I THINK I figured something out...A question and a theory.
Orochimaru is taking Sasuke to "The one who knows everything", Sasuke is wondering about clan and villiage loyalty, Madara is next to impossible to beat and the White Zetsu Army is still out there... This points to one thing. Orochimaru is taking Sasuke to see Hashirama Senju. Before people say he was sealed and the Edo blah blah can't revive this and that remember these clues. Orochimaru told Sasuke he was taking him somewhere he knows well, and one place that could be is the Akatsuki hideout where Hashirama's "live clone" in the tree is located. That scroll could be a jitsu to revive him. This would not be an ET revival because this thing is alive. If they can pull Orochimaru out of a clump of cells and a curse seal what could they do with a living cell body?
The Question: The "rule" with the Edo T. is you can not revive a person's spirit who have already been sealed in some way, thats why they couldnt revive the first, and Second Hokage during the world war because the 3rd had already sealed them back in the day. Well, when the 9 tails attacked the village Minato sealed himself with the 9 tails Yin chakara using the Reaper Death Seal yet when Orochimaru fought the 3rd back in the day he used E.T. to revive the 1st and 2nd hokage BUT he also started to revive the 4th Hokage but the 3rd stopped him (of course before the coffin opened because the looks would of given away he was Naruto's father too soon). How could he revive him if he was already sealed from before?