On the Rival Magic page I’ve just placed a picture, which is related to the Soqotran Sorcerers. Its presence though is deceptive: I only discovered it after the book was complete, and so the creature depicted, arguably, does not appear in the final book.
Indeed, if he did, I couldn’t show you his picture until the book was out. 8)
I personally think he looks magnificent. He’s meant to be lapis lazuli blue, by the way.