Toph Beifong, also known as Toph, was a blind earthbender from Gaoling and the daughter of the Beifong family. She went on to become the earthbending teacher of AvatarAang.
Toph first encountered Aang and Sokka at Earth Rumble VI, when Xin Fu, the host, announced that some previous contenders had withdrawn from the competition and offered their spots to members of the audience. Aang and Sokka enthusiastically volunteered themselves and defeated Toph by the final match. Based on their encounter, Aang had determined that Toph was meant to be his earthbending teacher, but Toph left before they could talk further.
Following the tournament, Toph returned to the Beifong family estate. That night, she was visited by Aang and Sokka, but Aang was promptly captured by Xin Fu, who intended to hand him over to the Fire Nation. Together with Sokka and Katara, Toph defeated Xin Fu and freed the Avatar from his abductors.
After Toph and the group left Gaoling, they traveled to the Misty Palms Oasis in order to deliver vital information to Professor Zei.
Along the way, Toph taught Aang basic earthbending. On one occasion, Toph was offended by a comment Aang made toward her, causing them to engage in a bending fight. Once Aang knew some earthbending, the two of them had to battle off a group of sandbenders who where attempting to steal Appa.
When they met Zei and gave him the plans, he told them that in order to interpret the plans, he had to go to Wan Shi Tong's secret library. Thus, Team Avatar set off into the Si Wong Desert to find the location of the lost library. When they arrived, Aang, Sokka, Katara, and Zei entered the building while Toph, because she could neither see nor read, remained outside with Appa.
While Toph was outside, the library began to sink into the sand. Using earthbending, she halted the library from descending completely until Aang, Sokka, and Katara had safely made it out, escaping Wan Shi Tong's clutches. However, sandbenders arrived at the same time and captured Appa. Focusing all her energy on stopping the library from sinking, Toph was unable to help the flying bison this time and he was abducted. She informed the others when they emerged.
Without Appa, the gang was forced to make their way through the desert on foot. When they arrived at Ba Sing Se, they met a peculiar tour guide named Joo Dee who showed them their new house in the Upper Ring. When they asked to be taken before the Earth King, she brushed off their request, much to their frustration.