Blue Star Is Only a First-Level Civilization, Why Can Everyone Fly?

[Technology + Immortal Cultivation + Aliens + "Friendly Exchanges" between Countries + Ancient Civilization] It turns out that Blue Star has been in contact with alien civilization for thousands of years. Suddenly one day, an unknown electrical pulse signal sounded at the Zhongxia Space Research Institute. In response, everyone at the institute immediately reported the news. At the same time. Zhongxia Kingdom, on a high building in Pengcheng. A man in black robe counted with his fingers, his face became serious, and he said to himself secretly. "The end is coming." Five hundred years later. The alien civilization came as expected and invaded the earth. Once they entered, they were stunned. "How did they fly?" "No cab, no flamethrower, nothing, just a flying sword!" The Blue Star people also noticed them and showed a jeering laugh, "You are finally here, I have been waiting for you for a long time!" The alien civilization screamed in panic, "Run quickly, are these Blue Star people not human?"