Ao

Ao is the Overgod of the Forgotten Realms Crystal Sphere of the Dungeons & Dragons multiverse. As Overgod, he is, essentially, the God of Gods, the aloof and indifferent ruler over all deities who occasionally bestirs himself to smack them all upside the head when they do something he finds unforgiveably stupid. The most major event of that was the Time of Troubles, when he expelled all of the gods bar Helm from the heavens over Bane and Bhaal stealing the Tablets of Fate. This was ultimately revealed to actually be an excuse and really he was just sick of how the gods were so indifferent to their followers' plights. When he did end the Time and let them back in, it was only after changing things so that their power levels now depended on the faith of mortals; if a god lost all of its followers, it would fade away into nothing, whilst the more followers that god had, the mightier it would grow. This did make the gods more attentive of their followers, but it also led to much more aggressive proselytizing, too.

Those few eccentric mortals who learn of Ao sometimes seek to worship him; this is a foolish decision, as Ao's Overgod status means he is exempt from the "gods need prayer badly!" trope and also has far bigger things to concern himself with than mortals. As a result, such "priests" gain no spells and will never even attract Ao's notice, for they are simply too far beneath him to care.

Not to be confused with Io, who is the Overgod of the Dragon deities.