Neon lights flickered violently above the Underground Sector, casting broken shadows across wet brick walls.
The air reeked of cheap alcohol, rust, and illegal potions. This was the Black Market—a lawless zone where Hunters, mercenaries, and criminals traded without taxes… or questions.
Arthur moved through the crowded alley, his black cloak hiding his academy uniform—and his identity.
He ignored the flashy stalls. Glowing swords. Colorful elixirs. Worthless distractions.
He already knew what he wanted.
At the end of a dead-end street, he pushed open a creaky wooden door.
A bell chimed softly.
The shop was small, dusty, filled with strange artifacts and monster remains.
Behind the counter sat an old man with a scarred face and a mechanical right eye. A thick cigar burned between his lips.
"We don't buy slime cores or rat tails, kid," the old man grunted without looking up. "Try the recycling center if you're broke."
Arthur didn't respond.
He stepped forward… and placed a faintly glowing green orb on the counter.
Thud.
The mechanical eye whirred.
The old man froze. The cigar slipped from his mouth and hit the floor.
"…A Corrupted Ghoul Core," he muttered, all arrogance gone.
He leaned closer, inspecting it with a magnifying lens. Dark energy swirled densely inside the orb.
"Fully intact… Level 8 Elite Boss…"
His mechanical eye lingered on Arthur a second too long—sharp, calculating… dangerous.
"How did someone like you get this?"
"I found it," Arthur said flatly. "Are you buying or not?"
A brief silence.
In the Black Market, asking too many questions was a good way to die.
The old man swallowed.
"Official price is 5,000 credits," he said, opening a heavy safe. "But here? No questions, no records. I take a cut. 4,500."
"Deal."
No hesitation.
Five hundred credits meant nothing compared to staying hidden.
The old man handed him a sleek black credit card.
4,500 credits.
Arthur held it for a second. Just an hour ago, he couldn't afford a proper meal. Now, he could survive for months.
But money wasn't his goal.
"Show me your Necromancer skill books," Arthur said.
The old man barked a dry laugh.
"Necromancer? That trash class?"
He reached under the counter and tossed a worn, dark-purple book onto the table.
"This thing's been rotting here for three years."
Arthur placed his hand on it.
[Item: Skill Book - Summon Poison Skeleton]
[Tier: Common (Corrupted)]
[Effect: Summons a Level 1 Poison Skeleton]
[Warning: 90% chance of fatal backlash upon learning.]
"A suicide manual," the old man snorted. "Anyone who tried to learn it either died… or wished they had."
A corrupted skill. Fatal to anyone who used it.
Garbage.
For anyone else.
Arthur's heartbeat quickened.
A normal person would die instantly.
But Arthur wasn't normal.
His talent wasn't just fusion.
It was correction. Evolution. Perfection.
A flawed skill… could be fixed.
"I'll take it," Arthur said. "Deduct 500."
The old man stared at him like he was insane—but processed the payment anyway.
"Your funeral, kid."
Arthur ignored him.
He grabbed the book and stepped back into the neon-lit alley.
He didn't go home.
Instead, he slipped into an abandoned side street, checking his surroundings carefully.
No footsteps. No presence.
Good.
He raised his hand.
In his mind, his original skill appeared:
[Summon Skeleton Lv.1]
In his other hand—the corrupted book.
Arthur's eyes darkened.
"System…"
"Use Absolute Synthesis."
[Ding!]
[Target 1: Summon Skeleton (Lv.1)]
[Target 2: Summon Poison Skeleton (Corrupted)]
[Commencing Skill Synthesis…]
A violent surge of purple energy erupted from his hands, lighting up the alley like lightning.
The corrupted book trembled—resisting.
For a brief moment… the energy fought back.
Then—
It shattered.
The book disintegrated into particles of dark light, flooding into Arthur's body.
Power surged through his veins.
Cold. Sharp. Alive.
The system's voice rang out—clearer than ever before.
[Synthesis Successful!]
[Corruption has been completely purified.]
[Skill Mutation Complete.]
Arthur's breath slowed.
He opened his status panel.
His pupils shrank.
"…What the hell is this?"
A skill like this…
Should not exist at Level 3.