A thunderous roar echoed from deep underground as a nine-layered gear assembly meshed, and the gate of the Celestial Palace Fortress crashed down, transforming into a gangway.

Most shocking of all, the main body of Guniu Mountain was separating from its foundation, revealing sixteen mechanical spider legs, each hundreds of feet tall. Heat vents at the leg joints spewed sulfurous steam, dyeing the night sky crimson for miles around!

The entire Celestial Craft City rose hundreds of feet on its spider legs, fully revealing the steam turbines once buried deep within its foundation. At its base, sixteen sets of annular boilers forged from Profound Steel formed the power core, each connected to Profound Steel transmission chains strong enough to haul a watchtower.

Outside the city walls, the bonfire-lit encampment of the Incense and Candle Sect, long since stationed there, suddenly erupted into a commotion.

The patrolling cultists stared in terror as the great mechanical city, which had remained dormant for nearly a thousand years, now stirred like a colossal steel spider shaking the earth from its back.

"Wh-what is that?!"

The Bone Marrow Cleansing Grandmaster, who served as a Great Dharma Protector for the Incense and Candle Sect, stared up in a daze at the mobile fortress striding toward them.

’Those damn blacksmiths, those practitioners of heretical arts... they actually built such a terrifying mobile city.’

The eight spider legs didn’t move in simple alternation; instead, they followed the walking patterns of the wooden oxen and flowing horses passed down from the Mo Family.

Each step landed with precision, avoiding the subterranean dark rivers. As the composite shock absorbers at the tips of the steel feet deployed, they converted the downward pressure into propulsive energy, blasting eighteen concentric shockwaves in their wake.

Xu Yunfan, utterly shaken, pressed himself against a viewport, watching the mountain-like steel city crush fields and rivers beneath it under the moonlight.

The pavilions and towers, once thought to be merely decorative, had all retracted to become combat modules. The Profound Steel Fortress extended honeycomb-like armor plates, and from the interlocking seams, dark cannon muzzles protruded.

"Unleash the Red Scale Fire!"

The roar of the Incense and Candle Sect’s Red Eyebrow Guardian was swallowed by the massive grinding of gears.

Several hundred trembling soldiers of the Incense and Candle Sect had just raised the Red Phosphorus Cannons recently delivered from Yu Jing State.

Just then, the walls of the Celestial Craft City flipped open, revealing thirty-six hundred bladed wheels. Steam-powered bricks of Profound Steel reconfigured themselves into a thousand-petaled iron lotus.

Scalding quenching fluid gushed from the lotus’s core, dousing the vanguard of the Incense and Candle Sect and melting them into a field of red-hot iron slag.

Cries and screams of agony erupted into chaos.

But they were drowned out by the immense roar of the moving Celestial Palace Fortress.

Deep within the Earth Veins, the clang of snapping chains resounded. Sixteen mountain-pillar-like Profound Steel spider legs slammed into the rock strata.

The entirety of Guniu Mountain collapsed amidst a storm of steam and sparks. As subterranean lava shot into the sky, it revealed a mobile Profound Steel Fortress, stretching for nearly a mile, now on the move.

"How does it feel?"

Zhan Yan stood with his arms crossed, his face filled with awe as he watched the scene unfold.

"When I first came to the Celestial Craft Cave and learned the entire city could move, I thought it was a fairy tale. Generations of Ancestral Masters and disciples of the Celestial Craft Cave poured their hearts and souls into its construction, all for this very moment."

After a long moment, Xu Yunfan pulled his gaze away, his heart still pounding.

’This is insane!’

"The Celestial Craft Cave... also has a Divine Weapon."

Zhan Yan’s casual remark made Xu Yunfan’s heart skip a beat. He remembered the shadow lurking beneath the Thunder Fire Pool when he had been forging the Profound Steel Mechanism Box a few days prior.

He instinctively looked down at the Celestial Craft Fortress beneath his feet. ’To move a city this massive... could it have been forged around a Divine Weapon as its core?’

The Celestial Craftsmanship Forging Record, part of the Celestial Craft Forging Technique, contained a relevant passage. It stated that a Ju Zi of the Mo Family had once personally built a mobile fortress, though it was nowhere near as enormous as the current one.

