From the Discworld books by Terry Pratchett

Blind Io is foremost of all the gods on the Disc. He has no eyes in his head, but many that circle around him, almost with an intelligence of their own. One was unfortunately consumed by a raven. Anyway, due to this he said to be able to see everywhere, and it is for this reason he is the chief of the gods.

His primary godly role is that of thunder god. While there are over seventy "different" thunder gods on the Disc, he appears to the faithful while using an assortment of false noses, and hammers so . His origins are shadowy, and he is thought to have come to the Disc in some form of cosmic accident.