If a shaman-elect, on the day of his succession to office, successfully powders up and inserts into various orifices the mystic mushroom, partakes of the sacred toadstool, smokes sufficent of the holy rhizome, then whilst sitting crosslegged under a pine tree is not distracted by blue four-sided triangles pin-wheeling across his visual field, and can prevent the top of his head from unscrewing and drifting away, he may then see the god Topaxci. This earns him the title of "Shaman". Other gods that may be seen include Skelde, Spirit of the Smoke and Umcherrel, the Soul of the Forest. Seeing either of these will entitle the shaman to a different title.
The god is also known as Topaxi the god of certain mushrooms, and of "great ideas that you forgot to write down and will never remember again", and some other things. He is featured in a painting by Paul Kidby as published in The Last Hero.
Mentioned in The Light Fantastic.