(Journey through the Multiverse) How strong can I become*

For seventeen years, Kim Joon lived by one simple principle: prepare for the worst. While the world ignored scientists' warnings, he turned his family's rural home into a fortress. He dug, stocked, and fortified, creating a perfect bunker to survive the coming collapse. He was ready for war, famine, even nuclear fire. He saved his mother and locked the thick steel door behind them, just as the world ended in a symphony of mushroom clouds.

But he wasn't ready for this.

When the Geiger counters finally fall silent and the food supplies run critically low, a strange, shimmering rift tears through the reinforced concrete wall of his sanctuary. It's not radiation sickness. It's a gateway.

On the other side lies not the scorched wasteland of his Korea, but a vibrant, untouched city under a blue sky—a world where the war never happened. A world with food, water, and life. A world with its own, very much alive, Kim Joon, who chose a career in the city over his parents' farm.

Now, the survivor from a dead timeline must face his greatest challenge: not radioactive mutants or desperate scavengers, but his own mirror image and a society that sees him as a dangerous relic of a catastrophe they avoided. How far will he go to secure a future in a world that already has a version of him? And what secrets does this peaceful timeline hold about the cause of his own world's destruction?