Baylavim

Naruto's already used his Futon: Rasengan, when he combo'd with Yamato. Chances are he's going to use some other attack, to avoid repitition. I'm actually thinking he'll use Asuma's chakra blade thing: it seems like an appropriate way to show off his new control over wind.

But I could be completely wrong, and he could just Rasengan the shit out of Kakuzu, as you said. Either way, Naruto will prove to everyone he's a total badass again.

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