The Creepy Creature of Vulture's Claw - S3-E10
Deliberate mistake: Professor Greer's fleeing from the room one moment, then suddenly he's behind the gang dressed up as the Mantis.
The Scooby Doo Show (1976)
1 deliberate mistake in season 3
Starring: Frank Welker, Don Messick, Casey Kasem, John Stephenson
Continuity mistake: In the episode of Scooby movies where they meet the Three Stooges, Fred says that Velma is missing and they need to find her. When they go off to look for her they pass a window. Fred first, Daphne, then Velma (despite her being the one missing!), Shaggy, then Scooby.
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