Butchered the original characters. I know it is an adaptation and not an exact remake but why completely flatten different characters (Sokka, a bit of Aang, and definitely Katara) and ruin their complex development arcs. Largely important plots were completely removed leading to weird plot holes, the writing is horrible and FEELS like bad acting on a stage (reminds me of the Ember Island Play episode from the series). The costumes look too clean, but that is something that isn't really as big of a deal as the rest. Overall, the only thing they did right was Zukko's character and the visual effects. They dulled almost all of the characters' personalities; Gyatso was weak, Aang was bland lacked childishness, Sokka was emotionless and lacked in some of his bad traits (like his sexism, which was such an important character element BECAUSE we get to watch his development as he learns to grow out of it), Katara was boring and didn't have the same passion, and Iroh was bland as well. It's like the writers didn't even watch the original show. Hope they fix it if they make another season. You'll like it if you've never seen the show before. Not sure how so many ratings are so high, my guess is the people writing the reviews have never seen the show.