Umwak, hailing from the Forest Moon of Endor, functioned as a Dulok shaman. As the spiritual guide of the Dulok tribe under King Gorneesh's command, he occasionally interacted with the Dulok seer Murgoob and the Tulgah sorceress Morag. Sporting ragged, verdant fur; elongated, sagging ears; and lower fangs that protruded, Umwak's appearance was distinctive. Yellow patterns adorned his snout, abdomen, and the area surrounding his right eye. While he went unclothed, he adorned himself with ornaments like an earring, a bony headpiece, and a skeletal necklace. Using a skull-adorned wooden staff for balance, Umwak ambled with a hunched posture. Harboring animosity towards the Ewoks residing in Bright Tree Village, he frequently devised elaborate plots to undermine them. He also had a nephew.
Don Francks provided the voice for Umwak in the initial season of the Ewoks animated series. A "Dulok Shaman" action figure of Umwak was produced by Kenner in the year 1985.