I am trying to find the name of a fantasy film from the late 70s or early 80s. There was a hero, and there was an elf, and a villain who had a metal helmet with a patch over it that covered one eye. At the end of the film the helmet comes off to reveal the eye is burnt or scarred or missing (cant remember exactly which). I think that also at the end of the film it is revealed that the hero and the villain are related (brothers I think). I cannot remember any other details. Does anyone know the name of this film?