My Perfect Isekai: Pragmatic Protagonist, Progression Fantasy and Strategy

The heavy, iron-carved gates parted with a low, vibrating groan that rumbled through the basalt foundations of the sixty-ninth floor. The moment we crossed that monumental threshold, the space around us flickered violently. A fraction of a second later, the temporal pipeline of the return portal spat our silhouettes directly into the wet, suffocating, and terrifyingly dark biome of the seventh ten.

The descent to the seventieth floor of the Forgotten Necropolises welcomed us with a drastic, structural change in the environment.

The ground beneath our heavy boots was no longer the hard, sterile, and polished black obsidian of the previous floors. Instead, it gave way to cracked, slick slabs of wet basalt, between which a thick, steaming swamp lazily oozed. A heavy, impenetrable fog hung over the entire zone, and violet lightning continuously struck from the leaden sky, hitting the sharp stone spires and charging the ionized air with the choking stench of ozone, sulfur, and stagnant rot.

”Ale tu syf, szefie...” Kaede’s quiet, high-pitched voice echoed directly in my left ear, her tiny chitinous head poking out from beneath my high collar. She had spent the last several floors securely tucked away inside my new black coat, completely protected from the elements by her sapphire-slime powered armor. ”Krajobraz trochę jak z najgorszego zakończenia gier fantasy.”

”Pure environmental physics,” I replied with an easygoing, brazen chill, adjusting my collar with one hand while keeping both pushed deep into my coat pockets. ”The dungeon is getting desperate, darling. It is trying to choke our momentum with heavy moisture and barometric pressure.”

”Trochę jak w tej scenie z dziewiątego epizodu Star Wars, gdzie Palpatine odpalił cały swój prąd w niebo,” the spider giggled in our private Polish operational cipher.

”Gdzie dziadek wreszcie zebrał się do kupy i postanowił zdemolować galaktykę?” I tossed back in Polish with a relaxed, predatory smile.

”Dokładnie! Czyste, bezkompromisowe kino klasy B!”

We were standing on a brutal, subterranean training ground, but that brief, absurd exchange of pop-culture jokes made us feel as if we were back in a messy, cluttered room on Earth, holding gamepads and commenting on the media garbage. It was a perfect, brief reset of our combat tension.

But my sharpened, highly calibrated senses immediately caught a sudden shift in the vibrations at my side. I turned my head slightly.

Shnee was standing right next to me, her hand resting firmly on the hilt of her Celestial Silver rapier. Even though her newly reinforced, widened pathways were operating with a stable, quiet rhythm, the thick, toxic moisture of the swamp was beginning to compress the air around her lungs. Her porcelain cheeks were pale, and her breath was slightly shallow. She was fighting the pressure with her sheer, assassin’s pride, but her physical Vessel, unlike my reinforced machine, was reaching its current structural limits.

”Dave...” she whispered, her diamond eyes narrowing as she scanned the shifting shadows in the fog. ”The air here... it has a physical mass. It feels as if a heavy slab of iron is resting on my chest.”

”A typical layout design error,” I murmured coldly, stepping forward to block the direct path of the sulfurous wind. ”The system is simply increasing the density of the atmosphere to slow down our metabolic speed. It wants to drain our oxygen and force us to burn unnecessary calories on simple breathing.”

Without taking my hands out of my pockets, I focused my will, and a thin, sapphire current of my sapphire aura flowed into her pathways. The invisible, protective kinetic shell wrapped around her body, cutting off the toxic vapors and stabilizing the temperature around her to a comfortable, crisp eighteen degrees.

Shnee let out a long, trembling sigh of relief, her silver-white hair swaying in the artificial draft of my barrier, her gaze carrying a wave of fanatical devotion.

”Keep the pace, darling,” I ordered indifferently. ”We have an entire ten floors to clean to absolute zero, and I have no intention of letting some toxic mud spoil my coat.”

We pushed forward, implementing a relentless, machine-like speedrun through the seventy-first floor. The automated guards of this zone did not wait in clean, open arenas. They emerged directly from the bubbling, acidic swamps—hideous, mutated constructs formed from basalt, rotten wood, and glowing violet crystals of unstable mana.

They moved with a rwana, unpredictable speed, attempting to flank us and use the heavy fog to mask their trajectories.

But with my active perception and Kaede’s tactical pings, their camouflage was a joke. I mapped the entire cavern in a three-dimensional sphere within my mind, effortlessly calculating their lines of force and center of gravity.

When a giant, four-armed Abyssal Sentinel leaped from a basalt ledge, intending to crush me with a multi-ton stone axe, I didn’t even draw Orcrist.

