkian research center. Down below, Arkian scientists were repairing crystal engine components using hand tools glowing with plasma light.

Zulfa stood transfixed before an open console, studying the workings of an energy purification machine responding to the operator's mental touch. His curiosity as an engineer eclipsed his fear as a prisoner. Unconsciously, he stepped closer to the console, reaching out to brush his finger against the pulsing crystal surface.

"Don't touch it!" an Arkian guard warned sharply.

Yet that warning was instantly defied by a bizarre anomaly. The moment Zulfa's fingertip brushed the crystal surface, the primordial machine neither exploded nor rejected him. Instead, the crystal flared brighter, harmonizing its wave frequency with Zulfa's heartbeat before projecting an intricate three-dimensional holographic blueprint into the air.

Kaelen and the Arkian elders witnessing the event froze in place. They exchanged looks of utter disbelief.

"His genetic frequency... it unlocked the core Arkian device completely unaided," one of the Arkian elders murmured in awe. "How could a human of the Architect's bloodline naturally resonate with our machinery?"

Amidst the silence blanketing the research deck, Naya—standing a few paces behind Zulfa—suddenly felt something strange inside her coat pocket.

An antique flat metallic disc inscribed with gear wheels and astrological needles—an ancient time compass artifact she had salvaged from the central bureaucracy archive room the day before—began vibrating violently in her pocket.

"Eh...?" Naya murmured softly, digging into her coat pocket with a trembling hand.

The moment she pulled the ancient compass from her pocket, the object radiated a blinding golden glow. The compass needle spun wildly inside the artifact, then whipped around, vibrating fiercely toward Zulfa's jacket pocket—where his father's audio cassette tape and Mr. Darma's master memory chip were safely stowed.

Naya's eyes blew wide, staring down at the compass in her hand before shifting her gaze back to Zulfa, who still stood frozen before the crystal console.

"Zul..." Naya whispered tensely, holding up the brightly glowing compass before Zulfa. "This compass... this thing reacts mysteriously every time it gets close to your jacket pocket!"