Aninals/Spirit Animals

Lion Turtle

The Lion Turtle is a gigantic, ancient creature with the head of a lion and clawed, lion-like feet. He has existed since the beginning of time and therefore predates the Avatar. Possessing immense power and wisdom, the Lion Turtle served as a spiritual beacon where Aang communed with his past selves and, when these efforts proved fruitless, revealed to him the power to bend the energy within oneself. Aang was not the first Avatar to meet one of these legendary beasts, but he was the first in many ages.
Because of the Lion Turtle's age, a large forest has sprouted on its back. It prefers to stay hidden from the world; with his head submerged, he appears as an ordinary island.

Hei Bai

Hei Bai, also known as the Black and White Spirit, is a forest spirit that normally takes the form of a docile panda bear, but can turn into a large multi-armed monster when angered.

Dragons

Dragons are the original practitioners of Firebending and are capable of breathing fire. They taught this ability to the Sun Warriors civilization, a precursor to the modern day Fire Nation. They were also thought to be extinct before Aang and Zuko discovered that two were still alive.

Badgermoles

Badgermoles are gigantic blind mammals which inhabit the Earth Kingdom. Living mostly underground, they were the first Earthbenders, later teaching humans the same art.