In Chapterhouse Dune (1985), the Honored Matres have destroyed all of the Tleilaxu worlds in retaliation for the Tleilaxu role in programming the latest Duncan Idaho ghola with knowledge of how to sexually enslave Honored Matres. Scytale, likely the last surviving Tleilaxu Master, barely escapes the attack while leaving his homeworld and is given sanctuary by the Bene Gesserit. Essentially a prisoner, he is kept in a no-ship grounded on the secret Bene Gesserit planet Chapterhouse.
In exchange for their protection, Scytale has given the Bene Gesserit the knowledge to create axlotl tanks to grow their own gholas. Desiring his own Face Dancer servants, axlotl tanks, and access to the ship's systems, Scytale has held back the secret to creating artificial melange for future negotiations. His secret bargaining chip is a nullentropy capsule containing cells carefully and covertly collected by the Tleilaxu for millennia:
Scytale rubbed his breast, reminding himself of what was hidden there with such skill that not even a scar marked the place. Each Master had carried this resource — a nullentropy capsule preserving the seed cells of a multitude: fellow Masters of the central kehl, Face Dancers, technical specialists and others he knew would be attractive to the women of Shaitan ... and to many weakling powindah! Paul Atreides and his beloved Chani were there. (Oh what that had cost in searching garments of the dead for random cells!) The original Duncan Idaho was there with other Atreides minions — the Mentat Thufir Hawat, Gurney Halleck, the Fremen Naib Stilgar ... enough potential servants and slaves to people a Tleilaxu universe.
The prize of prizes in the nullentropy tube, the ones he longed to bring into existence, made him catch his breath when he thought of them. Perfect Face Dancers! Perfect mimics. Perfect recorders of a victim's persona. Capable of deceiving even the witches of the Bene Gesserit. Not even shere could prevent them from capturing the mind of another.
The tube he thought of as his ultimate bargaining power. No one must know of it.
Bene Gesserit leader Darwi Odrade notes that "Scytale admits to memories of Muad'Dib's times," and Herbert clarifies that Scytale is technically a clone, as the cells used to resurrect him had been taken from his living predecessor rather than a corpse. There is no indication in the text that this "reincarnated" Scytale possesses any of the Face Dancer abilities of his Dune Messiah incarnation.
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