Iron Forged in Fire: Part One - S1-E1
Continuity mistake: After Tony says he is going to use the Iron Man armor to spy on Stane, he and Rhodey goof off some and wrestle. In the first shot of this, you see Rhodey’s arm come on camera and grab Tony’s, as Tony moves his hand up towards his own face. When he does, his arm and hand cast a shadow on his neck and chest. The shot cuts to a side view and suddenly the shadow has completely vanished. (00:15:00)
Triumvirate of Terror! - S3-E8
Continuity mistake: When Joker zaps Wonder Woman and her mother, they are both standing in front of their thrones and fall forwards. But when Wonder Woman stands back up, her mother, still unconscious, is suddenly off to the side and behind the thrones. (00:11:35)
Deliberate mistake: At the beginning, Asajj Ventress is wearing an outfit with a long skirt. When she is rescued from her damaged starfighter by the scavengers, the skirt has vanished. This was done because the animators found the skirt too difficult to animate. This is also why she receives a brand new outfit that never had a long skirt later in the episode. (00:08:20)
Continuity mistake: When Domino is playing pool, in the wide shot, she is shown at the one of the corner pocket sides of the table, with Toad perched on the left corner pocket across from her. When the shot changes to her getting ready to take her shot, she is now standing on one of the side pocket sides of the table, with Toad similarly perched on the corner pocket on the left across from her, only now it would be on the same end of the table where she was originally standing. (00:21:57)
Land of Hold/Penny Henny - S2-E17
Deliberate mistake: When Garfield brings Jon to the broken TV, the scene's animation is still unrendered. (00:01:04)