I Became a Legend After My 10 Year-Long Last Stand.

During an expedition, the Hero's company is overwhelmed by a horde of devils. Luck, the most powerful wizard, decides to face them alone to save his companions. From that moment on, he fights continuously for ten years, finally exterminating his enemies and returning victorious. Upon his return, he discovers that his name is now legendary, celebrated with statues and coins, while his body, rejuvenated by the energy he has absorbed, belies the age and experience of a veteran. To avoid attracting attention, he chooses to hide his identity and set out again as a simple, low-ranking adventurer, in a world that seems peaceful... but is not.