He has to be someone that will surprise Naruto.
He has to be someone with huge chakra reserves since his lone Sharingan is enough to control six tailed beasts.
He has to be old enough to be an adult during his attack on Kushina.
He has to be an opponent that will mirror Naruto like in every one of his big fights.
He has to be someone with a connection to Orochimaru, due to how much he hates/fears him.
He has to be...
You must be registered for see images