Bene Gesserit
On Rakis, a girl called Sheeana (later revealed to be a descendant of Siona from the previous novel) has been discovered who can control the giant worms. The Bene Gesserit intends to use a Tleilaxu-provided Duncan Idaho ghola to gain control of this sandrider, and the religious forces of humanity who they know will ultimately worship her. The Tleilaxu have altered the ghola to bring its physical reflexes up to modern standards. The Bene Gesserit leader, Mother Superior Taraza, brings Miles Teg (also descended from Siona) to guard the new Idaho. Taraza also sends Reverend Mother Darwi Odrade to take command of the Bene Gesserit keep on Rakis. Odrade is a loose cannon; she does not obey normal Bene Gesserit prohibitions about love, and is also Teg's biological daughter. Bene Gesserit Imprinter Lucilla (yet another descendant of Siona's) is also sent by Taraza to bind Idaho's loyalty to the Sisterhood with her sexual talents. However, Lucilla must deal with Reverend Mother Schwangyu, head of the ghola project but also the leader of a faction within the Bene Gesserit who feel the gholas are a danger.