The air surrounding the Alchemist Guild tower had undergone a sinister transformation. No longer did the valley vibrate with the industrious, rhythmic hum of Miller's bellows or the reassuring, metallic clanging of the great forge. Instead, the atmosphere was thick with the cloying, oily scent of expensive Imperial lamp oil and a suffocating silence that felt like the stillness of a fresh graveyard. The Imperial pavilions, arranged in a perfect, geometrically precise radius around the base of the tower, looked like a blooming crimson fungus attacking a healthy, ancient oak.
Deacon stood at the head of the caravan, his hands steady on the reins, though his pulse hammered with the cold, calculated rhythm of a pre-op countdown. Every sensory detail was being filtered through his "Logistical Insight"—the Manhwa visual shorthand that caused his sapphire eyes to burn with a faint, crystalline glow. He saw the gaps in the Imperial sentry rotations; he noted the slight sway in the bound form of Father Marius atop the battlements; he felt the direction of the wind as it whipped the snow into fine, blinding eddies.
"The Twins are in position," Brandt whispered, his voice barely audible over the restless shifting of the horses. He was adjusting the lapels of his high-collared merchant's coat, checking the hidden glass vial of flash-powder sewn into his cuff. He held a small, polished silver mirror in his palm, angling it toward the riverbank. A single, sharp glint of sunlight reflected back—the signal. "The furnace flue is clear. They're entering the lower ducts now. It's a tight fit, Sarge. If the furnace hasn't cooled enough, they're going to be roasted before they hit the second floor."
Deacon didn't flinch. "They're professionals, Brandt. And Miller's insulation jackets are rated for the heat. Move the sledges forward. We need to draw every eye in that camp to the gate."
The "Iron Caravan" rolled forward, the heavy sledges grinding against the frost-covered path with a sound like a tectonic plate shifting. As they reached the outer perimeter of the Imperial camp, a line of Rose Guard knights stepped forward. They were a terrifying sight—a wall of burnished silver and crimson plumes, their "Rose-Iron" blades held in a low, thrumming ready position. The violet light of their weapons cast eerie, pulsating shadows against the snow.
"Halt, Lord Cassian!" Valois's voice boomed from the high balcony of the tower. The Herald looked down, his monocle glinting like the eye of a predatory insect. "You are remarkably late for your own audit. And I see you have brought... luggage. Is this the 'miracle' of the North? A few crates of wood and iron?"
Deacon pulled his horse to a stop, the beast snorting in the cold air. "I brought the survival of the South, Valois. Six Mark I Seed Drills, fully operational and contracted to the Oryn Marches. But I see the tower has a new tenant. Is this how the Emperor treats his most productive vassals? By holding their priests hostage like a common brigand?"
Valois leaned over the stone railing, his face twisted in a sneer of bureaucratic superiority. "Vassalage is a privilege, not a right, Cassian. The Church has concerns that your 'miracles' are nothing more than ancient, forbidden mechanica disguised as industry. We are here to 'purify' the process. Surrender the sledges, surrender the claimant Julian, and perhaps the Father will be allowed a quiet retirement. Refuse... and the Church will declare Oakhaven a blighted land."
While Deacon kept Valois's attention fixed on the gate with the practiced ease of a lead negotiator, the real battle was happening in the lightless, soot-choked arteries of the tower.
The Flue of Ash
Inside the tower's internal chimney—the primary furnace flue Julian had described—Pyper and Elan were navigating a vertical labyrinth of jagged stone and heat-warped iron. The space was a vertical throat, barely eighteen inches wide, coated in decades of carbonized soot that made every handhold a slippery gamble. The heat from the dying embers below rose in shimmering waves, making the air thin and acrid.
Pyper moved with the silence of a ghost, her silk-wrapped boots finding purchase on the narrow ridges of the masonry. She didn't use her hands for balance; she used "mechanical pitons"—small, spring-loaded spikes Miller had forged—to create temporary footrests. She moved upward inch by inch, her muscles screaming under the strain of the vertical climb, her silk mask filtering the worst of the ash.
Elan followed inches below her, his breathing perfectly synchronized with hers. They were a single shadow divided into two bodies. They reached the second floor—the level of the primary workshop. Through a narrow, iron-reinforced ventilation grate, Pyper saw a squad of Imperial soldiers. They weren't auditing; they were pillaging. They were hitting the gear-housing of the Mark II prototype with heavy mallets, trying to force open the "black box" mechanism Deacon had designed to shear its own pins if tampered with.
