Hailing from the forest moon Endor situated in the Outer Rim Territories, Duloks were a sentient species that thrived in swamps. These aggressive, lanky bipeds had four-fingered hands at the ends of their upper limbs. Notable features included their long, drooping ears and a mouth filled with teeth, including two prominent teeth on the upper jaw that were visible when the mouth was closed. They emerged from the swamps to hunt lantern birds as well as the sentient Ewok species, with whom they shared the moon and competed for the same resources. Imara Vex, a human, once described the relationship between Ewoks and Duloks as one of "natural enemies" due to this rivalry.
One group of Duloks were known as the Children of Vulgarr, who were under the leadership of King Gorneesh. A religious leader was also among their members. During the New Republic Era, Gorneesh and his followers made an attempt to seize control of the Ewok Bright Tree Village, which triggered the Ewok Civil War.
The Duloks were originally conceived for The Adventures of Teebo: A Tale of Magic and Suspense, a Star Wars Legends book for children that was both written and illustrated by Joe Johnston and published in 1984. Furthermore, they played significant roles as antagonists in the animated television series Ewoks, which also belonged to the Legends continuity. The species' place in canon was verified in 2014 through the Star Wars Workbook: 2nd Grade Reading.