Technology Saves the World

Three years later, the world changed. Various alien creatures and civilizations came to the earth one after another, and wars broke out. Human beings, on the other hand, can only survive in it with difficulty and eventually perish miserably. The protagonist, Gu Bai, was reborn three years ago with the technological civilization system, before everything happened. Let's see how he uses the system in his hands to open up a scientific and technological avenue for mankind this time, leading mankind to counterattack alien creatures.