Avatar: The Last Airbender Season 2

After a bittersweet victory in stopping the Fire Nation's invasion of the Northern Water Tribe, Avatar Aang (Gordon Cormier), Katara (Kiawentiio), and Sokka (Ian Ousley) regroup and set out to find the elusive Earth King, hoping to enlist his help in their fight against the formidable Fire Lord Ozai (Daniel Dae Kim). Their journey leads them to the impenetrable city of Ba Sing Se, where the Earth King resides, and along the way, they encounter the young and daring earthbender Toph (Miya Cech), whom they convince to teach Aang earthbending, granting him a third element to master alongside air and water.