I want Madara to be the final villain. After all he is the most mistrious character in all series. Nothing has been revealed about him, or.. was anything? Do we actually know anything else about him but that his name is Madara and that he fought 1st Hokage and he's got EMS ?
Come to think of it, there were so many discussions and debates about Madara in the manga, yet nothing has been revealed. Neither his powers nor his joinage of Akatsuki has been presented in the manga.
We know absolutely nothing about this person, we know absolutely nothing about his plans and powers, we know absolutely nothing about his true intentions, we know absolutely nothing about his relations with Itachi, Konoha and other villages during the recent years.
Oh wait, no, we have been given a hint: he was a Mizukage some time ago.
Any other mysterious character you know? Danzou? The truth about him has been pretty much revealed. His Sharingan belongs to Shisui Uchiha and we do even know the power of that Sharingan. We know that he has a connection with Orochimaru, oh no wait, he had a connection with Oro, cuz oro is kind of dead now.
Sasuke? Noooo... as Rei Chan has already stated... Sasuke's faith is very predictable. He'll end up as Pein with oen exception - he won't die.
Kabutochimaru ? He's mysterious but he's scrazy. He will never become a final villain.
He'll play a role in Naruto's and Sasuke's development but that's pretty much it. He's gonna fight Sasuke and he's gonna fight Naruto. He's gonna change their minds a little bit, or something like that. But he will never be the one to pull the strings from behind, like Madara. That's what he's obviously been doing during the past 50 - 70 years.
Madara knows he's mysterious. madara knows he's evil and knows what does he want. He does not rush in and he does not express some stupid claims about "how he will kill him and him". He's trying to understand his enemy/rival, and then, he prepares a massive counterattack.
To sum up my long post in case it's hard to read: My vote has gone to Madara

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