Dimensional Alliance

For human beings, this is a world that is dying.
Since the European Observatory of the Roman Republic discovered in 4135 that an alien engineering ship began to build a Dyson sphere frame on the sun, human history has already entered the countdown to the end with half a foot.
Just when human beings gradually became desperate due to the gradual completion of the Dyson sphere, the prototype of the different world transition device finally started to operate in the underground high-energy physics research institute outside Suncheon City.
However, at the moment when the two worlds were connected through the transition device, a familiar yet unfamiliar clear-coded telegram was also transmitted from the other side of the device:
"Call, call, this is Wang Feng, Commander-in-Chief of the Great Wall Defense Line. There are a large number of Phase [-] defense lines in the north. The Miyun and Pinggu defense lines have fallen. Repeat, the Miyun and Pinggu defense lines..."