It will not be a single person but a joint effort, I see Hashirama facing Madara, while Naruto & Minato(possibly Naruto & Sasuke) face Obito, while the remaining Kages & Sasuke/Orochimaru's party assist the alliance in stalling the Juubi, once the Masterminds are defeated(with possible defection of Obito), a group effort will resolve in the defeat & sealing of the Juubi(the method of this really depends on if Kishi follows through on the Naruto & Sasuke duel); if Kishi decides to end the series with Naruto facing Sasuke, then somehow I see Kishi inventing some way to return the Bijuu to their seperate states, if he decides to redeem Sasuke before a final duel, then I see the Juubi being sealed into Naruto & him becoming the second Sage of the Six Paths, I also see a possible scenario with Sasuke's death leading to Naruto's gaining of the Rinnegan thus enabling the second Sage plot-line, the only real mystery to me is where Orochimaru's path leads.shodaimeicon: