Zuko, aboard his ship, was in pursuit of Aang, Kya, and Sokka, when a sea serpent took interest in his ship, allowing the trio to escape the scene. His accompanying soldiers either fled or fainted, but Zuko calmly prepared to face the creature.
Zuko later entered the Fire Nation base with the head of the sea serpent, having successfully defeated it. He interrogated Sokka, who had been captured, but only received insults such as "scar boy". Kya was soon brought to him as well, but refused to reveal Aang's whereabouts. When Aang appeared, Zuko immediately attacked him. Ignoring a warning from a soldier that the scaffolding on which they stood could collapse, Zuko proceeded to battle Aang. When it eventually collapsed, they moved to the defaced Avatar's head. There, Zuko managed to corner him, but was caught off guard when Aang threw himself off the statue to activate the Avatar State and subsequently blew him off. Aang caught Zuko before he hit the ground, but then let go of him when he saw Kya and Sokka in trouble, causing Zuko to hit a wall face first before he landed on his pet hawk.
Zuko was saved from falling to his certain death by Aang; Aang performed a similar action twice in the actual series.
Zuko possessed a pet hawk, who was supposed to be Momo's "arch-nemesis", mirroring Aang and Zuko's relationship. Though Zuko's hawk did not make it into the actual series, Hawky the messenger hawk was created from the concept and fought with Momo.