Back then, it was an era when the Primordial Spirit had not yet fully faded, a time when Secret Power was still abundant. A considerable amount of Extraordinary Secret Power still existed in the world.

This enormous Celestial Craft Fortress, however, was ninety-nine percent mechanical transmission structures, built on the blood, sweat, and tears of generations of engineers.

That night, no one in the entire Celestial Craft Cave slept.

A Celestial Craft Fortress a thousand years in the making naturally came with an endless list of complex problems.

"Abnormal wind pressure in the Xun Position!"

"The impellers in the Melting Furnace can’t handle the Earth Fire Stones! Get the Celestial Craft Department to replace the blades in the furnace, now!"

"Driveshaft in Xu District is overloading!" Han Qiushan, a Steward from the Mechanical Hall, was shirtless and covered in grease, his roars tinged with the sound of grinding metal. "Submerge the spare bearings in the Weak Water Coolant!"

"..."

Such a massive mobile fortress required an incredible amount of maintenance. The moment it started moving, thousands of problems surfaced. Nearly every disciple in the Celestial Craft Cave was mobilized, and even the weapon forgers from the Weapon Casting Hall were roped in to help.

Xu Yunfan, of course, was thrilled by the challenge and couldn’t resist lending a hand. With his knowledge of the Celestial Craft Forging Technique, even a basic understanding put him leagues ahead of the ordinary disciples of the Mechanical Hall.

Xu Yunfan made his way through a steam-filled corridor, his ears ringing with the shriek of gears and the shouts of disciples.

He stopped in front of the driveshaft in Xu District. The thirty-foot-wide Profound Steel shaft was emitting a piercing shriek, its surface glowing red-hot from the overload.

Xu Yunfan couldn’t help but marvel. ’With Profound Steel of this quality,’ he thought, ’a skilled Artifact Casting Master could definitely forge a weapon of the Lower-Grade Sharp Blade Level.’

The Celestial Craft Cave had occupied Guniu Mountain for a thousand years. In their thousand-foot-deep mines, they were short on many things, but Profound Steel was practically as common as dirt.

Before they left, the disciples of the Melt Gold Hall had even taken care to seal the mines, hoping they might one day have a chance to return.

Several Mechanical Hall disciples frantically submerged spare bearings in the Weak Water Coolant, but the cracks in the axle core continued to spread. Beads of cold sweat dotted Han Qiushan’s forehead, and his back was drenched.

"The Weak Water can only delay metal fatigue. It treats the symptom, not the cause."

Xu Yunfan spoke up suddenly, his fingertips brushing across the surface of the shaft. 𝚏𝗿𝗲𝐞𝚠𝕖𝐛𝗻𝗼𝐯𝕖𝚕.𝚌𝗼𝗺

The Thousand Machine Deconstruction effect of his Celestial Craft Forging Technique activated. An image of the transmission structure flowing within the axle core appeared before his eyes. He frowned; the internal structure had been twisted into a tangled mess by the overload, like a writhing nest of snakes.

If this continued, one of the spider’s leg segments would likely fail.

"Senior Brother Xu, this shaft uses the ’Four Symbols Suppressing the Mountain’ structure left by the Ancestral Master! We don’t dare touch it!"

One of the disciples cried out, sweating profusely with anxiety. But his words came too late; before his terrified eyes...

...Xu Yunfan had already snatched up the Thunderfire Qilin Hammer. Igniting the head of the hammer with the Shattered Jade Force of his Melting Gold and Forging Iron technique, he smashed it violently onto the Li Position mortise and tenon joint of the shaft connection.

"Are you insane?!"

Han Qiushan roared and charged forward, trying to stop him.

But as the hammer struck, sending sparks flying, the shaft—which had been on the verge of catastrophic failure—let out a clear, ringing cry, like that of a dragon.

The cracks had been forcibly sealed shut by the blow. The sight made Han Qiushan freeze mid-stride, his charge faltering.

Xu Yunfan pressed both palms against the shaft, the muscles in his arms bulging and straining the cuffs of his sleeves.

With an eruption of Blood Qi, he activated his Profound Turtle Carrying Mountain Strength. A peculiar power—the Armor-Stacking Technique Power—spread from his palms, channeling the rampant Shock Force down into the floor of the gangway.

The Wolf Spear creaked under the strain, but the intense heat radiating from the shaft quickly began to dissipate.