The silence of the safe zone felt less like a sanctuary and more like a tomb. Chen sat cross-legged on the cold stone floor, his chest heaving with the shallow, rattling breath of a man whose body was fundamentally broken. The "Mana Circuit." Every time mana flickered through his veins, his muscles seized, and his capillaries threatened to burst.
He called up the System Shop. The blue interface didn't glow with a welcoming light; it was a sterile, unforgiving HUD that mirrored the harsh reality of his situation.
"Show me compatibility filters," Chen whispered, his voice hoarse. "Search parameters: Mana Circuit Stabilization and Foundation-level Body Tempering."
The list scrolled. Most were out of his reach exotic scriptures requiring "Heavenly Tribulation Lightning" or "Phoenix Blood." He needed something grounded. Something that worked from the inside out. Two entries pulsed with a dim, amber light, signaling high compatibility.
[Manual of the Iron-Bound Sinew]: A brutal Body Tempering method focusing on density over mass. Cost: 800 Credits.
[The Hollow-Aether Resonance]: A cultivation technique designed for those with high mana sensitivity but low physical tolerance. It treats the body as a flute hollowing out the impurities to let the energy flow without friction. Cost: 1,200 Credits.
Chen looked at his remaining balance. It would leave him with nothing. No potions, no emergency scrolls. Just his skin and the void.
"Purchase both," he muttered.
A flood of information shoved its way in. It felt like hot lead being poured into his ears. He didn't scream, but his jaw locked so hard he heard his molars grind.
The Iron-Bound Sinew wasn't a set of exercises; it was a metabolic rewrite. Chen stripped to his waist. He looked at his arms thin, trembling, and pale. To fix the weakness, he first had to destroy the existing structure.
He began the first posture: The Coiled Serpent. It required him to twist his torso while maintaining a deep squat, forcing his mana to pool in his lower extremities until the pressure became unbearable.
The pain started as a dull ache in his thighs. Within minutes, it sharpened into a thousand needles. The technique demanded he hold the position while manually vibrating his mana at a specific frequency to "shatter" the microscopic impurities in his muscle fibers.
He felt the first tear. It wasn't a clean snap, but a slow, agonizing pull. Sweat didn't just bead on his forehead; it erupted from his pores, stinging his eyes. His vision blurred. The System prompt flickered in the corner of his eye:
[Warning: Muscle fiber integrity at 40%. Continue?]
"Push through!" Chen spat, his voice a low growl.
He shifted to the second posture, The Stone Anvil. He collapsed forward, supporting his weight on his fingertips and toes, arching his back until his spine felt like a bowstring about to snap. Now, he had to draw the mana from his "Mana Circuit" and force it into his bones.
This was the part the manuals didn't describe in poetic terms. It felt like his marrow was boiling. The mana, usually cool and ethereal, turned into caustic acid when forced into the dense structure of his skeletal system. He could hear his own bones creaking under the atmospheric pressure of the technique. It was the sound of a ship's hull groaning in the deep ocean.
Every second was a marathon. His mind screamed for him to collapse, to just lie flat on the cold floor and sleep. But he knew that if he stopped now, the half-broken fibers would heal incorrectly, leaving him a permanent cripple. He had to finish the cycle.
As the physical tempering reached its peak, Chen transitioned into The Hollow-Aether Resonance. This was the bridge. If the first phase was the forging of the sword, this was the tempering in oil.
He sat back into a meditative pose, though every nerve ending was firing off alarms of agony. He had to take the chaotic, jagged mana currently wrecking his insides and harmonize it.
He closed his eyes and looked inward. His Mana Circuit looked like a series of glowing blue cracks across a dark landscape. They were beautiful, but they were jagged. They had "burrs" that caught the energy, causing the inflammation that was killing him.
He began the breathing cycle: four seconds in, hold for eight, exhaling for sixteen.
On the exhale, he guided a sliver of mana through the primary circuit in his chest. As it hit a "burr," he didn't try to bypass it. He used the Hollow-Aether technique to grind against it.
The sensation was akin to someone taking a metal file to his ribs.
He gasped, his rhythm breaking. The mana back flowed, hitting his lungs like a physical punch. He coughed up a spray of dark, stagnant blood the "impurities" the system spoke of. It wasn't glowing or magical; it was just waste. It smelled of iron and rot.
"Again," he whispered, wiping his mouth with a trembling hand.
He forced his focus back. He spent the next six hours in that dark room. He didn't move. To an outside observer, he looked like a statue. Inside, he was a battlefield. He was slowly, agonizingly smoothing out the interior of his own energy pathways.
He learned the geography of his own pain. He learned the difference between a "good" tear (growth) and a "bad" tear (injury). He learned to breathe through the moments when his heart skipped a beat because the mana pressure was too high.
When the sun finally began to bleed through the cracks in the safe zone's walls, Chen finally collapsed. He didn't fall gracefully. He slumped over, his skin covered in a layer of grey, oily grime that had been pushed out of his pores.
He lay there for a long time, listening to the thrum of his own heart. It was slower now. Heavier.
He looked at his hands. They weren't larger if anything, he looked leaner, more gaunt. But when he clenched his fist, there was no tremor. The "Mana Circuit" didn't flare up in a protest of agony. It sat beneath his skin, a dormant but disciplined river.
He checked his status.
[Body Tempering: Iron-Bound Sinew (Stage 1 - Initiated)]
[Cultivation: Hollow-Aether Resonance (Layer 1 - Completed)]
[Physical Condition: Exhausted / Stable]
[Mana Conductivity: Increased by 12%]
It was a small gain. In the grand scheme of the System, he was still a bottom-feeder. But it was a gain he had earned through sheer, unadulterated suffering.
Chen stood up, his joints popping like dry wood. Every muscle protested the movement, a dull, throbbing reminder of the night's work. He walked over to a small basin of water, looking at his reflection. His eyes looked older. The "cringy" illusions of being a chosen hero were gone, replaced by the cold realization that power in this world wasn't a gift.
It was a debt paid in blood and persistence.
He took a deep breath. The air felt clearer. The mana in the room felt less like a threat and more like a tool. He wasn't strong yet.
Chen wiped the grime from his face, picked up his gear, and looked toward the exit of the safe zone. The world outside was still a nightmare.