Igner

Igner is the dim, drooling son of Lrrr and Ndnd, rulers of Omicron Persei 8. He shuffles through scenes half-present, mouth open, seemingly incapable of following whatever crisis his parents are embroiled in, content to exist as a slack-jawed afterthought to intergalactic conquest.

John DiMaggio gives him a single perfect note—a low, wet, half-conscious mumble—and never breaks it, which is the joke. Igner works because the show refuses to explain him further; he's a running gag sustained entirely by commitment to blankness, a small dumb punctuation mark dropped into scenes of galactic menace.