The Crab with the Golden Claws: Part 2 - S1-E2
Other mistake: The newspaper article that features Tintin and Captain Haddock at the end of the episode is a flipped shot, as shown by the text that has been reversed. (00:43:35)
Continuity mistake: When Wizenheimer explains that he is an evil Koopa Wizard, Mario's black moustache turns brown. In the same shot, he and Luigi's grey shackles turn white like their gloves. (00:05:14)