Everyone Else is A Returnee

Left behind on Earth while the rest of humanity is transported to other worlds to prepare for impending apocalyptic threats, Yu IlHan lives a solitary existence. Due to a bizarre anomaly—a divine oversight caused by a peerless cloaking technique that even the gods could not pierce—he was the only one omitted from the cosmic evacuation. For decades, he must endure a desolate daily life while waiting for the return of the human race. But when the rest of humanity finally comes back, they find that IlHan has spent his years of isolation honing his skills to absurd, god-like levels, setting the stage for an extraordinary journey of a uniquely overpowered protagonist.