Eel hound (Earth-8138)

The eel hound is a species of quadrupedal animal found through the Earth Kingdom that is used as beast of burden and efficient transportation over land and water.

History
Hours before the end of the Cold War, Piandao provided an eel hound for Aang, Suki, and Kakashi Hatake to transport them to Ozai's airship base to stop the Fire Lord's airship fleet. The eel hound crossed a piece of land and swam to the base, leading its riders to depart to the fleet.

Physiology
Eel hounds are large and amphibious, and as such, they are capable of thriving on land and sea, as well as swimming and running at high velocities. Members of the species reach eight feet tall and twenty-five to thirty feet long. They have dark, green skin, with scales, and a lighter underbelly.