The Stand-in - S1-E9
Revealing mistake: When Pufnstuf tries to reason with Witchiepoo, Witchiepoo hits him with a giant powder thing and shouts "Make up." When Pufnstuf falls over his head almost disconnects to his body.
H.R. Pufnstuf (1969)
1 mistake in The Stand-in - chronological order
Starring: Billie Hayes, Joan Gerber, Jack Wild, Lennie Weinrib
Witchiepoo: Stop eating your popcorn and be quiet.