The morning air in Orario was crisp, but inside the training courtyard of the Hephaestus Familia, it felt like a furnace. Nyt stood in the center of the stone ring, his breathing ragged, sweat stinging his eyes. Across from him, the Captain of the Familia, Tsubaki Collbrande, stood with her arms crossed, looking remarkably bored.

  "Again," she commanded. Her voice was like a hammer hitting an anvil—solid and uncompromising.

  Nyt lunged. His movements were calculated, his HUD projecting a perfect vector of attack, but his body was a lagging processor. He swung a practice wooden sword, aiming for Tsubaki’s exposed flank. Before he was even halfway through the arc, Tsubaki shifted a mere two inches. She didn't just dodge; she moved with a physical efficiency that made Nyt’s "min-maxed" calculations look like child's play.

  With a flick of her wrist, she tapped his lead foot. Nyt tripped, his center of gravity shifting beyond the point of recovery. He hit the stone floor with a dull thud.

  "Administrator," Minerva’s voice echoed in his mind, cool and detached. "Your lactic acid levels are rising rapidly. Muscle fatigue is at 74%. However, I have recorded a 2% improvement in your reaction time compared to yesterday's session."

  "Two percent," Nyt wheezed, pushing himself up. "That’s... within the margin of error, Minerva. That’s not a breakthrough."

  "That’s your problem, Nyt," Tsubaki said, walking over to him. She didn't offer a hand to help him up; she waited for him to find his own balance. "You’re trying to 'calculate' a fight. You’re waiting for that little voice in your head to give you a green light before you move your muscles. By the time your 'data' reaches your brain, a Level 2 monster has already chewed through your neck."

  Nyt wiped sweat from his brow, his fingers brushing against the cold, matte-black surface of the First Paradigm gauntlet. "The data is correct, Tsubaki. My body is just... poorly optimized hardware."

  "Then let's upgrade the hardware," she grinned, a predatory flash in her eyes. "Drop the gauntlet. No space magic. Just you, your lungs, and the stairs of the Tower of Babel. We’re going to the Dungeon."

  The training regimen Tsubaki designed was a nightmare of mechanical stress and endurance. For the next two weeks, Nyt’s life was reduced to a singular loop: training, diving, and refining.

  Tsubaki didn't take him to the deep floors. Instead, she dragged him to the 5th and 6th floors the 'Upper Floors' where the monsters were weak enough not to kill him instantly, but fast enough to punish a slow reaction.

  "Don't use the 'Event Horizon'," Tsubaki yelled as a swarm of War Shadows ink-black, cat-like monsters circled Nyt. "Fight them with your eyes, not your magic! Learn the 'intent' of the strike!"

  Nyt ducked a lashing claw, his heart hammering against the Mechanical Core in his chest. Without his AI-assisted evasion, he felt blind. Every movement felt sluggish. But as the days passed, something strange happened. The "lag" between Minerva’s calculations and his physical response began to shrink.

  He was starting to develop "Muscle Memory" , the biological equivalent of a hard-coded script.

  "Minerva," Nyt thought as he parried a War Shadow’s strike with a standard iron shortsword. "Analyze the kinetic energy of my last parry."

  “Analysis: Efficiency has increased by 12.4%. You are no longer fighting the weapon's weight; you are using its momentum to augment your own strength. Suggesting a follow-up strike at a 45-degree angle.”

  Nyt followed the suggestion. The blade sliced through the monster’s core. It dissolved into ash, dropping a small, blue-tinted magic stone. Nyt didn't even look at it; his hand shot out, and the Void-Gate rippled open for a microsecond, vacuuming the stone into his repository without heaving a breath.

  "Not bad, brat," Tsubaki said, leaning against a dungeon wall. She had spent the last hour watching him struggle, only stepping in when a monster got too close to his vitals. "Your stats are still dismal for a Hephaestus smith, but your 'Mechanical Core' is doing something interesting. It’s... stabilizing your pulse?"

  "It’s act-acting as a secondary pump," Nyt panted. "When my heart rate... exceeds 160 BPM... the Core takes over... the circulatory load. It allows me to... maintain peak output... without cardiac arrest."

  "So you really are turning yourself into a machine," Tsubaki mused. "Well, if you're going to be an engine, you need better fuel. Let's go deeper. I need some Frog Obsidian from the 7th floor for my own projects, and you need to see if your 'Paradigm' can handle a real impact."

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  The 7th floor was a humidity-choked labyrinth of moss-covered stones and dripping water. It was the territory of the Killer Ants and the Almiraj rabbit-like monsters with horns that could disembowel a man in a single charge.

  "Minerva, structural analysis of the environment," Nyt commanded, his voice regaining its analytical coldness as he donned the First Paradigm.

  [Scanning... Atmospheric moisture is at 92%. The mineral composition of the walls indicates high concentrations of Frog Obsidian. Warning: High-frequency vibrations detected ahead. Large swarm of Killer Ants.]

