Deliberate mistake: There is a shot of Alexis getting blasted with electricity when Etoile Cyber is attacked by Sparkman. This same shot is reused later in the episode when she attacked directly by Elemental Hero Thunder Giant, as the electricity and Alexis' position in the shot is the same. (00:12:20 - 00:18:36)
Head in the Clouds: Part 1 - S3-E7
Deliberate mistake: Adrian walks outside the Obelisk Blue dorm to see Chazz standing on a glass platform held up by four cables on each corner, which are attached to a helicopter flying above. Adrian then realises he is standing on a glass platform, held by cables and attached to a helicopter. There is no way he wouldn't have noticed this; he should've seen the cables, heard the helicopter and felt the glass platform beneath him when he walked onto it, even if it makes for a cool reveal. (00:12:55)
Head in the Clouds: Part 1 - S3-E7
Deliberate mistake: Chazz and Adrian take part in a duel where they stand on glass platforms that are suspended in the air, held by helicopters flying above them and are positioned at least a hundred meters apart. They appear to have no problem communicating back and forth, despite the large distance between the two and the helicopter rotors loudly spinning above them.
Inter-Dimension Detention - S3-E16
Deliberate mistake: When the Harpy trio attack Sapphire Pegasus, there is shot of them taking a swipe at him one at a time. This shot is repeated a few seconds later, as the body movements from all the characters are exactly the same. (00:12:12)
Farewell, Duel Academia! The Path Judai Chooses - S4-E2
Deliberate mistake: When Sartorius walks over to his bedroom window, the tarot card that he sees wedged underneath the window doesn't appear until it is first shown in the close-up shot. (00:09:03)
