The Creepy Creature of Vulture's Claw - S3-E10
Other mistake: The whole time Professor Greer's the Mantis he's around seven feet tall. When he's unmasked he's suddenly his own size again.
The Scooby Doo Show (1976)
1 other mistake in season 3 - chronological order
Starring: Frank Welker, Don Messick, Casey Kasem, John Stephenson
Vampire Bats and Scaredy Cats - S2-E2
Continuity mistake: When Lisa's uncle shows her her grand-father's picture, it changes from one shot to another.
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