Floating City - destiny is inviolable

From the future to the remote antiquity, from the beginning to the end, from the east to the west, a group of young people with missions embarked on a journey, just to find a common answer: where did we come from? Where are we going. Under the impact of a strong solar wind and magnetic storm, the earth's ecology has undergone drastic changes. Taking the Xuanyuan family’s descendants looking for the Xuanyuan Sword as the starting point of the story, it involves different story backgrounds and content in various historical periods of China, Europe, Australia, America and other continents (though all countries disappeared not only due to the solar wind, but because of the domaination of blockchian technology, and its decentralization). The eight nebula crystals are assembled to unlock the mystery and save the difficult journey of human destiny.