Mass Production Breakthrough
Seojun Im looked down at the ledger on the workbench. The densely packed numbers made his head spin. Doyokshini's total order was 200 units. He'd delivered 10 in the first shipment. Staying up nights lately, he'd hammered out 30 more, but handed one off to Park Cheolwoo of Silver Lining Guild for testing. Current stock: 29. To hit the promised second shipment of 45, he needed 16 more right away.
No problem there. Sixteen was manageable with a few days of hard labor. The real headache came next. Third shipment: 145 units. Even with plenty of time, no way he could forge that many solo. The forging process—heating the iron, pounding it, folding it over and over—devoured time and stamina like a beast. He'd be lucky to touch any other commissions while cranking those out.
Got to change the process. His gaze shifted to the molten metal blazing in the furnace. Doyokshini's specs were straightforward: no fancy techniques needed. Just heavy and tough. And maces and armor weren't structurally complex anyway. Solid striking heads from a single billet, thick iron plates for the breastplates.
Casting it is. Molds, pour the metal, let it set. Inevitable for mass production. He'd planned to try after the second batch, but time to accelerate. He'd mixed Yin Iron and steel before. All that was left was making the molds.
Seojun pulled wood planks and fine clay from the storage shed. He opted for sand casting. Metal molds would eat too much time and cash; clay was efficient. First, he needed a pattern. He stripped the chain off an existing mace and separated the head from the handle. Placed them in a wooden frame, packed it with clay, and rammed it down tight. He pounded it with a wooden mallet until the clay hardened. Carefully extracted the mace, leaving a perfect cavity. Drilled a pour hole for the metal and a vent for gases.
Now pour. While prepping the mold, he'd melted Yin Iron alloy in a small furnace. Seojun lifted the crucible with tongs. The alloy spat red-hot light. He poured carefully into the sprue.
Glug.
The thick liquid sucked into the mold. He stopped once it reached the vent. After enough time passed, he dismantled the wooden frame. The hardened clay crumbled away, revealing an iron club inside. Still steaming with heat. He picked up the cast mace with tongs. Shape matched the original perfectly. But he gave the surface a light tap with the hammer.
Thud.
Forged ones rang solid and clear; this was duller.
Lower density. Unlike forging's hammering that densified the grain, casting left looser structure and lower density. Why factory mass-prods always felt cheap. Some added partial forging or fancy alloys to boost quality.
Fine for people. Even hunters—stronger than normals—would find it plenty. But Doyokshini's troops were dokkaebi, with strength beyond imagination. Not enough.
Failure. Couldn't ship like this. Compromising quality went against a blacksmith's code. Keep the casting speed, but match forged durability.
Tweak the alloy ratio? Or heat treatment? Seojun headed to storage, pondering. It was stuffed with Yin Iron from Doyokshini, but there was also a box of kaeyi byproducts in the corner. Gifts from clients so far.
Only useful one's... Haran's egg. Specifically, the shell. Hard as steel with killer fusibility.
This could handle volume too. Material supply was key for big orders. Haran said anytime.
Let's try. Seojun brought out a spare egg shell—from shield-making slime work. Dumping it raw would just make impurities. Needed to powder it for full melt. He set it on the anvil and smashed it hard with the hammer into bits. Dumped the fragments into a steel mortar. Tried grinding by hand—no dice.
"Hoo..."
Normal strength wouldn't cut it. He triggered kaeyi transformation. Vision grayed; power surged into his arms.
Crunch, grind.
A creepy sound like chewing steel. The shell resisted stubbornly, but kaeyi grip won. After a wrestle, it powdered white.
Good enough. Into the small furnace crucible with the Yin Iron and steel melt. Added the powder right away.
Sizzle—
Kaeyi stuff clashed hard. White foam rose; the melt turned dark crimson. Ominous-looking, but too soon to judge. Carefully poured the crimson metal into the mold. Felt different—higher viscosity, denser maybe. Cooled slower too, clinging to the heat. Broke the frame after time. Out came the second casting. The sheen was different from the start. Tongs to anvil; hammer down.
Clang!
Clear metallic ring, no tempering needed. Dense as forged.
"Success."
A smile crept across Seojun's face. The shell had perfectly filled the metal grains, maxing cohesion. Tough enough for dokkaebi roughhousing. Certain now, no delay. Full mass production mode.
He made multiple molds—not just for maces, but armor too.
The forge's rhythm shifted. Clay-packing and pouring overtook hammering. Mold, pour, cool, break. Could be monotonous, but Seojun loved it. The output piled up visibly faster. Main flow: cool castings in breezy spot. Reheat in furnace, temper in diluted egg ghost byproduct slime solution. Polish surfaces, oil against rust, assemble parts. Done. Completed maces and armor stacked rapidly in the forge.
Five days passed. Sun dipped; thick darkness settled. The forge air grew heavy. Doyokshini appeared without warning.
"Long time no... see?"
Her greeting cut off; jaw dropped. No trace of her usual dignity—just a shocked girl's face. Her eyes fell on the gear piles.
Volumes beyond the first shipment.
"What might all this be?"
Doyokshini asked in a dazed voice. Seojun peeled off his gloves, answering flatly.
"Your ordered goods. Inspect the quality yourself."
Doyokshini drifted to the stack like mesmerized. Picked up a mace. Heavy weight, solid feel. No quality drop from the last batch. If anything, a fiercer aura. Quick eye-count.
"Over... a hundred easy."
Precisely 115. Impossible in five days. Solo blacksmith, handling kaeyi materials at that speed? Beyond reason.
"Even lofty kaeyi smiths from distant lands couldn't manage this."
"Power of science."
"Science... Humans are remarkable."
Doyokshini admired the armor too, unable to hide awe. Other kaeyi smiths could cast, but the speed gap crushed them. Old beings stuck in outdated ways.
"In barren lands, great kaeyi smiths might yet rise. My troops could arm swiftly."
Her face lit up. A chance to reverse dire straits.
"If it pleases you, I have a question."
"Thou art qualified. Ask freely."
"Can humans wield kaeyi-forged gear safely?"
Seojun asked cautiously, recalling recent events. Park Cheolwoo, Silver Lining Guild master, raved about the mace against kaeyi in a dungeon and requested more—but he'd refused over concerns.
"Depends on the item."
"Pure Yin Iron for now. But mixing like in these maces and armor—kaeyi stuff in?"
"From this land's ancients, no doubt."
Doyokshini spoke knowingly. But unperturbed, she replied calmly.
"Gear used by kaeyi versus made from kaeyi—vast difference. The former, even ordinaries endure. The latter, only the exceptional bear the aura—and even then, long use brings no good end."
Doyokshini looked up, meeting Seojun's eyes.
"Unless it be thee."