Blue Age

The Blue Age was a time in the ancient history of Abeir-Toril when life on the planet resided in a single, vast ocean. The war between the gods and the primordials raged mostly over this unfortunate planet at the time and one of the primordials, Dendar the Night Serpent devoured one of Selûne's most favoured creations, the sun (a feat her sister Shar had been attempting since it's creation). The temperatures on Abeir-Toril subsequently dropped markedly and not long afterwards, most life on the planet became extinct. Thus ended the Blue Age and gave rise to the Shadow Epoch.