He was co-credited with the series theme song as "Erika Lane". This pseudonym came from his two children, Erika Lane and had also been used as a character name on the 1967 Filmation series Journey to the Center of the Earth.
As "Erik Gunden", Scheimer did the voice acting for such characters as Orko, King Randor, Stratos, Trap-Jaw, and many others. The last name was taken from his father's original surname: "Gundenscheimer" (which was later shortened to Sheimer). The first name was Lou's middle name, which he was not given by his parents, but instead by his wife Jay, who felt that he should have one.
While most of the voice actors recorded their lines together as an ensemble, Lou felt he wasn't good enough to perform together with trained actors, so he always recorded his lines by himself, after hours. The pitch of his voice was often changed by using a "harmonizer" which could control the pitch without altering the speed of the sound.
The reason producer Lou Scheimer performed the voices for so many supporting characters on He-Man and the Masters of the Universe and She-Ra: Princess of Power was that the "official" voice actors were contracted to perform no more than three different voices per episode. And since there were usually only three regular cast members working on each show, Lou would fill in the rest of the male cast. This is also why his wife Jay and daughter Erika did various small parts in the first season of He-Man. During the second season of He-Man and all of She-Ra, Erika Scheimer received an on screen credit as an actor and also directed the voice actors, and she and her father would record the remaining voices on their own later.