My Perfect Isekai: Pragmatic Protagonist, Progression Fantasy and Strategy

The industrial heart of Crossgard hummed with a low, rhythmic vibration that echoed through the granite foundations of the Iron District. Smoke of varying hues—grey from coal fires, copper-red from alchemical furnaces, and violet from raw mana refining—drifted lazily across the jagged, smog-choked skyline. Yet within the high, reinforced walls of the Ancient Foundry, the air was surprisingly crisp, filtered by the invisible, kinetic-slime mesh that Dave had woven across every vent, archway, and window slit.

The main hall of the foundry was a monumental structure built during the early mining era. Three tiers of heavy basalt walkways overlooked a central pit dominated by a three-story industrial furnace forged from heat-resistant, runic iron. Decades of abandonment had left the heavy machinery covered in thick layers of soot, oxidized copper, and dried slag, but the structural bones were indestructible, engineered to withstand the monumental pressures of high-yield refining.

Dave stood on the central walkway, his hands loosely tucked into the deep pockets of his long, black coat. His golden-sapphire Pyrite Core hummed with a quiet, frictionless rhythm at the center of his chest. The newly unlocked second-level reactor maintained a steady, self-sustaining flow of high-density energy through his widened, reinforced pathways.

”Czujniki czyste, szefie!” Kaede’s cheerful voice pinged in his left ear from her perch on his shoulder, using their native Polish operational cipher. ”Trzy poziomy pod ziemią uszczelnione! Szafirowy śluz złapał kontakt ze starym rdzeniem pieca. Przewody są całe, a żyła magmy pod nami jest aktywna na osiemdziesiąt procent! Możemy odpalać ten kloc w każdej chwili!”

Shnee walked gracefully along the upper gallery, her Celestial Silver rapier resting lightly at her hip. Her cool, icy aura created a subtle, eighteen-degree thermal buffer that offset the oppressive heat rising from the district’s lower vents. She glanced down at the massive iron furnace with a faint, sharp smile, her eyes assessing the reinforced basalt masonry.

”The structural integrity of this building exceeds the guild halls we passed near the main gate,” Shnee noted, her voice smooth and measured. ”The ancient merchants built this place to withstand internal alchemical explosions. With your kinetic mesh in place, it is virtually impenetrable from the street level.”

”Street level is easy to defend,” Dave replied calmly, his analytical eyes scanning the intricate ironwork of the central flue rising fifty meters toward the vaulted ceiling. ”The real test of a fortress is how it handles the vermin that don’t use doors.”

Dave took a slow, measured step forward, gliding toward the control platform overlooking the furnace pit. With a casual flick of his wrist, he unbuckled a mental valve in his energy conduits. A thin, concentrated thread of Sapphire Slime shot from his palm, diving straight into the main fuel manifold of the industrial furnace.

The moment the slime touched the cold, dormant runic conduits, the Pyrite Core in Dave’s chest unleashed a controlled, three-percent impulse of golden-sapphire electrical current.

THUM-THUM-BOOM!

The massive iron furnace roared to life. A brilliant, sapphire-blue flame erupted within the sealed combustion chamber, instantly vaporizing thirty years of accumulated soot and rust. The runic conduits along the outer walls ignited in sequence, glowing with a stable, azure light as the thermal energy from the deep magma vein was drawn upward and converted into clean, pressurized work power.

The entire foundry vibrated with renewed purpose. Heavy piston housings settled into rhythm, pressure gauges stabilized at optimal parameters, and the central anvil platform glowed with an even, white-hot readiness.

”O ja ciechrzrz!” Kaede chirped, her small spider legs tapping rapidly against Dave’s collar. ”Szefie, ten piec chodzi lepiej niż nowe reaktorskie klocki w stolicy! Runiczny prąd jest czysty jak łza! Mamy własny, suwerenny warsztat! Żadna gildiarska menda nie ma tu wstępu!”

”The furnace is online,” Dave said softly, his analytical mind registering every pressure gradient and thermal flow within a hundred-meter radius. ”Now we clean out the lingering trash.”

High above the main hall, inside the fifty-meter vertical exhaust chimney that vented out toward the slate roof, a shadow shifted.

It was not a natural shadow cast by the furnace glow. It was an active, mana-crafted illusion—a cloak of weaving darkness worn by an elite infiltrator of the Shadow Syndicate. For twenty minutes, the assassin had been descending the inner brickwork of the chimney, using specialized suction claws and shadow-meld spells to slip past the foundry’s upper defenses.

The infiltrator, known within the Syndicate’s lower rings as Nightshade, was a veteran of forty-two silent liquidations. Sent by the Syndicate’s regional warden to assess the arrogant newcomer who had defied the Iron Guild and purchased the Foundry with raw silver, Nightshade had expected an arrogant noble or a brash mercenary chief.

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Instead, he had just witnessed a man ignite a dormant, three-story industrial furnace with a single, casual flick of his fingers, without a single incantation, staff, or alchemical primer.

Nightshade’s pulse spiked violently. This isn’t a spellcaster, the assassin realized, his body pressed flat against the soot-stained brickwork inside the dark flue. He didn’t cast fire magic. He pressurized the manifold with pure kinetic force and high-density electrical discharge. The energy efficiency is impossible... I need to report back to the Warden immediately.

Nightshade slowly began to retract his limbs, preparing to melt back up through the top of the chimney into the night air.

”You’re going the wrong way,” a flat, calm voice echoed directly inside the assassin’s eardrums.

Nightshade froze. The voice didn’t come from below—it sounded as if the speaker was standing directly beside him in the cramped, two-meter-wide vertical shaft.

