Lieutenant Arex, voiced by James Doohan, was a recurring character on Star Trek: The Animated Series which ran on NBC from 1973 to 1974.
Arex was a Starfleet officer assigned to the USS Enterprise as navigator. Arex was a member of a tripodal species (the Edosians) and had three arms and legs. Arex also sometimes took the conn, but he rarely left the ship on landing party missions.
For the custom I used the lower body of a Playmates Voyager Species 8472 figure and the upper body of a Playmates Trials and Tribble-ations Sisko. The extra arm came from a Kirk figure. I chopped off the hands and sculpted them, the head was sculpted from scratch. I used matte vinylic paint and bright vinylic varnish.