From Muppet Wiki

The Mystics are a race of characters from the Creature Shop film The Dark Crystal.

At the last Great Conjunction, the urSkeks were divided into two races - Mystics and Skeksis. The four-armed Mystics (also called urRu) took on the sorrows of the world. They inherited the mystical wisdom of the urSkeks, but were powerless to use it outside their own valley. Their hopes for redemption rested on Jen. There were originally 18 Mystics, but by the time of the Great Conjunction when they rejoined the Skeksis, only 8 remained.

Mystics

• urAc the Scribe
• urAmaj the cook
• urIm the Healer
• urNol the Herbalist
• urSen the Monk
• urSol the Chanter
• urSu the Master
• urTih the Alchemist
• urUtt the Weaver
• urYod the Numerologist
• urZah the Ritual Guardian

Puppet Operation

The Mystic puppets are full body puppets, which are mainly operated by mimes and dancers. The operators have to crouch down on their haunches, with one arm stretched out in front to operate the jaw, while the other arm operates one of the puppets' front arms. Fine facial movements, such as blinking or moving eyes, were operated by another puppeteer by remote control.