Character mistake: On Rebecca's first turn, she summons a monster which she refers to as Luster Dragon #2. The monster she actually summons is called Luster Dragon. Luster Dragon #2 is a Level 6 monster with 2400 attack points (which she couldn't have summoned without a sacrifice) and has a turquoise design, whereas Luster Dragon is a Level 4 monster with 1900 attack points and has a blue design (which is the monster that is summoned to the field). She doesn't summon Luster Dragon #2 until later in the duel. (00:11:14)
Flight of Fear: Part 1 - S4-E22
Character mistake: Kaiba uses the special effect of XYZ-Dragon Cannon, which he states that "by discarding one card, he can destroy one of Alister's cards," but he is shown sending three cards from his hand to the graveyard instead of one. Activating this effect does destroy all three of Alister's Tank Tokens, so the correct number of cards is destroyed, despite stating the wrong number of cards. (00:17:20)
Flight of Fear: Part 2 - S4-E23
Character mistake: When Alister activates Toy Robot Box, he says that by discarding three cards from his hand, he can summon three more robots. However, he is only shown discarding one card from his hand. (00:11:40)
A Duel with Dartz: Part 2 - S4-E34
Character mistake: When Kaiba summons Blade Knight, he says, "Since I only have one card left in my hand, Blade Knight gets another 400 attack points." However, Kaiba has no other cards in his hand. Blade Knight was the last card in his hand before he summoned it. (00:14:00)
A Duel with Dartz: Part 2 - S4-E34
Character mistake: When Kaiba activates the Ring of Destruction trap card, he says, "Your knights are only safe if your Mirror Knight Calling magic card is in play," to Dartz. However, the Mirror Knight Calling card was shaded blue when it was summoned, meaning it is a Ritual Monster and not a spell/magic card. (00:19:23)
