The Voyage of the Stars and the Sea

An inexplicable virus infected and killed 4/5 of the world's human population. In order to avoid the virus infection, the remaining humans immigrated to the Sky City space station. 150 Years later, the humans in Sky City returned to the earth, but were forced to start a war with the mutated creatures on the earth... In the end, humans won, but the earth was no longer suitable for human life. Humans have chosen to leave the solar system and look for planets more suitable for human habitation...