Sozin's Comet (1): The Phoenix King - S3-E18
Continuity mistake: When Aang is waking up on the giant lion turtle, he is not wearing shoes in the first shot, but in the next shot, he is. (00:22:35)
The Southern Air Temple - S1-E3
Other mistake: When the gang is in the Hall of Statues of Past Avatars, Katara points out the avatar cycle pattern of statues and Aang zeroes in on Roku's statue. The earthbender avatar statue next to Roku is of an unknown man with a sword, not Kiyoshi. (00:12:50 - 00:13:35)
Avatar Day - S2-E5
Continuity mistake: When the village leader switches the wheel of punishment to Community Service, it is on the space next to Boiled in Oil. However, all of the other shots of the wheel have another section in between these two.
Bitter Work - S2-E9
Continuity mistake: When Iroh draws the symbols of the Four Nations in the sand, there is grass on the left side of the Earth symbol in the close ups. In the shots that show all four symbols, the grass is gone. (00:14:25)
Other mistake: When Azula attacks The Western Air Temple, there is a close up shot of her when she says that she is about to become an only child. Pay attention to the smoke coming from the airship behind her, especially above her head: it doesn't move. Even if this was remotely possible, it does move when the camera zooms out, making it a mistake nonetheless.
Character mistake: When Jet tells Katara and Aang to waterbend the water from underground in the geysers, Katara states that she has never waterbent on water she couldn't see before. However, six episodes prior to this, in 'The Warriors of Kyoshi', she waterbends the water out from Aang's lungs to save his life.
Suggested correction: That was a moment of desperation on her part, and she probably doesn't think of it/think she can do it again without the same desperate impetus, Furthermore, the water in Aang was only a small amount and very close anyway.
Regardless of if she did it in desperation or not, she did use bending on water she didn't see. The mistake isn't suggesting anything about Katara's ability to waterbend unseen water, the mistake is only in regards to the statement Katara made about never using bending on water she can't see. And for Katara to forget the one time she used bending on water she didn't see would qualify as a character mistake as well. Now if she made the statement "I don't think I can do this" or "I've never used bending on underground water", etc, that would not be a character mistake.
Bato of the Water Tribe - S1-E15
Other mistake: When Katara is behind Sokka and he is speaking she leans back and as she does her eyes stay in the same place while her head moves, then it fixes itself. (00:16:20)
Continuity mistake: When Katara is trying to heal the wounded earthbender, she gives Sokka the idea to take down The Drill from the inside. Sokka then stops her from saying anything while she is sitting down, and she is wearing her necklace. When she stands up in that same shot, the necklace is gone, like they forgot to animate it. (00:07:35)
The Southern Air Temple - S1-E3
Continuity mistake: When Gyatso is laughing in Aang's flashback, he is missing quite a few teeth. But when Aang finds his skeleton, all his teeth are still in place.
Avatar Day - S2-E5
Continuity mistake: When we first see Aang in the stocks, Sokka advises him to use his Airbending to escape and begins "imitating" Aang's kata. During one pose, we see Sokka is wearing the boomerang, or at least the sheath it was in, that he had to leave behind at the beginning of the episode. He wasn't wearing it before, isn't wearing it after, and doesn't actually get it back until the climax. (00:02:09 - 00:06:33)
Other mistake: When Aang emerges from the water on the giant sprout in The Avatar State, the arrow on his head is not glowing.
Audio problem: At the end of this episode, Aang tells Katara that forgiveness is the first step you need to begin healing. But if you watch closely, his mouth isn't moving at all when he says this.
Plot hole: Because Katara lost her mothers necklace, Aang made one for her and she puts it on. But when they reach The Fortunetellers village, Katara is not wearing the necklace, and no one notices, not even Aang.
Sozin's Comet (4): Avatar Aang - S3-E21
Continuity mistake: Throughout the entire show, Aang's eyes are grey, but in the last three episodes (Sozin's Comet Part 2, 3 and 4) they are suddenly brown.
Continuity mistake: When Zuko and Iroh are walking towards Azula's ship, the gold flame insignia on the imperial firebenders' uniforms switches directions between shots.
The Tales of Ba Sing Se - S2-E15
Other mistake: The Tale of Sokka: When Sokka delivers his final haiku to the girls, he inadvertently adds an extra syllable to the final line. In the close-up of him counting his fingers, the iris of his left eye is rendered over his hand. (00:14:42)
The Desert - S2-E11
Other mistake: At the start, when Toph says, "I can hardly feel any vibrations out here," Aang moves his head, and it briefly duplicates. Right after that, Aang seems to shift into another position without any animation, most noticeable with his head and face. (00:01:56)
The Western Air Temple - S3-E12
Other mistake: When Sokka and Aang put Toph's feet into the fountain, Aang's hand (the one holding Toph's left leg) is incorrectly drawn with a blue glove on it. The glove is gone in the next shot. (00:15:29)
The Crossroads of Destiny - S2-E20
Continuity mistake: When Aang enters The Avatar State, the arrow on his head is glowing, as it should be. But in one shot showing his backside as he rises into the air, the arrow is not glowing. (00:19:44)
Continuity mistake: When Katara is sitting on the dock at the end, she is wearing her blue gloves on her hands, but then when she stands up and walks over to Aang, she is not. (00:22:26 - 00:22:52)
