Chapter 347: The Eternal Gear

At the junction where the three central spires of Skyborne City converged, Astartes ushered away the passersby and unsealed a hidden door.

The thick anti-magic walls shifted and unfolded to reveal an immense lift, much like the teleportation arrays Wang Yu had once used to ascend to the higher tiers of the tower.

He stepped inside. Astartes's voice resonated through the chamber, steady and omnipresent. "Below lies the heart of Skyborne City. There, you will find the source of its power."

"The city's power core?" Wang Yu mused aloud. "Some kind of reactor? It must be a nightmare to maintain. Isn't there a significant risk of catastrophic explosion?"

Wang Yu brimmed with curiosity. He probed Astartes for more of the city's secrets.

The energy required to lift an entire metropolis into the sky had to be staggering. The standard alchemical cores he knew of, and even the reactor lodged in Iron King Bogul's chest, consumed vast reserves of mana stones and other types of fuel.

Yet from what Wang Yu had observed, the tribute Skyborne City demanded from kingdoms it protected rarely included fuel for energy production. Most involved alchemical consumables.

It seemed inconceivable that Skyborne City's technology, which had remained stagnant for years as a result of the Central Assembly's meddling, could be sustained by such a paltry sum of materials.

"That's precisely what I was about to discuss," Astartes said. "Skyborne City rests upon four colossal furnaces. They span nearly half the foundations underground, and are capable of transmuting alchemical matter into the power that sustains the city.

"Yet those furnaces usually lie dormant. To keep them active would indeed risk the kind of disaster you imagine: an uncontrolled surge or a ruinous blast that destroys the city's foundations."

Wang Yu frowned. If the furnaces were inactive, then how was the city supplied with energy at all?

"Then what powers Skyborne City? Surely not something like... a void engine?"

Wang Yu voiced his guess. If power were drawn from the void itself, it might make sense. After all, within the unfathomable gulf of the void very well might lie limitless energy.

"A void engine..." Astartes gave a wistful sigh. "A splendid idea. But no. When this city was wrought, such a technology was yet unborn. And afterward, when the Assembly halted all progress, no one could bring its development to completion. Still, I believe it will not be long before some research guild decides to study that idea further."

Wang Yu's intrigue only deepened. If Skyborne City weren't powered by furnaces or the void, then there could only be one possibility remaining.

"Then... is the city is driven by a curio?"

At that moment, the lift shuddered to a halt. Its doors unfolded with a groan of machinery and opened onto a plain stone corridor. At the far end stood a single door, Wang Yu's destination.

"Correct," said Astartes. "Did you know that my master, Merlin, was not the only one who had succeeded in creating a Machine Spirit? There was another."

"One of Merlin's disciples, Malfurion?" Wang Yu replied. Though he hadn't read about such an accomplishment in his alchemical texts, Sieg had once told him about it.

"Indeed. It is Malfurion's creation that sustains Skyborne City. Its name is the Eternal Gear.

"The curio takes the form of a vast gear with a radius of ten meters, forged of an unknown substance. When activated, it ignores all external interference and turns ceaselessly at a fixed speed.

"Any mechanism set within its teeth will be set in perpetual motion, so long as it does not break. This is how we have taken advantage of such a miraculous curio.

"The true core of Skyborne City was constructed around this curio. Special conduits channel the energy required to keep the metropolis aloft from it.

Astartes revealed the truth behind Skyborne City's flight to Wang Yu.

Wang Yu's eyes widened. "Then those four furnaces are merely reserves?"

"Precisely. We know too little about curios to trust them blindly, but that doesn't mean we shouldn't take advantage of them, either.

"If the Eternal Gear ever falters, the furnaces will suffice to keep the city aloft long enough to descend safely."

Wang Yu nodded. Skyborne City truly was a monument, a vessel into which untold centuries of knowledge had been poured.

"As a Machine Spirit, I oversee the city's workings, and the Assembly as well. But Malfurion's creation is... different. It believes that it is Malfurion herself."

Astartes's tone was tinged with disdain. "As such, its duties are limited. It governs only the city's core and one other matter—the archive of forbidden knowledge you seek.

"The authority remains mine, and if I grant you access, it cannot interfere. Still, if you can win its favor, it may save you much time in your search.... Though its temperament is eccentric."

Wang Yu caught the note of distaste in Astartes's words. Clearly, the two Machine Spirits were not on cordial terms.

