The march back to the Ravine Outpost was a blur of exhausting, muddy steps. First carried the massive slabs of Behemoth meat, his reptilian footsteps sinking deep into the violet forest floor, while the Skirmishers prowled the flanks, eager to test their new venom on any scavenger bold enough to track them.

  Arthur walked in the center, cradling the heavy, steaming Behemoth heart in his augmented hands. It was the size of a rugby ball, wrapped in thick, cable-like veins. Even dead, the massive organ pulsed with a latent, localized heat.

  When they finally crossed the trench and stepped behind the safety of the palisade, the camp fell into absolute silence. The lesser Kobolds took one look at the sheer size of the harvested meat and dropped to their bellies in the dirt, recognizing the scent of an apex predator.

  Arthur didn't rest. He walked straight past the dying embers of the blast furnace and laid the massive cardiopulmonary core on his flat stone slab.

  He opened his interface.

  [Unallocated Stat Points: 10]

  This wasn't like fusing alien muscles to his arms or replacing his amputated legs. He was about to crack his own ribcage open, sever his major arteries, and rip out his own beating heart. The System’s magic would keep him alive during the Domain's active state, but the biological shock and the Stamina drain of splicing a Level 11 core into a human chest would be astronomical.

  He needed to survive the trauma, and his mind had to be a razor blade.

  Allocate 6 points to Constitution.

  Allocate 4 points to Intelligence.

  The rush of the stat allocation hit him like a physical blow. His skeletal structure groaned, the marrow in his bones thickening as his Constitution spiked to 16. His breathing deepened. Simultaneously, the blast of Level 24 Intelligence sharpened his vision until the world felt agonizingly clear. He looked at the massive Behemoth heart and instantly mapped the thick pulmonary veins and the massive aorta, mentally aligning them with his own fragile, human circulatory system.

  It was going to be a tight fit. The alien organ was too big. He was going to have to permanently expand his ribcage to house it.

  Arthur stripped off his blood-soaked, ragged shirt, tossing it into the dirt. His pale, human torso looked pathetic nestled between his thick, rust-red scaly legs and his disproportionately massive, muscle-corded forearms.

  He looked at the towering Vanguard. "First."

  The Elite Kobold stepped forward, the thudding in his chest echoing loudly in the quiet camp.

  Arthur pointed to the palisade, then to Second. "Lock the perimeter. If I pass out, you do not touch me. If I start screaming, you do not touch me. If anything breaches that wall while the Domain is active, you slaughter it before it makes a sound."

  First rumbled a deep, guttural acknowledgment. Second simply nodded, the violet eye in his chest already scanning the dark tree line.

  Arthur lay back flat against the cold stone slab. He placed the heavy Behemoth heart on his stomach. He raised his augmented hands and called upon his magic.

  [Initializing Surgeon’s Domain: Self-Modification Mode.]

  [Current Stamina: 100/100.]

  The golden, sterile light exploded outward in a ten-foot radius, pushing back the shadows of the Outpost. The silver tray materialized beside his head. Arthur grabbed the glowing scalpel and the heavy bone-retractors.

  [Proposed Material: Iron-Shell Behemoth Cardiopulmonary Core (Lv. 11).]

  [Integration Target: Host Cardiovascular System.]

  [Warning: Host ribcage volume is insufficient for Level 11 Core. Structural modification required. Survival rate: 12%.]

  [Cost: 85 Stamina.]

  Arthur’s eyes widened at the cost. Eighty-five stamina. That left him with exactly fifteen points to act as a buffer while his chest was wide open. One mistake, one hesitation, and the Domain would shatter, instantly killing him.

  He didn't hesitate. He brought the glowing scalpel to the center of his throat and dragged it straight down his sternum, slicing through his pale skin all the way to his navel.

  There was no pain yet, only the cold, clinical pressure of the System's magic holding the blood at bay. Arthur grabbed the heavy bone-retractors, locking them under the split edges of his ribcage.

  He gripped the cranks with his monstrous, Level 15 Dexterity hands.

  CRACK.

  Arthur bit down on his lip so hard he tasted copper as he violently cranked the retractors, physically snapping his own sternum and prying his ribcage apart like a set of double doors.

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  Arthur stared down into the cavern of his own chest. Bathed in the golden, sterile light of the Surgeon’s Domain, his human heart looked pathetic—a fragile, frantically trembling muscle struggling to pump blood through a body that was rapidly outgrowing it.