  "Tsubaki, we have a swarm. Sector 4. Approximately thirty units," Nyt reported.

  Tsubaki didn't reach for her hammer. She stepped back. "Your floor, Clockwork Brat. Show me that the last two weeks weren't a waste of my time. Use everything."

  Nyt took a deep breath. He didn't feel the panic he had felt on his first day. Instead, he felt a strange sense of clarity. He saw the world in vectors. He saw the ants as moving data points.

  "Initiating Aetheric Blueprint: Recording Mode," Nyt whispered.

  As the first wave of Killer Ants surged forward, their hard carapaces clacking against the stone, Nyt held out his gauntlet. The ants weren't just fast; they had a collective intelligence, moving in a pincer maneuver.

  "Event Horizon: Vector Shift," Nyt commanded.

  The space in front of the lead ant didn't just expand; it rotated. The monster, caught in its own momentum, was suddenly diverted 90 degrees, slamming into its own kin. Nyt didn't stop there. He reached into the Void-Gate and pulled out a specialized tool he had spent the previous nights tinkering with: a high-frequency vibration emitter.

  He slammed the device into the ground.

  "Minerva, synchronize the emitter with the resonant frequency of their carapaces."

  “Frequency matched: 14.2 kHz. Pulse in 3... 2... 1...”

  A silent wave of sonic energy rippled through the corridor. To Tsubaki, it looked like nothing happened. But to the Killer Ants, it was a death sentence. Their hard shells began to vibrate violently, shattering like glass under the internal pressure. One by one, the ants collapsed, their internal organs turned to jelly by the resonance.

  "What... what kind of magic is that?" Tsubaki asked, her eyes wide. "There was no fire, no explosion..."

  "Resonance physics," Nyt replied, stepping over the twitching remains to collect the dropped obsidian. "Everything has a frequency at which it breaks. I just found theirs."

  By the time they returned to the surface, Nyt was carrying enough rare minerals to fund his research for a month. More importantly, he wasn't gasping for air. His body was starting to catch up to his mind.

  Back at the Hephaestus forge, the Goddess herself was waiting. She looked at Nyt at his slightly broader shoulders, his steadier hands, and the way he moved with a newfound "physicality."

  "Report," Hephaestus said.

  "He's still a brat," Tsubaki said, tossing a sack of obsidian onto the table. "But he’s a brat that can kill a swarm of ants without swinging a sword once. His 'Mechanical Core' is integrating perfectly with his Falna. Goddess... I think he’s ready for the next phase."

  Hephaestus looked at Nyt. "The next phase isn't about training, Tsubaki. It’s about interaction. Nyt, your Artifice is brilliant, but it's isolated. You’re building gear for yourself. If you want to truly master the 'Mechanical Core,' you need to see how your gear interacts with the 'Chaos' of other people."

  "The Chaos?" Nyt asked, tilting his head.

  "Adventure," Hephaestus smiled. "There is a young boy, a new adventurer from a tiny Familia. He’s been coming to our shop, looking at weapons he can't afford. He has a 'growth' similar to yours—rapid, illogical, and full of potential."

  "Bell Cranel," Nyt said, the name clicking in his memory.

  "I want you to observe him," Hephaestus commanded. "Go to the Hostess of Fertility tonight. He’s usually there with his Goddess. See if your logic can survive the most illogical element in Orario: a Hero."

  Nyt sat in his small workshop that night, the blue glow of his HUD illuminating the piles of obsidian and scrap metal. He looked at the First Paradigm gauntlet, which was currently undergoing a diagnostic check by Minerva.

  "Minerva, status of the 'Mechanical Core'?"

  “Integration level: 14%. Physical hardware (Your Body) is currently at 42% of required efficiency for Level 2 transition. However, Administrator, the data we collected from the 7th floor is invaluable. We can now forge the 'Acoustic Disruptor' and the 'Thermal Siphon'.”

  "Good," Nyt said, leaning back in his chair. "But Hephaestus is right. I’m building a closed-circuit system. I need to see how external variables affect my gear."

  He thought about the anime he had watched, the boy with the white hair and the "Liaris Freese" skill. In his previous life, Nyt would have called it a 'glitch' or 'hacked code.' Now, he saw it as a unique dataset.

  "We’re going to the tavern, Minerva. We’re going to meet the White Rabbit."

  “Shall I prepare a 'Social Interaction' script, Administrator?”

  Nyt smirked, a rare, genuine expression of amusement. "No, Minerva. Let's wing this one. I want to see if my physics can explain a 'Miracle'."

  As he stood up, he felt the Mechanical Core pulse in his chest, a steady, rhythmic beat that felt less like a machine and more like a heart. He was no longer just a scientist in a strange world. He was an Artificer of Orario, and the first chapter of his 'Simulation' was finally over.