In Book Two: Spirits, taking place six months after the Anti-bending Revolution, Korra learns from her uncle Unalaq of her seclusion being set by both Tenzin and her father, causing her to break off with Tenzin and have Unalaq become her mentor.
Following saving Tenzin and his children and seemingly losing her bending of three of the elements to Amon, Korra engages in a battle with Amon where she emerges victorious thanks to her newly acquired airbending, having the other elements restored by Aang and in doing so gaining the power to restore bending as well. She is locked in a secluded cabin that holds her for a short time before she breaks out once it is ambushed by Amon and his Equalists, the group launching an assault on Republic City that Korra and the others are overpowered in, forcing them to retreat until General Iroh and the United Forces come to the city as reinforcements, who are also overwhelmed. Korra afterward discovers Hiroshi Sato's ties to the Equalists, then allowing Asami Sato, Bolin and Mako to live with her, forming a team with the group that Councilman Tarrlok breaks up by arresting the others and revealing himself as a bloodbender in an encounter with Korra where he subdues her.
After saving Bolin and having her first sighting of Amon, Korra's romantic struggles lead to difficulty with the pro-bending team, which the group recovers from to successfully win their match and make it to the finals, where they are defeated and Amon strikes with his group of followers, the Equalists. Korra moves to Republic City to go after him following a brief encounter with Katara, being taken in by Tenzin and meeting both Mako and Bolin before joining their pro-bending team. In Book One: Air, Korra, now seventeen, and having mastered three of the elements, needs to learn airbending from the only living airbending master, Aang's son, Tenzin.