Continuity mistake: When Banner tells the trio that shadow duels are duels played with powerful mystical items, Jaden's hands are on the table, but when the shot cuts, Jaden suddenly has his right hand on his chin. (00:04:25)
Continuity mistake: After Banner mentions the powerful mystical items, Jaden replies "Millennium items, right. I've heard about this, but it's not true" and is smiling when he says this. In the next shot, he suddenly isn't smiling. (00:04:29)
Continuity mistake: When Jaden asks Alexis why she is at the abandoned dorm, Alexis replies, "I have my reasons that's why" and raises her right hand to her chest. In the next shot, her right hand is suddenly lowered. (00:08:42)
Continuity mistake: When Chumley hands Jaden his duel disk, Jaden puts it on and his deck of cards cannot be seen inside it. Jaden then walks over to face the Shadow Duelist, where his deck is suddenly inside the duel disk. Then a few seconds after that, he puts the deck of cards in the duel disk. (00:12:13)
Revealing mistake: When the duel begins, the Shadow Duelist goes first. He has five cards in his left hand and draws a sixth card from his deck. He then places the sixth card next to the fifth card, and then picks up the fifth card in his hand, but the sixth card remains in the same position, without its position being affected by the fifth card being picked up. (00:12:32)
Revealing mistake: After the Shadow Duelist summons Infernal Queen Archfiend, Jaden says, "An Archfiend monster?" and the shot cuts back to the Shadow Duelist saying with that card on the field, every monster with Archfiend in its name gain 1000 attack points. In this shot, take note of the cards he is holding in his hand. He only appears to be holding onto two of the cards, but every other card in his hand appears to be held perfectly fine despite him not holding onto them. (00:12:41)
Continuity mistake: When Jaden tells the Shadow Duelist to leave his friends out of this, he draws a card with his right hand. When he does this, his left hand is lowered, but when it cuts to a close-up of the cards in his hand, his left hand is suddenly raised to be level with his right hand. (00:14:00)
Character mistake: The Shadow Duelist activates the effect of Terrorking Archfiend, where he states if the monster is targeted by an opponent's card, a number between 1 and 6 is chosen at random, and if the number selected is 2 or 5, then Terrorking Archfiend won't be affected by it. Chumley then states the odds are in Jaden's favour, to which Syrus dismisses this, saying he flunked math. However, Chumley is actually correct, as the odds for Jaden are 4 in 6, whereas the odds for the duelist are 2 in 6. (00:15:45 - 00:16:09)
Revealing mistake: After the Shadow Duelist has activated the effect of Terrorking Archfiend and the flame has landed on the ball labelled 2, just as he says, "Mirror Gate is shattered", the card shown on his duel disk is misshapen, where two corners of the card are curved, instead of being straight. (00:16:23)
Other mistake: When Jaden realises his arm is fading away, the Elemental Hero Clayman card shown on his duel disk is shaded orange. It should be shaded yellow, as it is not an effect monster, and effect monsters are shaded yellow. The same mistake occurs around a minute when the Shadow Duelist says, "It's your move, but make it count, it may be your last." (00:17:28 - 00:18:22)
Continuity mistake: Jaden activates the spell card Mirage of Nightmare, and then places two cards face down. Later in the scene, Jaden activates the trap card Mirror Force, so when that leaves the field, only one other card is face down on Jaden's side of the field (not counting Mirage of Nightmare). But a couple of seconds later, when the Shadow Duelist brings Terrorking Archfiend back to the field, Jaden has three face-down cards, even though he should only have one card face down and one card already activated. (00:02:12 - 00:03:36)
Continuity mistake: When the Shadow Duelist draws the Skull Archfiend of Lightning card from his deck, he has his right hand raised so that he can look at the card. When the shot cuts, his right hand is suddenly lowered. (00:06:28)
Continuity mistake: When the shadow dome shrinks down and disappears, Jaden puts his left hand on the coffin that Alexis is in. When the shot cuts, he suddenly has both hands on the coffin. (00:18:57)
Duel and Unusual Punishment - S1-E7
Continuity mistake: After Chumley returns from Chancellor Shephard's office, in the shot where Jaden says "Well, you did lead us to the cafeteria", Jaden is holding six cards in his hand. The cards are side-by-side, with each card on top of the other. But in the next shot, the second card is suddenly under the first card. He also loses one of the cards in between shots, with there being six cards in the first shot, then five in the next. (00:05:00)
Duel and Unusual Punishment - S1-E7
Continuity mistake: When Chumley is standing on the cliff, Alexis approaches from behind. When he hears her, he turns his head around to face, while his body remains facing the edge of the cliff. In the next shot, he has suddenly turned around entirely to face Alexis. (00:05:45)
Duel and Unusual Punishment - S1-E7
Continuity mistake: At the start of the duel, just after Jaden draws his first card, his right hand is positioned higher than his left hand. When the shot cuts, both hands are level. (00:06:25)
Duel and Unusual Punishment - S1-E7
Continuity mistake: On Jaden's second turn, he draws a card from his deck with his right hand, which is higher up than his left hand. Then there is a close-up of the cards in his hands and both his hands are suddenly level. (00:08:25)
Duel and Unusual Punishment - S1-E7
Other mistake: In the close-up shot of the cards in Jaden's hand on his second turn, it is revealed he drew Elemental Hero Clayman from his deck. The Clayman card is shaded orange, but since Clayman is not an effect monster, it should be shaded yellow. (00:08:26)
Duel and Unusual Punishment - S1-E7
Continuity mistake: After Syrus' life points go down to 2600, Jaden places a card face down. The card is positioned directly behind Elemental Hero Avian. But a minute later, after a brief conversation between Chumley and Alexis, the face down card is now more to the left and is positioned in between Elemental Heroes Avian and Sparkman. (00:09:13 - 00:10:26)
Duel and Unusual Punishment - S1-E7
Continuity mistake: On Syrus' second turn, there is a close-up of the cards in his hand. In his left, we can see five cards and Steamroid and Gyroid are the fourth and fifth card on the right-hand side. A few minutes later, after the flashback to grade school, when Syrus activates Polymerization to fuse the two monsters together, they are now the first and second card in his left hand, on the left-hand side. (00:10:32 - 00:14:15)