I used plain common sense.

I caught the titan with point-blank telekinesis directly in the middle of its leap, completely neutralizing its kinetic momentum in a fraction of a millisecond. The colossal sentinel froze helplessly in mid-air, its plasma-infused axe sizzling uselessly against empty space. Before its primitive, system-bound brain could even process the fact that gravity in my presence was merely a loose suggestion, I stepped into its dead zone and delivered a powerful, full-body right hook.

My fist—reinforced by the raw physical density of my modernized Vessel—hit its polished brass helmet.

CRACK!

The collision produced a sharp, deafening snap of fracturing metal. The kinetic shockwave didn’t disperse across the surface; it penetrated directly through the armor, shattering its internal structural connections. The sentinel’s basalt neck exploded into fine gravel, its glowing violet core was instantly pulverized, and the entire giant collapsed into a harmless heap of black dust and falling loot before it even touched the wet ground.

”Dave! Two more approaching from the left!” Shnee’s voice cut through the damp silence as she glided forward, her rapier leaving behind beautiful, frozen arcs of ice.

”Neutralize them, darling,” I commanded coldly, already moving toward the descent. ”Do not waste your energy pathways on defensive barriers. Speed and efficiency.”

If you come across this story on Amazon, it’s taken without permission from the author. Report it.

The seventy-second, seventy-third, and seventy-fourth floors fell behind us in a matter of minutes. We moved like a sterile, relentless machine of destruction. I shattered their joints, broke their balance with minimalist kinetic nudges, and exposed their central cores. Shnee, moving with a feline, fluid grace that had been forged during our long, grueling sparring sessions, entered the gaps with surgical precision, her ice magic freezing their lifelines and leaving behind only the pleasant clink of falling drops.

By the time we reached the border of the seventy-fifth floor, the air had turned even more oppressive. The basalt floor was boiling, and from deep, jagged tears in the stone, orange-red magma began to ooze, turning the swamp into a boiling, toxic furnace.

My chest began to burn with a dry, sharp heat. The newly reinforced conduits of my Vessel were pulsing with a monstrous pressure. Pushing through several floors of extreme environmental resistance without a single pause was putting a physical bill on my biological frame. The sapphire current within my reactor was roaring at high speeds, and my human veins were protesting against the sheer throughput of my thirty percent power limit.

I ignored the warning. I adjusted the heavy pouch at my belt, which was jingling satisfyingly with violet cores, and took a deep, steady breath to oxygenate my blood.

”We are closing in on the boss room, boss!” Kaede warned tactically, her small legs tensing against my neck. ”The energy reading ahead is off the charts. It’s a massive, concentrated vortex of mana!”

”Good,” I muttered with a brazen smile, a predatory spark igniting in my eyes. ”The more resources they gather, the larger our starting capital. Shnee, prepare your rapier. Let’s see what kind of system error is guarding the gateway to the deep Hell.”

We pushed open the final, black iron gates of the seventy-fifth floor, stepping directly into a monumental, circular colosseum. In the very center, surrounded by a boiling lake of liquid magma, the floor of the dungeon rose with a deafening, seismic rumble that shook the basalt pillars to their core.

From the thick, sulfurous steam, the zone boss emerged.

The Abyssal Exarch.

The monster was a towering, four-meter monument of black iron, bone, and condensed violet mana. It did not possess a biological body—only an armor of dark metal that seemed to absorb the light around it, within which a hollow, pulsing void of energy swirled. In its massive, steel-clad fists, it held a monumental, double-handed Greatsword of Entropie, its blade vibrating with high-frequency spatial cracks that hissed against the air.

”A classic heavy armor model,” I noted indifferently, slipping my hands back into the pockets of my new coat as we stood on the edge of the platform. ”Designed to absorb Wide-area kinetic strikes and ground electrical charges. A very rigid, unoptimized approach.”

The Exarch roared, a sound wave so powerful it tore moss from the stone walls, and pointed its greatsword directly at my chest. The violet flames of entropy exploded from its blade, turning the oxygen in the arena into a smoking, toxic ash in a millisecond.

”Dave, the temperature is rising too fast!” Shnee shouted, her ice barrier instantly beginning to hiss and evaporate. ”My frost magic... it’s being suppressed by the ambient heat!”

”On pure logic, darling, temperature is merely the kinetic vibration of microscopic particles,” I explained calmly, my low voice effortlessly cutting through the roar of the magma. ”This violet shithead relies on entropy and heat transfer. If I cut off his medium, his entire power becomes nothing but a useless, cold piece of scrap. Watch this.”

