The Demon King's throne room stank of sulfur and death.
Kang Minho stood alone amid the corpse of what was once humanity's greatest strike force. Twelve SSS-Rank hunters had entered the Final Dungeon. Now only one remained standing.
Blood dripped from his shattered sword—what was left of Heavenly Dragon's Fang, the blade that had slain a thousand dungeon bosses. His armor, forged from the scales of an Ancient Wyrm, hung in tatters. Three ribs were broken. His left arm wouldn't move properly.
But he was still standing.
The Demon King, or what remained of him, wasn't.
"Is this... victory?" Minho's voice echoed in the vast chamber.
Around him lay the bodies of legends. Park Jin-seok, the Flame Emperor. Lee Soo-jin, the Void Walker. Kim Tae-young, his best friend since the First Cataclysm, the man who'd saved his life seventeen times.
All dead.
Minho limped toward the throne, each step sending waves of agony through his body. The System notification he'd been ignoring finally forced itself into his vision:
**[FINAL DUNGEON CLEARED]**
**[Humanity Saved]**
**[Title Acquired: Dragon Slayer]**
**[Level Up!]**
**[Level Up!]**
**[Level Up!]**
**[You have reached Level 389]**
He dismissed them all with a thought. What good were levels when everyone he cared about was gone?
The massive obsidian doors at the chamber's far end began to glow. The exit. Freedom. The outside world where humanity would be celebrating their salvation, completely unaware of the price paid for it.
Minho took one last look at his fallen comrades. "I'll make sure they remember you all. I promise."
He turned toward the exit—
**[SYSTEM ALERT]**
**[ERROR]**
**[ADMINISTRATOR OVERRIDE DETECTED]**
Minho froze. In twenty years of hunting, he'd never seen a message like this.
The air in front of him rippled, and a window appeared. Not the familiar blue of the Hunter System, but a deep crimson that made his instincts scream danger.
**[CONGRATULATIONS, KANG MINHO]**
**[You have been selected]**
"Selected? Selected for what?" His hand moved instinctively to his broken sword.
**[The First Cataclysm was merely a test]**
**[The real invasion begins in 10 years]**
**[Current humanity survival rate: 0.003%]**
The words hit harder than any demon's attack.
"What... what are you talking about? We just saved humanity!"
**[You saved them from the tutorial]**
**[The Demon King you defeated was Rank 47 out of 72 Demon Lords]**
**[He was the weakest]**
Minho's legs gave out. He collapsed to his knees, staring at the message in horror.
"That's impossible. We sacrificed everything—"
**[Your sacrifice was admirable]**
**[That is why you have been chosen]**
**[HIDDEN CLASS UNLOCKED: THE LAST GUARDIAN]**
A new window exploded into existence, filling his vision with text:
**[CLASS: THE LAST GUARDIAN]**
**[MISSION: Prepare humanity for the Second Cataclysm]**
**[TIME LIMIT: 10 years]**
**[SUCCESS REWARD: Humanity survives]**
**[FAILURE PENALTY: Complete extinction]**
**[RESTRICTIONS:]**
**- You cannot reveal your identity as Kang Minho**
**- You cannot use your fame or authority**
**- You cannot directly command or lead**
**- You must train the next generation in secret**
**[QUESTION: Do you accept this mission?]**
**[YES / NO]**
Minho stared at the options. His body was broken. His friends were dead. He was so tired.
But the alternative was watching humanity die knowing he could have done something.
"If I refuse?"
**[The timeline continues as normal]**
**[In 10 years, 72 Demon Lords invade simultaneously]**
**[Humanity is extinct within 3 months]**
**[You will remember this conversation]**
So it wasn't really a choice at all.
Minho thought of all the people outside the dungeon. The children who'd been born into a world with dungeons and monsters. The families of his fallen comrades. The hunters who looked up to him as humanity's strongest.
They all deserved a chance. Even if he couldn't give them certainty, he could give them preparation.
"What happens if I say yes?"
**[Your 'death' will be arranged]**
**[You will be given a new identity]**
**[Your level and stats will be sealed]**
**[You will have 10 years to prepare humanity's next generation]**
**[The method is up to you]**
"Sealed? How am I supposed to train anyone if I can't use my abilities?"
**[Your knowledge remains]**
**[Your experience remains]**
**[Your techniques remain]**
**[Power can be borrowed, but wisdom must be earned]**
**[Will you save them again, Kang Minho?]**
He closed his eyes. Thought of Kim Tae-young's last words as he lay dying: "Make sure they remember us, Minho. Make sure it meant something."
This was how he'd make it mean something.
Minho reached out and selected YES.
The world exploded in crimson light.
---
**[HIDDEN CLASS: THE LAST GUARDIAN - ACTIVATED]**
**[Beginning regression sequence]**
**[Timeline shift: -20 years]**
**[Memory retention: 100%]**
**[Identity erasure commencing]**
**[Good luck, Guardian]**
The last thing Kang Minho, humanity's strongest hunter, saw before his consciousness faded was the smiling faces of his fallen comrades.
"I won't let you down," he whispered. "Not this time."
---
**[SYSTEM NOTIFICATION - GLOBAL]**
**[BREAKING NEWS: SSS-RANK HUNTER KANG MINHO KILLED IN DUNGEON COLLAPSE]**
**[The Dragon Slayer, age 45, died securing humanity's future]**
**[He died a hero]**
**[Status: DECEASED]**
---
But in a small apartment in Seoul, a man with no identification, no history, and no name woke up gasping for air.
He looked at his hands. Younger. Unmarked by scars.
The System window appeared:
**[Welcome back, Guardian]**
**[Current Date: March 15, 2045]**
**[Time until Second Cataclysm: 3,652 days]**
**[Your new identity has been prepared]**
**[Name: Kim Soo-hyun]**
**[Age: 37]**
**[Occupation: ...]**
Minho—no, Kim Soo-hyun now—held his breath as the last line appeared.
**[Occupation: Janitor - Seoul Hunter Academy]**
He stared at the words for a long moment. Then, despite everything, he started to laugh.
Twenty years as humanity's strongest hunter. Five years as an SSS-Rank legend. And now?
Now he was going to change the future armed with a mop and bucket.
"Well," he muttered, standing up and stretching his new-old body, "at least no one will expect this."
The System chimed one last time:
**[Report to Seoul Hunter Academy tomorrow, 6:00 AM]**
**[Your real work begins now]**
**[Don't be late, Janitor Kim]**
Kim Soo-hyun smiled grimly. In ten years, the real demons would come.
But first, he had students to train.
Students who didn't even know they needed training yet.