The 10 best episodes of Avatar: the Last Airbender, ranked

6. The Avatar and the Fire Lord

This episode has Avatar Roku showing Aang the beginning of the war, and how he failed to stop it. At the same time, Iroh sends a message to Zuko telling him to find the history of his great-grandfather.

Throughout the episode, Zuko and Aang simultaneously learn about Avatar Roku and Firelord Sozin’s friendship, which turned into a bitter rivalry. When they were teenagers, Sozin and Roku were close friends. On his 16th birthday, the fire sages revealed that Roku was the Avatar. He then left the Fire Nation for 12 years to master the other elements.

When he returned, Roku and Sozin resumed their friendship; Sozin was even Roku’s best man at his wedding. But things got bad when Sozin decided to occupy territory in the Earth Kingdom, intending to share “the Fire Nation’s prosperity.” When Roku confronted his friend, Sozin not only defended his actions, but attacked Roku and accused him of being a traitor. Roku easily defeated Sozin and destroyed the royal palace. Instead of killing him, Roku spared his old friend but warned him to not step out of line again.

Twenty-five years later, the volcano on the island Roku lived on violently erupted. Roku stayed and “fought” the volcano while the island’s residents escaped. When it looked like he was overwhelmed, Sozin appeared on his dragon and helped Roku. However, when Roku inhaled the volcano’s poisonous gas, Sozin left him there to die.

Now that Roku couldn’t stop him, Sozin began the war by wiping out the Air Temples, since it was known that the next Avatar would be an air nomad. But we know Aang was not at his temple when they attacked. His disappearance haunted Sozin and his decedents for generations.

Zuko goes to see Iroh and is angry because he already knew about Sozin. But Iroh reveals that Avatar Roku is also Zuko’s great-grandfather through his mother. He then urges Zuko to analyze the struggle between his great-grandfathers and use the lessons of the past to help bring balance to the world in the present. This conversation lays the seeds for Zuko’s turn to good, and his ultimate redemption.