Worldchanging

In a peaceful and technologically advanced world, humans stand at the pinnacle of all beings as ruthless dictators. When a worldchanging event happens, the once forgotten original look of the world is suddenly restored. The six realms, once lost to history, has now appeared before the eyes of mankind once more with humans, deities, demons, devils, ghosts, and gods all co-existing in this absolute madness of a world. In the face of such strong adversary, what will the weak humans do to survive?