Before the assassin could activate his shadow-dispersion charm, the air inside the chimney changed dramatically.

The natural atmospheric pressure instantly multiplied by a factor of ten. The column of air within the flue transformed into a solid, unyielding hydraulic piston. Nightshade was slammed backward against the soot-stained bricks with the force of a falling anvil, his breath exploding from his lungs in a ragged, suffocating gasp.

CRACK!

His specialized suction claws snapped like brittle twigs under the sudden, immense gravitational load. The shadow-meld spell coating his leather armor dissolved instantly, torn apart by the absolute, light-absorbing density of Dave’s kinetic field.

Down in the main hall, Dave hadn’t even turned around. He stood by the central anvil platform, resting his right hand lightly on the cold iron surface while his left hand remained casually tucked into his coat pocket. His Pyrite Core hummed at a barely audible fourteen-percent load.

”Szefie! Mamy gościa w kominie!” Kaede called out with a predatory grin. ”Jeden cwaniaczek z Syndykatu Cieni! Próbował zejść szybem wentylacyjnym i myślał, że nikt go nie zauważy!”

Shnee didn’t even draw her rapier. She simply stepped to the base of the chimney, her cold blue eyes looking up into the dark flue with an expression of mild, disdainful boredom.

”Shall I liquidate him, Dave?” Shnee asked quietly, her voice echoing smoothly in the vaulted chamber. ”A single frost needle through the throat will ensure his permanent silence.”

”No need to waste the ice,” Dave replied smoothly. ”A dead spy only tells his master that we’re aggressive. A broken spy tells his master that we’re untouchable.”

Dave closed his right hand into a loose fist.

Inside the vertical chimney, fifty meters up, the kinetic field contracted with surgical precision. The air pressure didn’t crush Nightshade’s ribs—Dave’s control was far too refined for crude slaughter. Instead, the kinetic force locked every joint, muscle, and tendon in the assassin’s body, paralyzing him completely while leaving his nervous system fully conscious.

Then, a thin thread of golden-sapphire lightning zipped up the chimney wall, wrapping around Nightshade’s throat like a glowing, humming collar.

The assassin’s eyes widened in sheer, unadulterated terror. The energy humming against his carotid artery wasn’t standard elemental lightning—it was the ultra-dense, refined output of a Pyrite Core. A single micro-impulse would instantly boil his brain inside his skull before his heart could complete another beat.

”Listen carefully, rat,” Dave’s voice resonated through the glowing collar with terrifying, crystalline clarity. ”You are going to walk back to your Warden. You are going to tell him that the Ancient Foundry is now sovereign territory under my sole jurisdiction. If another shadow enters this chimney, I will not stop the kinetic pulse at your collar. I will trace the mana thread back to your guild house and flatten the entire block.”

With a subtle flick of Dave’s fingers, the immense pressure inside the chimney vanished.

Nightshade plummeted ten meters down the shaft before the glowing sapphire thread caught him by the collar, arresting his momentum instantly and tossing him roughly out through the top vent onto the cold slate roof of the foundry.

The assassin lay on the roof for a long moment, gasping frantically for air, his leather armor ruined and his shadow charms completely fried by the residual static charge. He didn’t look back. He scrambled across the slippery tiles on all fours, diving into the dark alleyways of the Iron District like a terrified rodent.

Down in the hall, Kaede giggled softly, doing a tiny victory spin on Dave’s shoulder.

”Szefie! Koleś chyba właśnie pobił rekord świata w sprincie po dachach!” the spider chirped happily. ”Syndykat Cieni dostanie raport z pierwszej ręki. Pancerz potargany, honor w gruzach, a przekaz czysty jak kryształ! Teraz wiedzą, z kim mają do czynienia!”

”The message is delivered,” Dave said, stepping away from the anvil as the furnace hummed at a perfect, stable frequency. ”Now we begin the real work of the workshop.”

Dave motioned to the heavy basalt workbench near the furnace pit. From his spatial storage, he withdrew the rare material reserves harvested from the fifty-ninth and sixtieth floors—four dense ingots of liquid silver preserved in crystal canisters, three blocks of runic obsidian, and six glowing purple cores from the dungeon’s high-tier golems.

Shnee stepped closer, her eyes glittering as she observed the raw materials. ”The purity of this silver exceeds anything available in the merchant markets.”

”Because it wasn’t refined by merchants,” Dave said calmly, setting up the alchemical casting molds. ”We are going to alloy this liquid silver with runic obsidian to forge a new structural lining for your Celestial Silver rapier and the internal conduits of my coat. Higher thermal conductivity, zero kinetic resistance, and three times the mana throughput.”

Kaede scurried down to the workbench, her small eyes scanning the layout with professional satisfaction. ”Szefie, z takim zaopatrzeniem i własnym piecem nasze wyposażenie będzie miało klasę wyższą niż gwardia cesarska! Żaden kupiec w Crossgardzie nie podejrzewa, czym dysponujemy!”

Dave looked at his reflection in the polished surface of the central anvil. Deep within his pupils, a golden-sapphire light burned with absolute, unyielding clarity. His modernized Vessel hummed in perfect resonance with the Pyrite Core.

”We build our own alchemical reserves, free from guild pricing and merchant taxes,” Dave said coldly. ”In three days, we return to the gate. And when Kaelar comes to collect his tax, he won’t be dealing with a squad of mercenaries. He’ll be dealing with an empire.”

The industrial furnace roared, casting long, triumphant shadows across the granite walls of the Sovereign Workshop.