I remember a few chapters back that there were specifically 6 Zetzus that were in Sasuke's body. Four of the Zetsu's were used to reincarnated the Hokages and I could have sworn that the 5th Zetsu was taken over by Orochimauru (correct me if I'm wrong). That leaves us with a6th Zetzu still incapacitated! Orochimauru could and might just ressurect either Rin and Obito will go absolutely insane and fall apart when Rin expresses her disgust and pity for what he has become. OR Orochimauru, overhearing what Obito said about Kushina when he and Tsunade arrive on the battlefield decides to give Naruto a surprise Birthday present! That of course will be Naruto's mother Kushina revived with Edo Tensei! Also, let's not forget that there are chakra rods, recievers, and stakes everywhere across the battlefield due to the battle Naruto, Bee, Kakashi and Guy had with Obito and Madara. That could very well be Madara's trump card. He will use the Rinne Tensei again with those rods and revive himself, but will consequently revive everyone else as well. You see the first time Madara he used the jutsu was when he was manipulating Obito to use the jutsu strictly on him and if Obito wouldn't have resited it, he would have concentrated the entire jutsu on Madara. So this time if he is to do the same thing with the leftover Chakra recievers, then he will be reviving everyone else too. Will we see Kushina and/or Rin be revived with Edo Tensei then Rinne Tensei? I hope so! That would be awesome! 
