In 100 ASC, an Empire-class battleship was used as the flagship of the Fire Nation fleet attacking the Northern Water Tribe. Iroh and Admiral Zhao boarded the vessel, and as the siege progressed, they often discussed their plan of attack on the upper deck. After Zuko's ship was blown up by a group of pirates, the young prince stowed away on the admiral's ship as it embarked for the North Pole, hoping to capture the Avatar there. Iroh secretly assisted Zuko, and used the pretense of being Zhao's adviser to inform the prince of the navy's movements. Once the vessel reached its destination, Zuko left the ship by lowering a small boat into the water.
Hahn, disguised as a Fire Nation marine, eventually gained access to the battleship. He attempted to ambush Zhao, but this effort ended in an abrupt failure, and he was thrown overboard. Later, as a merged La and Aang launched an offensive on Zhao's fleet, the flagship was pushed around in the rough seas.
Zhao's Empire-class flagship was a colossal vessel approximately twice the length, width, and height of a standard Fire Nation cruiser, the primary warship in the Fire Navy's arsenal. The Empire-class ships have three smoke stacks instead of two, a different and larger conning tower with several additional large decks at its base, and an ornate gilded rostrum, an emblazonment that is also on Azula's royal barge. Furthermore, it sported a Fire Nation flag which was much grander than the one flown on the standard cruiser.
- ↑ 1.0 1.1 "The Beach". Katie Mattila (writer) & Joaquim Dos Santos (director). Avatar: The Last Airbender. Nickelodeon. October 19, 2007. No. 5, Book Three: Fire
- ↑ "The Siege of the North, Part 1". Aaron Ehasz (writer) & Lauren MacMullan (director). Avatar: The Last Airbender. Nickelodeon. December 2, 2005. No. 19, Book One: Water
- ↑ 3.0 3.1 "The Siege of the North, Part 2". Aaron Ehasz (writer) & Dave Filoni (director). Avatar: The Last Airbender. Nickelodeon. December 2, 2005. No. 20, Book One: Water