Hang in There, Scooby-Doo - S2-E3
Continuity mistake: The pile of bootleg records suddenly gets bigger after Velma's shown holding some of them.
The Ghost of The Bad Humor Man - S1-E4
Continuity mistake: The back doors of the armored truck that the phantoms are trapped in go from being open to closed to open again.
A Frightened Hound Meets Demons Underground - S1-E14
Character mistake: Velma mentions Seattle burned down in 1890. The fire went from June 6-June 7 1889.
The Creepy Heap from the Deep - S2-E8
Audio problem: When speaking about the hidden beauty parlor in the submarine Velma's voice comes from Daphne's mouth briefly.
The Creepy Heap from the Deep - S2-E8
Continuity mistake: Captain Clement's hair and beard briefly go back to his natural grey when he's still in his zombie makeup during the submarine chase.
The Chiller Diller Movie Theater - S2-E4
Continuity mistake: Scooby Dum's collar goes from its usual red to yellow briefly in one shot on the train.
Scooby's Chinese Fortune Kooky Caper - S3-E12
Continuity mistake: When Shaggy and Scooby start changing the Mystery Machine's back right tire, it's flat. When the Moon Monster shows up it's fixed, and they've just started jacking it up.
The Harum-Scarum Sanitarium - S1-E11
Continuity mistake: Fred and Velma get chased by one of the dogs into the room where Shaggy and Scooby are. Daphne wasn't with either pair, yet she's suddenly there once Fred closes the door.
Scared a Lot in Camelot - S1-E10
Other mistake: Fred calls out to the Black Knight ghost who sees and hears him. Yet it's Shaggy and Scooby in different armor who enter the room.
The Chiller Diller Movie Theater - S2-E4
Plot hole: Given Jim Moss, the studio chief, is already on the train, it makes no sense for him to have been in the coffin. That and how he managed to slip into it without being seen by the conductor or anyone else.
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 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 Creepy Creature of Vulture's Claw - S3-E10
Plot hole: It's not explained how Professor Greer, a man of medium height, say five feet seven inches tall, could make himself look like he's seven feet. Maybe stilts but those would surely protrude out.
The Ozark Witch Switch - S2-E6
Plot hole: It's never explained how any of the Hatfields could've left a pile of sawdust at their cabin.
Plot hole: Given it's a government building there's no way the ghosts could drill into the U. S. Mint and not draw security's attention.
