Morning mist curled around the Iron Fortress's looming silhouette. Chen Yuan gazed at the city‑state built atop a titanic spinal column of bone, the click‑clack of gears echoing through the valley. Massive femurs upheld the three‑story-high iron gates, which bristled with rusted cogs that hissed scalding steam each revolution. In the eye sockets of the "Old Ruler" skull above the lintel, two kerosene lamps glowed like embers.
[High‑danger energy readings detected]
[System suggests: avoid the main gate; enter via eastern drain]
"Easy for you to say—what if that drain houses some beast?" Chen Yuan muttered, resting a hand on his corpse‑puppet "Old Jin." It trudged stubbornly beside him, its ragged bandages gleaming where mechanical parts had been grafted on. "I should've gotten decent prosthetics in Mist‑Hidden City. Now I'm hauling around a walking bandage frame—hard to stay inconspicuous."
At the east drain, thorned iron bars blocked entry. As Chen Yuan cut through with his Bone‑Fang Blade, metal shrieked against steel. Fortunately, the system prompted:
[Rust‑ward rune detected. Infuse bone‑toxin energy to dispel.]
He pressed bone‑toxin from his fingertips into the corroded metal. Rust flaked away, revealing a narrow gap. "Why didn't you say so earlier? Almost wrecked my blade." He rubbed his aching wrist as Old Jin clambered through, its mechanical joints squeaking—a custom upgrade from the Mist‑Hidden City workshop to better mimic Iron Fortress prosthetics.
Inside, the fortress pulsed with ceaseless industry. Streets were paved with bone shards and gears; buildings displayed steam‑driven limbs in window racks, mechanical arms clattering trophy trophies of monster parts. Rounding a corner, Chen Yuan spotted a girl in goggles crouched by a toppled automaton. She hammered a wrench into its shattered actuator, her short golden hair flecked with oil. Twelve screwdrivers dangled at her belt.
"Nika?" he asked. She was the "Wrench Maiden," adopted daughter of Hector, Iron Fortress's leader.
She glared up, blue eyes like molten glass. "What are you staring at? If you need your limb fixed, go to Workshop No. 3—stop getting in my way!"
"I… need to refill my gear oil." Chen Yuan gestured at Old Jin's elbow—an exposed cog whirring erratically. "His power core's been jamming."
Nika's gaze sharpened. She tapped the gear with her wrench; it rang with an unexpected cloud‑and‑thunder pattern. "That's an ancient magic‑path rune—no mechanist here carves that. And why does your "prosthetic" feel alive? There's still bone‑toxin staining."
Chen Yuan's muscles tensed; he slid a hand toward his Bone‑Fang Blade. The system flashed:
[Core secret at risk of exposure—use Silence Talisman immediately]
"Don't panic—I mean no harm." Nika's lips curved into a grin as she produced a mechanical pocket watch etched with the same cloud‑and‑thunder motif. "My father found similar parts in the rotwood—he said they're relics of ancient cultivators."
The watch's hands twitched toward Old Jin, buzzing softly. As Nika's mechanical arm touched the puppet, he heard faint incantations woven into the gear‑work—the Iron Fortress's unique "Mechanist's Way," driving automata with runes.
"Follow me," she said, hefting her wrench. "There's an abandoned workshop in the back alley. We'll need… special methods to fix that limb."
Inside the dusty workshop, rusted gears and monster bones lay everywhere. On the central bench rested a half‑built mech‑cadaver, its chest cavity cradling a pulsing monster core. Under lamplight, Nika's brows knitted in concentration.
"So tell me—what is this? A mechanist's limb, or… something else?"
He hesitated, then unwound Old Jin's head bandage to reveal the black bone‑toxin sigils etched on its temple.
"I found fragments of corpse‑refinement lore in the rotwood's ruins. I tried grafting prosthetic machinery onto a corpse‑puppet. But the core kept rejecting the corpse's life force."
Her eyes lit.
