Shortly after Toph Beifong joined Team Avatar, Azula, Mai, and Ty Lee relentlessly tracked them down in a tank train. They eventually exited the tank train on mongoose dragons and continued to attack the group on the creatures. After Team Avatar split up, Azula had Mai and Ty Lee pursue Sokka and Katara, while she pursued Aang.
Mai and Ty Lee were able to successfully traverse the Nan Shan River to reach Sokka, Katara, and Appa, as the mongoose dragons were capable of skimming the water's surface.
While searching for Aang on mongoose dragons later on, the trio encountered the Kyoshi Warriors and Appa, emerging victorious in the ensuing battle.
The mongoose dragon is a cross between a mongoose and a large-scale basilisk lizard. It is very similar to the plumed basilisk in its markings and raised chest, as well as the few plumed areas of skin above the head.
These massive lizards are approximately fifteen to twenty feet long from snout to tail, with bright yellow eyes. They act as modes of transportation, ridden like horses, though they are far more versatile.
Their quick, mongoose-like reflexes help them to dodge almost any attack, and their lizard-like abilities enable them to quickly traverse just about any obstacle; they have displayed the ability to scale walls and skim over bodies of water. Riding this animal requires some habituation, especially when it stands on its hind legs.
This enormous reptile most closely resembles the green plumed basilisk lizard. The markings and raised crests of the latter are very similar to those of its giant Avatar World counterpart. The green plumed basilisk also has the ability to run short distances atop water.