Have You Seen This Snail? - S4-E3
Other mistake: When Gary comes back at the end, when Gary meows and Spongebob says, "Yeah, like that," the tears in his eyes disappear for about half a second. (00:22:50)
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Enemy In-Law/Mermaidman and Barnacleboy VI: The Motion Picture - S4-E7
Other mistake: Plankton's phone doesn't have a 0 button on it.
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Bummer Vacation/Wigstruck - S4-E14
Other mistake: Bummer Vacation: When Spongebob says, "You're right, Gary. It is unhealthy to think of the Krusty Krab while I'm on vacation," his legs are missing. (00:05:55)