Deliberate mistake: Hank only discovers the tattoo on the back of his head after having his hair shaved off. There is no way, however, he wouldn't have noticed it before this. The tattoo artist had to shave hair off the back of his head before putting on the tattoo. While he might have not realised right away, the pain the following day and the fact that he would have noticed a large part of his hair missing would make it unavoidable.
King of the Hill (1997)
1 deliberate mistake in season 7 - chronological order
Starring: Brittany Murphy, Pamela Adlon, Mike Judge, Kathy Najimy, Johnny Hardwick
It's Not Easy Being Green - S5-E16
Factual error: Boomhauer's car, Ms. Sally, has a Texas flag license plate on it. These plates were not issued until 1992, but Ms. Sally was driven into the quarry in the late 70's or early 80's.
Hank: Calm down, Boomhauer! I can't understand a word you're saying.
Trivia: One of the show's creators made a cartoon about a retarded pig. Boomhauer's voice is based on the voice of an angry viewer who called when he was offended by the cartoon.
Upvote valid corrections to help move entries into the corrections section.
Suggested correction: The person was actually complaining about "Beavis and Butthead." For some reason, they called the show "Porky's Butthole."
The Man Who Shot Kane Skretteberg - S2-E7
Question: When we first meet Kane Skretteberg, what is the song he and his band are playing in the garage? It is right before they start singing Funcenter over and over.
Answer: If you are talking about the "Thou shalt not do this, thou shalt not do that" song, I'm not sure if a song like that actually exists. Green Day, the guest voices on the episode, might have just been improvising to keep their appearance from being too obvious.