Quote Originally Posted by Death BOO Z View Post
he can shadow clone. he has all the time in the world. if he put his mind to it, he could start a family in a different village and have his clone live there as a non-ninja for the rest of it's life.
the shadow clone uses lots of chackra, it is forbidden because many of the users would deplete most of their chackra and die in the process of learning/using it.

naruto was able to use the shadow clone because of the kyubi itself, everytime he was about to dry out of chackra the kyubi would give him part of his chackra as a way to maintain the body from dying, thus killing the kyubi in the process.