Zhao leads the Fire Nation into the North with a bold plan to weaken the Water Tribe. When the battle takes a dark turn, Aang enters a powerful state.

In captivity, Aang meets a king with a taste for games. To find their friend, the siblings must navigate a dark tunnel — and put their differences aside.

News of a traitor puts the trio at odds in Omashu, where a mechanist and rebels with a charming leader muddle their plans to protect the Earth Kingdom.