Hundreds of years ago, the entire world changed due to unknown reasons, and the end began. Gradually, people could not even survive on the land, and could only hide underground, just to live.
Hundreds of years later, the original land has been completely deserted by yellow sand, and the world has completely given up on the original human beings. However, the remaining people are still living a difficult life relying on their tenacious adaptability.
The emergence of new humans seems to be in line with the birth of the world.
