Apocalyptic notions that appeared in Shangqing Daoism were first developed fully by the Lingbao School. Lingbao cosmology supposed that time was divided into cosmic cycles, which correlated with the Five Phases. At the end of a cosmic era, the god of the colour associated with that era would descend onto earth and reveal a teaching that would save a fixed number of people from death. There were two types of cosmic eras, short ones that were characterized by an excess of "yin" energy, and long ones that were characterized by an excess of "yang" energy. At the end of a short cosmic era, the moon was prophesied to produce a flood that would erode the mountains, renew the "qi" of the universe, and change the rankings of the members of the celestial bureaucracy. At the end of a long cosmic era, evil creatures were unleashed, heaven and earth were turned upside down, and metals and stones melted together. The people who followed the correct teaching revealed by the god of the colour would be gathered up by the Queen Mother of the West and transported to a "land of bliss" that would not be affected by the apocalypse.