I took a slow, deliberate step forward, a relaxed, brazen chill completely dominating my posture.

It was time to implement a new, clinical concept of spatial manipulation that I had been calculating in my spare time.

I focused my will. Instead of forming a wide kinetic shield, I compressed the space directly in front of us, creating a flat, multi-layered Vacuum Screen of zero density.

The monstrous wave of entropic fire hit the invisible barrier of my vacuum and... split silently, redirecting to the sides and crashing harmlessly against the basalt walls. Without air molecules to carry the thermal energy, the Exarch’s ultimate attack could not cross those few inches of empty space. I stood in the very center of the blazing inferno, my black coat not even slightly warmed by the heat.

The Abyssal Exarch froze for a fraction of a second, its glowing eye sockets flickering with a sudden, genuine system lag. It could not compute how its most devastating attack had been neutralized without a single drop of protective magic being cast.

”My turn, blockhead,” I murmured with a brazen smile.

I leaped forward, eliminating the kinetic friction beneath my boots. Using the full, monstrous speed of my Vessel, I glided across the boiling platform in a fraction of a millisecond.

I stepped deep into its dead zone, bypassing the slow, predictable swing of its massive greatsword.

I tensed my core and drove my right fist—coated in the black, light-absorbing armor of my Gōtai—directly into the central runic node of its chest, precisely where had mapped the structural heart of its energy pathways.

BOOM!

The impact resembled a high-voltage wire arcing against a steel post.

The concentrated kinetic energy, weighted down by the sapphire flow of my soul, bypassed the thick iron plates and exploded directly inside the Exarch’s void reactor. The spatial cracks within its armor collapsed inward, the violet mana detonated in an electrical implosion, and the four-meter giant literally shattered from the inside out, turning into a massive mountain of harmless gray ash and smoking ash that slowly settled onto the basalt floor.

A single, massive essence core, glowing with a deep, ruby-red light, fell into the soot with a quiet clink.

I stood in the center of the arena, extinguishing my Gōtai and letting the black coating smoothly absorb back under my skin. I reached down to collect the ruby crystal, sliding it into my pouch.

But the moment the combat adrenaline left my muscles, a sharp, white-hot needle of pain pierced directly through my chest.

I bent double, my hand clutching my chest as my breath became ragged and shallow. The sapphire reactor in my heart was spinning out of control, and my pathways felt as if they were being flooded with liquid fire. The physical cost of holding a hundred percent Gōtai and a vacuum screen on an unprepared, uncalibrated Vessel had finally presented its bill.

I coughed shortly, spitting an abundant stream of dark, metallic-tasting blood onto the black basalt beneath my feet.

”Dave!” Shnee was at my side in a millisecond, her porcelain face twisted in absolute terror as she supported my trembling shoulder. ”Your Vessel... your energy pathways! They are tearing! Your mana is destabilizing!”

”Boss! Shut down the engine, now!” Kaede’s panicked voice screamed in my ear. ”Your core temperature is spiking! The pathways cannot handle this throughput! You’ve overloaded the system!”

I wiped the blood from my lips with the back of my hand, a weak, but incredibly brazen and relaxed smile creeping onto my face.

”Calm down, girls,” I whispered hoarsely, my voice rough but stable. ”It’s just a hard physical limit. My engine is operating at its maximum capacity, but the delivery pipes are simply too narrow. A typical, unoptimized material choice. If I try to go any deeper into the eighth ten without a proper upgrade, my Vessel will literally disintegrate at the molecular level.”

I slowly straightened my back, feeling the sapphire reactor slowly stabilize as it began to repair the micro-tears in my conduits.

”We are making a tactical retreat,” I announced with cold determination, looking down at the stairs leading to the seventy-first floor. ”We return to the Golden Griffin. I must lock myself in my bedroom for a full, painful upgrade of my energy pathways. I need to widen these pathways and cement a stable thirty percent of my full power limit before we take another step down.”

Shnee looked at me, her eyes wet with tears but her stance instantly tensing with absolute, fanatical devotion.

”Understood, suwerenie,” she whispered, her hand tightening around her rapier. ”We will protect the base while you forge your new steel.”

”Taktyczny radar online, boss,” Kaede snuggled back into my ear, her voice carrying a rare, determined seriousness. ”Let’s get back. Elena and Luthia will secure the perimeter, and Mina will have a mountain of high-protein steaks waiting for your engine.”

We stepped onto the platform of the Sapphire Prism, and the space warped with a quiet, electric hiss, carrying our small, battle-worn family back to the safety of our base. The prelude to our true, absolute dominance had just ended, and the katorga of the upgrade phase was about to begin.