Night Bringer and Bright Justice quarreled between them and their regions took the brunt of their fight. Ice/snow/rain coated their regions for ~26 days and nights. Darkness snuffed out the light tipped mountains for half of that time and it became known as the Cold Slumber to many afterward. No such event between the siblings has taken place since then and no one, mortal at least, is aware of how it started or ended. ~329 T.S.