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Can more than one person be able to bend more than one element?
In the beginning, before the Avatar, the people of the world got their bending abilities from the Lion-Turtles. Avatar Wan was a man who found the 4 lion-turtles and was given the ability to bend all 4 elements.
So does that mean anyone could go and find these lion turtles, and so anyone can be an Avatar or bend more than one element?