Keith's Machinations, Part 2 - S1-E32
Other mistake: When Baby Dragon evolves into Thousand Dragon, the monster's defence points are 2500. However, Thousand Dragon only has 2000 defence points. (00:06:30)
Yu-Gi-Oh! (1998)
1 other mistake in Keith's Machinations, Part 2 - chronological order
Starring: Eric Stuart, Amy Birnbaum, Dan Green, Darren Dunstan
Genres: Action, Adventure, Animated, Family, Fantasy, Thriller
Duel Identity, Part II - S1-E30
Character mistake: Yugi mistakenly says if he doesn't get a monster out to defend himself Mai can attack him directly, which wouldn't be possible since the rules of Duel Monsters during the Duelist Kingdom arc forbade direct attacks on defenseless opponents. That rule wouldn't be implemented until the Battle City arc.
Seto Kaiba: I'm surrounded by superstitious nitwits.