Pangu can be interpreted as another creator deity. In the beginning there was nothing in the universe except a formless chaos. However this chaos began to coalesce into a cosmic egg for eighteen thousand years. Within it, the perfectly opposed principles of yin and yang became balanced and Pangu emerged (or woke up) from the egg. Pangu is usually depicted as a primitive, hairy giant with horns on his head (like the Greek Pan) and clad in furs. Pangu set about the task of creating the world: he separated Yin from Yang with a swing of his giant axe, creating the Earth (murky "Yin") and the Sky (clear "Yang"). To keep them separated, Pangu stood between them and pushed up the Sky. This task took eighteen thousand years, with each day the sky grew ten feet higher, the Earth ten feet wider, and Pangu ten feet taller. In some versions of the story, Pangu is aided in this task by the four most prominent beasts, namely the Turtle, the Qilin, the Phoenix, and the Dragon.