"Shall I head inside, then?"

Wang Yu gestured to the door at the end of the corridor.

"Go on in. But remember that what lies within is only recorded knowledge from the minds of mortals. It is not the absolute truth. Do not let yourself be too deeply swayed by it. And know this: my authority is not unlimited. You may not remain for too long—perhaps a single day at best. Once my authority is exhausted, I shall summon you back."

With a casual wave to show that he understood, Wang Yu stepped from the lift. He strode down the narrow corridor, opened the door, and let the power of the Chariot seep outward in a watchful veil. What it sensed beyond the walls was a labyrinth of intricate machinery so complex it threatened to make his mind reel.

As he crossed the threshold, Wang Yu noticed that the interior design felt oddly out of place. It wasn't flawed—simply different from the Skyborne City he had come to know.

If the vast metropolis above was steeped in sleek lines and the austere gleam of modern alchemy, then this chamber felt as though it belonged to old tales: the archetypal study of a reclusive mage.

Before him was a worn wooden desk and simple, well-used stools. Rows of bookshelves were heavy with scrolls of parchment and grimoires penned on crackling vellum. Lamps glowed with the faint, uneven light of ancient mana-crystals. Strange implements, quaint and archaic cluttered what remained of the space.

"Just like my mental image of this world when I first arrived..." Wang Yu murmured to himself. Then, he shook his head briskly and turned toward the shelves, intent on finding what he sought.

"You there—what do you think you are doing?" Then came a sharp, cold rebuke. "Meddling with private documents is unforgivable behavior before Master's eyes. Stop at once, or I shall see you expelled."

Wang Yu's hand froze mid-gesture. Slowly, he turned toward the voice. A magical projection of a woman stood there. She seemed to be in middle age, her features plain, her expression taut with disapproval.

"...I have permission," Wang Yu replied evenly. "Astartes gave me permission to seek knowledge here."

He slid the tome he had just flipped through back into place: An Analysis of the Structures of Five Unique Seventh-Tier Spells. Its contents were formidable, but not what he most required. Still, once he finished his own research, he would make a copy for Avia and Sieg.

"Astartes, the Master's Machine Spirit?" The projection's face darkened. "And what right has it to allow intruders into my library? I am Malfurion, one of the Master's own disciples! This is my research and my discoveries—why should they be laid bare to strangers?"

Wang Yu noted the construct's growing anger, but did not reply to its questions.

"You're an alchemist, aren't you?" Wang Yu said abruptly.

He glanced at the shelves and retrieved a tome titled Singularity. Judging from its neighbors, it was likely a spellbook about an eighth-tier spell.

"Indeed."

"Then why do you have a spellbook on your shelves?"

"I practice both the arts of alchemy and wizardry. Is that a problem?"

"Of course not. Explain the contents of this spellbook to me, will you?"

"Explain it? Hmph. Very well..."

As Malfurion's projection accepted the book, she fell silent, her eyes roaming over the runes. Wang Yu paid her no further mind and returned to his search. Astartes had been clear: Malfurion might grumble, but didn't have the authority to bar him from looking around.

As for her dual claim of being a wizard and an alchemist, Wang Yu wasn't surprised. After all, Avia herself was the same. Yet Malfurion had always been recorded as an alchemist in the annals of history: also a magician, yes, but one who had accomplished little. There was little possibility of her being able to parse an eighth-tier spell.

Unbothered, Wang Yu worked quickly, going through shelf after shelf, conscious of his limited time. Somewhere among these volumes—or beyond them—had to lie what he sought: the secrets of space, the mysteries of the stars, and the truths of the Abyss.

At last the projection stirred again, her voice now edged with reluctant admission.

"...Very well. I cannot elucidate this spell. But that does not excuse you rifling through my shelves. Tell me: what exactly are you searching for?"

"I want to know the origin of abyssal creatures," Wang Yu said casually, eyes still scanning the spines. "How beings so feeble could once force the Five Races into such a bitter struggle and even slay gods in their wake."

Malfurion's eyes widened in surprise. "You truly do not know? Abyssal creatures hail from the stars themselves. And those pitiful husks you see now are but shadows, degraded countless times over from what they once were."

That revelation made Wang Yu pause. A new thought took shape in his mind. The shelves were not his only resource here. The knowledge bound within Malfurion's projection was just as precious—perhaps more so.

He turned, meeting her gaze with sudden intent. "Would you care to chat with me?"