Chapterhouse: Dune

The Bene Gesserit, often called The Sisterhood, is an ancient, all-female organization. They operated in a way that is mysterious and impenetrable to outsiders. Their ranks consist of spies, scientists, and political advisors that insinuate themselves into all levels of all factions. They use political, personal, and religious manipulation to further their aims. They often create and preserve breeding programs for important traits among mankind.

Sisters of the Bene Gesserit have many abilities. These include internal organic-chemical control, which allows them to consciously alter their body chemistry. The Voice, an ability to influence and command people by speaking in a certain pitch, is impossible to disobey for most humans. They also possess Fertility Control, which gives them the ability to control their menstrual cycle and choose the gender of their child at the point of conception.

The Bene Tleilax, also called the Tleilaxu, were a faction of genetic engineers. They were frowned upon by many other factions in the Old Imperium, yet their services were widely sought. They created the Face Dancers and gholas, and thanks to their axolotl tanks, they were a major source of Spice Melange. The Honored Matres destroyed them, leaving only a single survivor, Scytale, who resides in Bene Gesserit custody.