[Michael Cule]

I was assuming it was there to cover the Sahudese spirit magicians.

Who are definitely mentioned as existing and strongly implied to have real power so if and when MAGICAL STYLES: YRTH ever comes out they're going to have to be covered. (Dr Kromm, take note!)

(Me I don't worry so much and mix and match just about everything in my version of Yrth, including secret psionic conspiracies working with the Underground Engineers and a Cabal Flying Saucer base on the Moon.)