"Barbarians," Elan mouthed, his eyes flashing with a cold, protective rage for the machine he had helped build.
Pyper placed a gloved hand on his shoulder, a silent command for patience. Their target was the fifth floor—the High Library and the winch room. They bypassed the workshop, climbing past the storage levels where Miller's refined iron was stacked like bars of gold, until they reached the heavy stone ceiling of the Great Library.
With a silent, coordinated effort, they unscrewed the grate. They dropped into the room like spiders descending from a web, landing silently on the thick, dusty carpets. The room was empty, save for the flickering shadows of the hearth.
"Securing the upper winch," Pyper whispered, heading for the gears that controlled the main portcullis. "You get the Father. If he makes a sound, the Rose Guard will be on us in seconds."
The Psychological Siege
Back at the gate, the standoff had reached a fever pitch. Valois was losing his patience, his fingers drumming against the stone railing. He could see the defiance in Deacon's eyes—a look that didn't belong to a defeated noble, but to a commander who was counting down the seconds.
"Last warning, Cassian!" Valois roared, his voice cracking with the strain of his ego. "Surrender the boy, or the Father falls! The Rose Guard is ready to seize the caravan by force!"
"The boy isn't yours to take, Valois," Deacon said, his voice dropping into a low, terrifyingly calm register. He slowly reached for the hilt of his longsword, but he didn't draw it. "And Oakhaven isn't yours to audit. You wanted to see a miracle? I'll show you what happens when you try to cage the lightning of the North."
Deacon gave the signal—a sharp, piercing whistle that cut through the mountain wind.
Behind the sledges, Blake ignited the "Thunder-Claps." But these weren't the simple sound-bombs they had used in the woods. Miller had spent the last week refining the chemical mixture with magnesium shavings and copper salts. A series of brilliant, blinding flares erupted in the heart of the Imperial camp—vivid green and blinding white fire that turned the twilight into a searing, unnatural day.
The Rose Guard's horses, bred for war but never for this specific sensory assault, went into a frenzy. The knights struggled to maintain their formations as the air was filled with a deafening, rhythmic boom-boom-boom that vibrated in the very marrow of their bones. The magnesium light reflected off the silver armor of the knights, blinding them with their own radiance.
"Now!" Deacon shouted.
At that exact moment, the heavy iron portcullis of the tower—the gate Valois thought he controlled—began to groan. It didn't close; it rose with a sudden, violent speed, the internal counterweights triggered from within by Pyper's expert hands.
On the battlement, Elan emerged from the shadows behind Father Marius. His twin karambits flashed in the green light of the flares, severing the Father's bonds in a single, fluid motion. Before the Imperial guard beside Marius could even draw his breath to scream, Elan swept the man's legs and threw him over the railing.
"The Father is secure!" Elan's voice rang out over the chaos, sounding like a clarion call.
Deacon drew his longsword, the steel catching the flickering green fire of the magnesium flares. He looked like the "Stoic Duke" of a Manhwa legend—a figure of shadow and light, a commander of the impossible.
"Renna! Trios! Advance!" Deacon roared, spurring his horse forward. "Miller, Brandt—take the tower! No quarter for the Inquisitors!"
The militia, fueled by weeks of grueling training and a newfound, religious belief in their own technology, charged the Imperial pavilions. It wasn't a battle; it was a breach. The Rose Guard, blinded and deafened, found their "magical" blades useless against the sheer, coordinated violence of the Oakhaven Trios.
Deacon charged straight through the rising portcullis, his mantle billowing like a storm cloud. He looked up at the balcony, where Valois was backing away, his monocle falling from his face in a state of pure, unadulterated shock.
"You missed a detail in your audit, Valois!" Deacon shouted as he rode into the stone hall of his home. "Oakhaven doesn't just build plows. We build the men who use them. And today, the audit is closed!"
The "Infiltration of the Iron Cathedral" was over, but the tower was still a maze of enemies. Valois was retreating into the upper libraries, and the most dangerous part of the purge was about to begin. But as Deacon's boots hit the stone of his own hall, he knew one thing: Oakhaven had its teeth back.