Green dragon

This green dragon was a female dragon that lived during the period of time before the Hundred Year War. She eventally laid one known egg.

History
At some point during her early life, this dragon found a mate, made a nest in a high mountain located in the Fire Nation, and laid an egg. The location of her nest was mapped out by a cartographer and sold at a cheap price. One of these maps fell into the hands of poachers, while another fell into the hands of Kuzon and his friend, Aang.

Some time after this, her egg was threatened when the poachers distracted her. One of the poachers lured her out of her cave, allowing the others to grab her unborn child. Luckily, however, Avatar Aang and Kuzon stumbled upon the poachers, and, using Kuzon's firebending abilities, tricked the poachers into thinking she had returned. They ran off, but her egg was nearly smashed, when she returned and knocked it out of Aang's hands, incorrectly assuming they wanted to steal her egg.

Luckily, Aang caught it just before it hit the ground, convincing the mother dragon that they were no threat to her or her offspring. She was grateful, but refused to take them for a ride as Kuzon hoped.

Trivia

 * There were six known dragons with her introduction: Sozin's dragon, Fang, Ran and Shaw, herself, and her child, though it was not yet born during "Dragon Days".
 * She is the only known dragon whose color was not red or blue.
 * Unlike other dragons, this one has two sets of wings: the main flying pair and a secondary, smaller pair just below them, whose use were unknown.