Orrimaarko was a Dressellian male who fought for the Alliance to Restore the Republic during the Galactic Civil War. He opposed the Galactic Empire. He was present at a planning session aboard the MC80 Star Cruiser Home One not long before the Battle of Endor. This battle saw the Alliance launch an assault on the Empire's DS-2 Death Star II Mobile Battle Station superweapon positioned above Endor's moon. Orrimaarko later joined the Endor strike team under the command of General Han Solo, traveling to the Forest Moon of Endor on the stolen Lambda-class T-4a shuttle named Tydirium. His skin was a light brown color, and he had black eyes, though one of them was covered with an eye patch.
Star Wars: Episode VI Return of the Jedi marked Orrimaarko's debut. The character was initially known only as "Prune Face," a name given to his 1984 action figure. Pablo Hidalgo later officially named him Orrimaarko in Galaxy Guide 12: Aliens — Enemies and Allies, a Star Wars Legends sourcebook published by West End Games in 1995.
The 2018 reference book Star Wars: Alien Archive identifies Orrimaarko as a member of the Endor strike team during the Battle of Endor; this is supported by his appearance aboard the Tydirium behind Han Solo as he entered the cockpit. However, in the 2019 novel Resistance Reborn, Orrimaarko tells Leia Organa that he wasn't on the ground during the battle.