Piratecat said:
(snip) I'd also consider having two suns in the sky at certain times of day, having the same effect.
Oh, I like that. I've had a few extra thoughts inspired by this suggestion from Piratecat.
Netherese wizards bear the stigma of having produced Karsus who used a powerful spell to steal the power of Mystra's predecessor which, as all FR fans know, resulted in the destruction of most enclaves and hastened the fall of the Netherese civilisation.
Netherese refugees established the nation of Halruaa and it wouldn't be inconceivable for one of more families to be related to Karsus. What if some scion of the family wanted to atone for this past misdeed of Karsus and thus has determined to resurrect, rather than slay, a deity and that deity is Amaunator?
If he succeeds, two suns appear in the sky, not concurrently but in some sort of succession so that there is no longer darkness or night. Can you imagine the consequences of this on food production, the effect on daily temperatures and melting icebergs, glaciers and snow?
Faerun would be hit by strife and chaos. Shar might even gain power despite the absence of darkness as people start praying for night to be restored. Cyric's religion would thrive amidst the chaos and potentially Bane's as well as the tyrant's faith provides a level of order and certainty that is otherwise lacking (I understand the Illuminati's motto is supposed to be "order out of chaos" which is what I'm getting at here).
Perhaps, too, the Halruaan mage responsible (high Int, low Wis and probably low Cha) is merely a pawn for the yuan-ti and their sarrukh masters who are using the Halruaan's research to perfect the ritual by which they will awaken Sseth or even Dendar the Night Serpent.
Anyway, all of this could make for an interesting Epic campaign.