Doomsday Me Obtain the Inheritance of Yang Jian?

When the monsters in "The Classic of Mountains and Seas" appear in reality, when the lost ancient era revives again, and in a new era where monsters are rampant, where should the human race go? The era changes, the doomsday comes, and four giant cities descend in the void. Each giant city is a small world. The human race hides in the giant city to recuperate, and outside the giant city, the guardians are staging a fight between spiritual beasts and spiritual practitioners... Thousand-meter-high mountains, foggy swamps, boundless oceans, etc. Have appeared in the world one after another. The earth has returned to its original appearance, and its territory has expanded infinitely... However, mysterious ruins also began to appear, and ancient secrets were gradually unveiled...