Continuity mistake: The blood Ashe smears on her face changes its pattern and consistency several times as the shots change. (00:36:00)
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.
The Origin of the Silver Surfer: Part 1 - S1-E1
Continuity mistake: When Shalla-Bal finds Norrin Radd unconscious after the temple cave-in, he is lying flat on the ground. When the shot changes, his head and shoulders are slightly elevated and resting against a piece of debris.