This is a future era. Before the Third World War in the 21st century, it was called modern times. After the end of World War IV, it was defined as modern times. Only after breakthroughs in physics are modern times.The era when civilizations, countries, and societies began to invest in power to interfere with time, space, and planes.The main world, the earth, is the only real world in all time and space. After opening the crystal wall with technology, the mad dogs on the earth began to watch the Yuan Dynasty