From their first film, Phallus In Wonderland, Gor Gor by Gwar.
This movie was so over the top gory, cartoonish and offensive, I kept the VHS hidden for years, because I knew how much trouble I'd be in for bringing something like Gwar into the house. Hell, Alice Cooper and Iron Maiden were BANNED in my house! Amusingly, I could actually watch the most violent Stallone and Ah-nold films, but there better not be so much as a nipple any where! Much less giant mutant dongs, geez!
Just for fun, here's Gwar on Joan Rivers' Show
And on Alex Winter's The Idiot Box (MTV's best show ever..?)