"Life‑force versus mechanical energy colliding—yes! My father tried powering prosthetics with monster cores and they just blew up." She pried off Old Jin's shoulder cog; sparks of blue flame flickered as it hit the floor. "If you bind the joint with bone‑refinement runes, then guide the power with Mechanist's Way sigils—look!"
She pressed a bronze plate inscribed with runes around the elbow joint. At once, ghostly death‑qi traced the glyphs and the stiff limb began to move—flexing, even making a fist.
[System detects resonance between mechanist runes and magic‑path art]
[Unlocked Skill: Automaton Core Fusion (can integrate mechanical prosthetics to enhance corpse‑puppet agility)]
"You really know your stuff," Chen Yuan thought—though he outwardly beamed with excitement. "Where'd you learn that?"
"The Mechanist's Way here was born from ancient cultivator texts," Nika replied, dusting her goggles. Her gaze settled on the cloud‑and‑thunder gear in Old Jin's chest. "My father's been trying to fully restore that path. Unfortunately…" Her voice trailed off as an alarm shrieked outside—interlaced with bestial roars.
"Bone‑shatter beasts!" Nika's face paled. "They can pulverize prosthetic gears!"
They dashed outside to see three rhinoceros‑like brutes trampling down the street, bony spikes erupting from their hides with each step, shattering gears from every building. Steam‑powered guards fell apart against their bulk.
"Old Jin—engage!" Chen Yuan activated Automaton Core Fusion. Old Jin glowed blue as the Bone‑Fang Blade's runes synced with its gears, and the swing of its blade crackled like a sonic boom. When the first beast's spike snapped, Chen Yuan saw a gear‑shaped bone seed embedded in its spine.
[Special core detected: Mechanist Bone Seed (stores both death‑qi and mechanical energy)]
His eyes gleamed. He reached out; searing energy flooded his palm in a refinement far smoother than ever before. The bone seed dissolved into azure light, harmonizing death‑qi and gear rhythms.
"Watch out!" Nika shoved him aside as a beast's barbed tail grazed his scalp, gouging a chunk of wall. Her mechanical arm twisted grotesquely, but with a triumphant grin she raised her wrench. "Your prosthetic outclasses the fortress guards'!"
He didn't answer—Old Jin was already locked in the final beast's grapple. Remembering the jade slip's "Bone‑Banner Summoning," Chen Yuan used the Mechanist Bone Seed as a focus. Rusted gears from the workshop whirred to life, encircling Old Jin in a gearstorm.
"The ancient mechanist art… 'Thousand‑Blade Gearstorm!'" Nika gasped. "My father's notes mention this!"
As the storm shredded the last beast into scrap, its core hurled toward Chen Yuan. At that moment, the system chimed:
[Realm breakthrough achieved: Qi‑Refinement Level 4 (0/300)]
His corruption, remarkably, dropped by 2%—the purity of mechanist energy purging chaos‑qi. He watched the scales on his hand fade.
"So mechanist arts can neutralize corruption?" he marveled. "System, you should've told me sooner."
After the battle, Nika led him to the Iron Fortress's power core: a bone‑furnace built around an Old Ruler's heart, hundreds of mechanical tentacles siphoning monster cores into steam power.
"My father says this was his bargaining chip with the Abyssal Temple—monster cores for their non‑aggression pact," Nika said quietly, her mechanical arm brushing her palm. "But lately the core's pulse has grown erratic—like something is trapped inside."
Bone‑Vein Resonance flared in Chen Yuan's mind—he "saw" a complete magic‑path cultivator skeleton buried deep within the furnace, its chest bearing the same cloud‑and‑thunder bone seed as his jade token. The system warned:
[Residual artifact soul detected—recommend immediate resonance]
"Your father's deal may have invited a greater threat," Chen Yuan said, gripping Nika's shoulder. "That core holds an ancient cultivator's remnant soul. The Abyssal Temple wants to resurrect something."
Nika's blue eyes widened. "How do you know? Father never said…"
"Because I've seen similar ruins." Chen Yuan drew the jade token; its sigils glowed in the furnace's light. "Iron Fortress's mechanist tradition stems from magic‑path lineages—twisted by Cthulhu cultists."
