Tobi Identity theory.
I Just read Blaze Releaseas' Thread about the rinnegan not needing Senju DNA.
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And I was thinking that while I never really spent too much thought on who tobi was, I'm now thinking that it is Izuna Uchiha.
I'm not going to back it up with a tonne of links and evidence simply because I'm far too lazy I'll just say this.
Tobi whilst mascarading as Madara seemed certain that Madara cared and loved for Izuna, despite taking his eyes.
Tobi knows an awful lot about Madara's Past and History.
There's a good chance Tobi's Eyes are Implanted, when you see all the eyes in the Jars etc. and never see him release sharingan, even though you never see Itachi do so but he would have to when he had a long strenuous fight, so the same should be for tobi after his fight with Konan.
Izuna not only Rivaled Madara, but probably admired him also, as younger brothers often do, which would be a reason for him to willingly give up his eyes to Madara, which would explain why he posed as Madara.
Izuna was said to have died during battle, but perhaps only fatally wounded, and Madara Saved him and immortalized him using Zetsu, Planning for the future.
I'm sure I could think of some other reasons but I cba, let me know what you think,
P.S. don't be too bitchy this is just a five minute thought on the matter.
