As the Avatars of Light and Dark pass so their former disciples assume the roles of Elder Gods. And just what did happen to Shadow?
In the fledgling universe the battle between Good and Evil has already begun.
Read: Birth Of A Conflict
With the ending over the next story can begin. Sometimes multiple times.
Read: Birth and Rebirth
Before something new can begin, the old must make way. Behold the end of the universe.