  His vision flickered. A sharp, icy pain lanced through his skull.

  [Current Stamina: 12/100. Critical threshold reached.]

  He had minutes, maybe less. If his stamina hit zero, the Domain would shatter, the magical stasis would break, and he would bleed out on the stone slab in seconds.

  He grabbed the glowing scalpel. There was no room for hesitation or fear. He treated his own body like just another piece of meat on the butcher's block.

  With terrifying, mechanical precision fueled by his Level 24 Intelligence, Arthur severed his superior and inferior vena cava. He sliced through the pulmonary artery and the aorta. The golden magic flared, instantly clamping the severed vessels and preventing a fatal hemorrhage, but the cold shock of having his blood flow magically suspended sent a violent shudder through his spine.

  He reached in, wrapped his thick, augmented fingers around his own human heart, and ripped it out.

  He tossed the fragile organ onto the silver tray without a second glance. He immediately grabbed the heavy bone shears.

  The Behemoth's cardiopulmonary core was too massive; it would crush his lungs if he just shoved it in. He needed to expand the housing. Arthur positioned the heavy shears against his lower ribs and violently snapped the cartilage connecting them to his sternum. He grabbed the severed ends of his ribs and physically bent them outward, permanently flaring his ribcage into a wider, deeper barrel shape.

  [Current Stamina: 7/100.]

  The edges of his vision went black. The icy cold in his skull spread down his neck.

  Arthur grabbed the massive, rugby-ball-sized Behemoth heart from his stomach. It was heavy, slick with black blood, and radiating a furnace-like heat. He hauled it up and shoved it directly into his widened chest cavity.

  It barely fit, pressing tightly against his lungs and the flared cage of his ribs.

  He dropped the scalpel and grabbed the spool of golden suture thread. This was the bottleneck. Splicing the thick, cable-like alien arteries to his fragile human veins required absolute perfection.

  His massive, chimera-muscled hands blurred. The Level 15 Dexterity took over, his fingers moving with impossible speed and stability as he drove the glowing needle through the Behemoth's thick aorta and fused it to his own. He stitched the pulmonary veins, tying off the golden knots with brutal, efficient yanks.

  Every time the needle pierced the alien tissue, a jolt of raw, hot electricity shot up his arms.

  [Current Stamina: 4/100.]

  He stitched the final vein, his breathing completely arrested. He was operating on pure, magically sustained borrowed time.

  Arthur dropped the needle. He grabbed the heavy bone-retractors still wedging his broken chest open and violently cranked them in reverse, collapsing his modified ribcage back together. He didn't bother with delicate internal sutures for the bone; he grabbed the glowing thread and rapidly stitched his pale skin and muscle shut in a jagged, ugly line down the center of his chest.

  [Current Stamina: 1/100.]

  He tied the final knot.

  The golden Domain shattered into dust.

  The magical stasis dropped instantly. For one agonizing, terrifying second, Arthur lay on the cold stone slab, entirely dead. His severed human heart lay on the tray, and the alien core in his chest was completely still.

  Then, the Level 11 Behemoth engine caught.

  THUMP-THUD.

  The sound was deafening. It didn't sound like a human heartbeat; it sounded like a pile driver slamming into the stone slab.

  A wave of absolute, searing agony exploded from Arthur's chest. The Behemoth’s heart pumped, sending a massive, high-pressure surge of Level 11, heat-infused blood violently rushing through his frail human circulatory system. His pale skin instantly flushed a dark, angry crimson. The veins in his neck and forehead bulged grotesquely, threatening to burst under the immense, unnatural pressure.

  Arthur arched his back off the stone slab, his jaws unhinging in a silent scream. His scaly, reptilian legs thrashed against the dirt, and his chimera arms clawed wildly at his own throat as his body was forcibly rebuilt from the inside out to handle the terrifying biological payload.

  [Integration Rate: 100%.]

  [Host Race Updated: Human (Chimera Variant - Stage 4).]

  [Biological disparity resolved. Massive Stamina regeneration unlocked.]

  [New Passive Skill Acquired: Behemoth's Furnace (Lv. 1).]

  Arthur collapsed back onto the stone, gasping for air.

  He didn't take normal breaths. His chest expanded with massive, deep pulls, sucking in huge volumes of the humid violet air. The heat radiating from his core was so intense that the sweat on his skin instantly evaporated into thin wisps of steam.

  He slowly pushed himself up into a sitting position.

