Picking up a Sword from a Street Stall, I Awakened the Sword Master's Legacy

Have you ever thought that beneath the steel and concrete of the urban jungle lurk ancient evil spirits that yearn to devour people? Monsters, ghosts and monsters are eroding the human world. Under the splendid city, there are unknown horrors hidden. A huge creature flew up from the depths of the ocean, setting off a world-destroying tsunami. Someone needs to put an end to all this. "If the dark night falls." "I, the human swordsman Xu Yun, only have one sword!" "This sword can protect the human race from worries." "This sword can kill weird and evil things." "Those who wish to save the building from falling should stand up!"