Three Phases Without Self

Who made the Tai Chi diagram that cannot be refined? What is beyond Middle-earth? Why is there such a catastrophe in the world of immortality? What's the secret of the pillar supporting the sky at the center of the world? What do the four invincible people who have emerged in the 900,000-year history of immortality hide? Why did Penglai and Kunlun become forbidden areas for mortals? Where does the heavenly palace that occasionally appears on the horizon come from? It all seems to start with a variable that shouldn't exist...