Dave Flusher III appears in the episode A Mine is a Terrible Thing to Waste Part I and A Mine is a Terrible Thing to Waste Part II. He answers Sludge's ad for "A heinous henchman to serve a machiavellian master." Flusher admits he doesn't know what it means, but he says he's the man for the job.
He is tall and muscular, with a deep voice. He has blonde hair and has a gold front tooth. Flusher is obviously stupid, which suits Sludge fine, as Flusher obeys orders easily.