H.R. Giger, the famous creator of the Xenomorph in the science fiction classic ALIEN, was also part of the all star team that worked on Jodo's Dune. The enclosed design of the castle fits perfectly with the description of Harko City in the books, which is probably just a happy coincidence. The elongated back of the head is an obvious resemblance to the aforementioned Xenomorph.
Das erste Buch ist ausreichend, mehr geht immer wenn du dann möchtest :)