Avatar: The Last Airbender 2×06 “The Blind Bandit”
In search for an Earthbending teacher for Aang, the kids go to an underground Earthbending tournament called Earth Rumble 6, where they encounter Toph, a blind but powerful Earthbending girl. After seeing her unique style of Earthbending, Aang wants Toph to become his teacher, but there are complications with Toph's family.