The retreat of the Duke's heavy cavalry was not a victory to be savored, but a data point to be analyzed. Kael stood upon the northern bastion, observing the distant dust cloud settling behind the retreating knights, already calculating the escalation timeline. By repelling a noble house's personal guard with standardized, long-range fire, Kael had stripped away the Duke's ability to use intimidation or low-level harassment. The next engagement would not be a probe; it would be a formal military mobilization. The Duke would return with siege engines, pavise shields to negate the crossbow fire, and a numerical superiority designed to overwhelm the five hundred citizens through attrition.
Kael recognized that the standardized heavy crossbow, while revolutionary for his infantry, was insufficient for stopping heavy siege towers or battering rams. He needed a heavier tier of defensive weaponry that could project lethal kinetic energy far beyond the current perimeter. He initiated the Ballista Project, a systematic plan to design and manufacture static, high-power defensive engines that could be integrated directly into the barony's stone bastions. This was not a pursuit of military glory, but an extension of industrial engineering applied to the physics of ballistics.
The design phase took place in the central office of the Iron Works, where Kael utilized the high-quality parchment and mapping tools to draft the schematics. He rejected the traditional, torsion-based catapult designs common in the south, which relied on the unpredictable tension of twisted sinew or rope—materials that were difficult to maintain in the damp, ashen climate of the frontier. Instead, Kael designed a Massive Steel Spring Ballista. The power source would be a dual-leaf spring system forged from the same high-grade coastal iron used for the crossbow triggers, but on a massive scale. .
Hektor was tasked with the most difficult metallurgical challenge yet: forging the massive, tempered iron leaves that would serve as the spring. These components had to be flexible enough to be drawn back by a heavy winch but resilient enough to snap forward with thousands of pounds of force without shattering. Kael supervised the tempering process personally, utilizing the optimized Kiln to maintain a precise, sustained temperature over thirty-six hours, followed by a controlled oil-quench. The process was logged with the same obsessive detail as the initial harvest, with every minor fracture resulting in a total recalculation of the carbon-to-iron ratio.
While Hektor forged the springs, the expanded Contingent labor force was redirected to structural siege preparation. Kael identified the inherent weaknesses in the existing stone walls—areas where the original masonry was thin or prone to vibration. He ordered the construction of internal buttresses made from recycled stone and the high-density refractory bricks. These reinforcements were not just for defense; they were designed to serve as stable, vibration-dampening platforms for the new heavy ballistae. Kael utilized the Mapping Project data to calculate the optimal firing arcs for each engine, ensuring that every approach to the northern and eastern gates was covered by at least two overlapping fields of fire.
The ammunition for the Ballista Project was as standardized as the engines themselves. Kael designed a heavy, iron-shod bolt nearly six feet in length, weighted precisely to ensure a stable flight path over four hundred yards. He directed the Dependent group to produce these bolts in high volume, utilizing the standardized jigs to ensure every tip was balanced and every fletching was identical. "Precision at range is not a matter of luck," Kael explained to the assembly teams. "It is a matter of removing every possible variable in the manufacturing process. If the bolt is identical to the one before it, the engine will hit the same mark every time."
The social impact of this preparation was one of grim, focused industriousness. The five hundred citizens, now fully aware of the Duke's impending return, did not panic. They had seen the heavy cavalry broken by their own handiwork, and they saw the massive iron springs being hoisted onto the walls as an extension of their own labor. The literacy program continued, but the curriculum now included technical manuals on ballista maintenance and fire-control mathematics. Every citizen-soldier was trained to calculate distance based on the geometric markers Kael had painted onto the stones of the killing fields.
By the time the third heavy ballista was mounted on the central northern bastion, the barony's defensive posture had been fundamentally altered. Ashfall was no longer just a settlement; it was a calibrated weapon. Kael conducted a final live-fire test, targeting a wooden frame he had placed four hundred and fifty yards away—a distance that would be occupied by an enemy's command tent or siege camp. The heavy bolt, launched with a singular, deep metallic thrum that vibrated through the stone of the wall, shattered the target instantly.
The chapter ends with Kael standing beside the newly mounted engine, looking out over the dark horizon. He received a report from Fennis via the trade route: the Duke had officially petitioned the regional governor for a "Peacekeeping Mandate," a legal pretext to mobilize a thousand-man levy and three professional mercenary companies. The storm was coming, but Kael had used the intervening weeks to build a system capable of weathering it. The industrialization of Ashfall was complete; now, the survival of the system depended on the efficiency of its iron heart.