How does a monarch lose the mandate of heaven and what are the consequences of this loss?

When the Mandate of Heaven is lost (mostly in China), the gods no longer believe that that monarch, emperor, or dynasty deserves to have control over an empire. This can be caused by failure to stabilize the economy or social system, or some other embarassing event.

When the Mandate is lost, the empire usually falls apart and enters a state of civil war, where several camps battle for control over a new empire, and thus, a new dynasty.