Guild Navigator - Prequels

Prequels

The Legends of Dune prequel trilogy (2002–2004) by Brian Herbert and Kevin J. Anderson establish that the Spacing Guild first start using Guild Navigators because the travel technique of spacefolding is not safe; only about nine out of every ten heighliners make it to their final destination without Navigators. Norma Cenva (the first Navigator and the creator of the Spacing Guild) at first uses super-computers to navigate space, but as the proscriptions of the Butlerian Jihad do not allow for the use of thinking machines, she uses melange to develop the prescient ability to visualize a heighliner's path before it actually travels. Cenva's own mutations are described at the end of The Battle of Corrin (2004):

Her direct physical senses were deadened, and Norma no longer cared about taste, touch, or smell ... She found it remarkable to see webbing between her fingers and toes. Her face, once blunt-featured and later flawlessly beautiful, now had a small mouth and tiny eyes surrounded by smooth folds. Her head was immense, while the rest of her body atrophied to a useless appendage.

In the Brian Herbert/Anderson Prelude to Dune prequel trilogy (1999–2001), some of the previously-unexplained process of becoming a Navigator is revealed through the story of D'murr Pilru.