Heavy footsteps thundered above, the grind of bone‑gear limbs signaling Hector's approach. Nika's face paled.
When Hector strode through the doorway, Chen Yuan finally grasped why he was called "Father of Gears." The lord's lower half was a mass of bone‑gear machinery, a translucent core beating within his rib‑cage, arms morphing into rune‑etched mechanical tendrils.
"Outsider." Hector's voice clanged like rusted gears. His tendrils lashed toward Chen Yuan. "You smell of rotwood—and of energies beyond Cthulhu's gift."
Chen Yuan tightened his grip on the blade. He noticed black ooze seeping from the tendril tips—signs of chaos‑qi erosion. The system's warning burned on his display:
[Detection: near‑demigod‑class presence—recommend immediate withdrawal]
"Father—he's here to repair the core!" Nika interjected, positioning Old Jin's arm between them. "He understands ancient mechanist magic—he can fix it! If not him, who?"
Hector's tendrils hesitated as his core's pulse quickened.
"Mechanist magic… You've seen Azure Bone's ruins?"
"Azure Bone?" Chen Yuan feigned confusion even as his heart skipped a beat—that was the First Patriarch's name. "In the rotwood cave—I saw gears etched with the same cloud‑and‑thunder."
Hector's tendrils snatched Chen Yuan's wrist, mechanical force threatening to crush bone. In agony, Chen Yuan let the jade token cloak his aura—transmuting his magic‑path qi into mechanist energy.
"Good." Hector released him. Tendril‑ooze vanished. "Iron Fortress needs mechanists like you. Nika, take him to the underground workshop to restore the power core—fail, and you two will become new cogs for the core."
Once Hector's footsteps receded down the gear‑driven corridor, Chen Yuan realized sweat soaked his back. Nika's hand trembled as she hoisted her wrench.
"Don't worry—Father's harsh, but he doesn't kill lightly… unless you truly botch the job."
The workshop's great door creaked open. Before them lay the power core in full: the ancient cultivator's skeleton bound by pentagram‑shaped chains, each chain linked to the fortress's gargantuan gears. The system spelled out his task:
[To free the chains, destroy five cultist runes—recommend using Bone‑Fang Blade's Rending Wounds effect]
"Taking the blame again, aren't you?" Chen Yuan thought, feeling the unique potency the Mechanist Bone Seed lent his blade. "But it's fine—finding materials here and freeing an ancient soul is well worth it."
As gears were stripped away, Nika dismantled the outer locks. Steam hissed as her mechanical arm rotated with practiced grace.
"What do you need from me?" she asked.
"Cover me." He stared at the nearest rune—a tentacle‑shaped sigil carved into a rib. "If I start chanting strange words, don't stop me—that's ancient mechanist incantation."
He didn't tell her the true source—his modified Myriad‑Bone Soul‑Refinement verses. When his Bone‑Fang Blade sliced through the first rune, the skeleton cried out without sound, and gears whirled through his mind alongside a venerable voice:
"At last, someone to unbind this old bones…"
"Azure Bone, the Patriarch?" Chen Yuan thought, heart racing—but kept cutting. "We'll talk once these five chains are down."
Above, Hector's tendrils hovered at a monitoring gear. He withdrew a metal box etched with tentacles—inside lay a half of a cloud‑and‑thunder jade token exactly matching Chen Yuan's.
"Lilith of the Shadow Circle reports a aberration fusing corpse‑puppets and machines in Mist‑Hidden City," Hector whispered. The box clicked in reply. "Never imagined it would come to our doorstep. Now, to the Abyssal Temple… a grand gift awaits."
As Chen Yuan severed the last chain, the Iron Fortress roared with grinding metal. The ancient cultivator's skeleton rose, eyes blazing blue‑gold flame. Chen Yuan's system blazed with a new notification—the patriarch's true legacy unlocked. In this city of gears and runes, a revolution in the Mechanist's Way was about to begin.