Ao

Lord Ao was an Overgod in the Forgotten Realms Universe. Also known as the One Who Is Hidden, he was credited with creating the cosmos and all the gods, and brought order out of chaos, so that worlds could exist.

In some traditions, Ao just created the sphere that covered Realmspace (one of the realms in the material plane), and the goddesses Selûne and Shar, and they later went to create all the worlds and stars, and other heavenly bodies. In other accounts, it was Ao who directly created all that exists, not only Realmspace, but also the worlds and heavenly bodies. Ao himself claimed to be the creator of the gods, though not of the Realms themselves (which may have been attributed to Io).