Our next topic..... Kitsunes
In early Japan, there was a deity named Inari that created intelligent foxes that he let roam the earth. Each one had a unique and specific title that was tied to the earth in some way, shape, or form. There was a sound, thunder, forest, mountain, ocean, river, earth, wind, fire, spirit, celestial, and dark kitsune. The only reason why they are so powerful is because of their connection to the Deity, who lived to trick people himself or send his pets to do it for him. Another reason why their so powerful is because of their tails. The more they have, the more powerful they are. The limit is 9 btw. Lastly, whenever they go into a human body and become one with you like every other spirit, you'll have the ability to use some of their elemental abilities. No, you can't use their abilities to become aang, but you can manipulate them to a certain extent. Moving wind with a thought, spreading fires that have already started, etc.
Warning: The majority of them ARE tricksters. So if you wish to summon one, protect yourself at all times.