"Global defence? It's really hard, and I can't even imagine it! " Chen Yang said.

Xuan Zhenghao said, "They can also break into zero and enter the earth separately. Therefore, it is not feasible to fortify part of the area, and it must be a complete and comprehensive distribution of defense.

Chen Yang said, "Can this be done?"

Xuan Zhenghao said, "Although it is difficult, we must do it. Moreover, at that time, we can be virtual and real, a small part of the virtual, most of the real.

Chen Yang said, "I understand what you mean. What do you mean by that?

Xuan Zhenghao said, "I explored in the...