  He looked down at his chest. His torso was no longer pale and frail. The flared ribcage had broadened his shoulders significantly, and thick, dense slabs of functional muscle had grown over his ribs to protect the massive engine pumping inside him. The jagged, ugly surgical scar ran straight down the center of his chest, a permanent reminder of the butchery he had inflicted upon himself.

  He clenched his fists. The heavy, aching fatigue that used to plague his human body was entirely gone, replaced by a deep, bottomless well of burning energy.

  The Surgeon had finally carved out his weakness.

  Arthur slowly stood up from the bloodstained stone slab.

  Before the surgery, just sitting upright after a major Stamina drain would have left him dizzy, his vision swimming with black spots. Now, the world was agonizingly clear. He didn't feel the phantom ache in his amputated legs, nor the heavy, dragging weight of his augmented arms.

  He felt invincible.

  The Behemoth's core pumped with a slow, terrifyingly powerful rhythm—THUMP-THUD. With every beat, a wave of intense, localized heat washed through his veins, supercharging his muscles and instantly vaporizing the cold sweat on his skin into thin, wisps of steam.

  Arthur reached down and picked up the heavy, acid-quenched cleaver resting near the slab.

  Hours ago, swinging the two-foot slab of alien iron felt like swinging a cinderblock. It had drained his human heart, leaving him gasping for air. Now, he wrapped his scaly fingers around the unhandled tang and lifted it with zero effort. The massive weapon felt as light and balanced as a standard surgical scalpel.

  He swung it in a blindingly fast, horizontal arc. The black metal sheared through the humid air with a sharp, violent hiss. His chest didn't heave. His heart rate didn't even spike.

  [Passive Skill: Behemoth's Furnace (Lv. 1) - Host Stamina regeneration is permanently increased by 400%. Host is highly resistant to environmental cold and physical fatigue.]

  Arthur smiled. It was a dark, predator’s smile. He was finally a complete chimera.

  He mentally dismissed the notification and opened the secondary alert that had been flashing in his peripheral vision since the Level 11 beast died in the mud.

  [System Feature Unlocked: Genetic Blueprints.]

  Arthur tapped the glowing blue text. The interface expanded, revealing a holographic, rotating anatomical model of a lesser Kobold. But the screen wasn't empty. Two distinct, golden folders hovered on the side of the display.

  He selected the first one.

  [Blueprint Saved: Deep-Stalker Variant (Scout)]

  [Required Materials: 1x Lesser Host, 1x High-Tier Optical Core.]

  [Description: The System has memorized the neural-splicing pathways required to graft a massive, central optical core to the host's spinal column. Future operations of this exact variant will require 50% less Stamina and execute automatically upon material insertion.]

  Arthur’s eyes widened. He immediately tapped the second folder.

  [Blueprint Saved: Venom-Skirmisher Variant (Shock Troop)]

  [Required Materials: 1x Lesser Host, 2x Keratin Spikes, 1x Toxic Gland.]

  [Description: The System has memorized the skeletal anchoring and vascular routing required to weaponize the host's forearms and salivary glands. Future operations of this exact variant will require 50% less Stamina and execute automatically.]

  This changed everything.

  Arthur didn't have to manually figure out the complex, agonizing surgery of splicing nerves and bone every single time he wanted to create a soldier. The System was learning his methods. If he provided the meat and the parts, the Domain would act as a biological assembly line.

  He could mass-produce an army.

  First stepped heavily into the clearing, the massive Vanguard's reptilian eyes locked onto Arthur's scarred, steam-radiating chest. The towering monster didn't growl; he lowered his head and dropped to one knee in the dirt, recognizing the sheer, dominating presence of the Level 11 apex core beating inside his master.

  Second and the two Skirmishers immediately followed, dropping to the ground in total submission.

  Arthur looked at his kneeling Chimera Guard, then out at the crude mud wall and the dark, suffocating tree line of the violet forest. Surviving was no longer the goal.

  "Get up," Arthur commanded, his voice rumbling with new, unnatural depth.

  The Guard rose in unison.

  Arthur pointed his black cleaver toward the massive pile of Behemoth meat First had hauled back, then pointed at the ten terrified, un-mutated lesser Kobolds huddled near the palisade.

  "Feed them," Arthur ordered. "We need them strong. Tomorrow, we stop hiding behind a mud wall. We are going back to the canyon, we are mining that Mana-Iron until the vein bleeds dry, and we are building a fortress."

  The Surgeon's Outpost was about to become a Kingdom.