Upon arriving, Aang's group is welcomed warmly by the citizens of the Northern Water Tribe. Sokka falls in love with Princess Yue, while Aang and Katara master their waterbending skills under master Pakku. Once the Fire Nation armada arrives, Zhao begins his attack while Zuko infiltrates the tribe on his own, capturing Aang while he entered the spirit world to find the dragon spirit to give him the wisdom to defeat the Fire Nation. Coming to his senses, Aang battles Zuko before Katara freezes him. As the battles escalates, Iroh watches Zhao slay the moon spirit Tui, causing the Waterbenders to lose all of their powers and abilities to Waterbend. However, Yue, who was imbued with some of the energy of the Moon Spirit when she was a newborn, sacrifices her life to revive the Moon Spirit. As Zhao is drowned by Northern Waterbenders after Zuko and Iroh leave him to his fate, Aang uses the ocean to drive the armada back. Aang now fully embraces his destiny as the Avatar and prepares to continue their struggle against Ozai. When news of Zhao's death and Iroh's betrayal reaches him, Ozai appoints his daughter Azula to capture both her uncle and older brother while hindering the Avatar in any way before Sozin's Comet makes its return within three years time.