An explanation of Face Dancers and their Bene Tleilax makers in "Dune: Prophecy"

'Dune: Prophecy:' What are Face Dancers and who are the Bene Tleilax?

Source: space
Source Link: https://www.space.com/entertainment/dune-prophecy-what-are-face-dancers-and-who-are-the-bene-tleilax