i was trying to figure out who tobi actually is...i seriously had a rough time doing that...tobi in the recent manga said when he took nagato's body...that you were the 3rd sage of the six paths....thats kinda odd....now who was the second....well second could be madara uchiha the real one....as he has the renningan in the manga....so who is tobi....it cant be obito because obito was kakashi's age obviously so he'd be in his teenage just like kakashi when the fourth was fighting tobi who seemed to be a grown up man.....you tell it frm the height etc...and it cannot be kagami uchiha cux we never really got to a gud look at that character at all....so the writer cannot at all make the mistake of putting such a character and hide him frm everyone such a long time cux he needs to giv that twist in the story...and then you notice that he has this black kinda thing on his face just like the zetsu so we knw he is a mixture of this zetsu....as he can just take of his arm and leave that sap dripping just like a zetsu.....so one of this naruto movie naruto time travels bak into time to see his father minato the movie is called the lost tower....so throught that we have an idea that the writer actually has this slight concept of time travel....so i made a few theories...either it could be sasuke....maybe in the final fight between naruto and sasuke naruto sealed all the evil part of sasuke away....but somehow he managed to come bak as in time travel using the name of madara uchiha we see that in the beginning of shippuden sasuke see's the nine tails inside of naruto and the nine tails says your chakra reeks like madara uchiha's and how tobi is always there when sasuke is about to go all out and he goes like what are you going to do now sasuke...maybe he intends him to completely go evil....since he blows his cover in the land of iron by telling zetsu too..its against sasuke's strict "no killing policy" but he then has to kill ppl and his chakra turns even more dark!.....its a possibility....im not really sure abt this theory but there's another possibility that it might be izuna uchiha the only one who knew madara at that time...and the only one considered nearly as strong as him....maybe the next step to acheive the rinnegan is sacrificing oneself...and attain the rinnegan...and then be revived using the same rinnegan...it is a possibility that madara sacrificed himself in the battle with the first achieving the rinnegan and then intended to revive himself...but somehow izuna got revived since madara had completely lost his eyesight and took izuna's eyes so when izuna's eyes were sacrificed he got revived having a rinnegan...! but that theory is also a little vague....what i actually think is true or is the real theory...is that the character tobi actually is madara uchiha....madara uchiha a part of him fused with zetsu...since we see the black zetsu kind of side on tobi's face...madara uchiha the one revived by kabuto said when he was fighting tsunade that hishirama if i knew how weak they were going to become i wouldve tought you how to come back to life....now that sentences is a little weird dont you think...tobi says to konan when they fight that you betrayed me you were suppose to use that jutsu for me(tobi) the one pain used to revive everyone in the village...the Outer path: Samsara of heavenly life technique....neways this can be theory that madara uchiha the real one who sacrificed himself to obtain the rinnegan in the battle with the first hogake actually created the zetsu and fused a part of him with the zetsu...this when done he fought the first the rinnegan when activated he died and was suppose to be revived by his other creation of part of him as tobi himself says im a mere shell of wat i was before....so we knw through all that tobi was going to revive himself it cud possibility by using that technique....and maybe he was the one who took madara uchiha's(the real one) eyes and planted them in nagato cux he was just a mere shell he cudve possibly not activated them in that stage so he gave them to this kid in the hidden village(which was going through war at that time) maybe he knew that he would go through some trauma and the rinnegan would be activated or maybe he is the one who killed his parents or ordered someone to kill them!...it could be a possibility as he said you were the third sage of the six paths the second was madara uchiha himself...and we all knw the first the rikudou sennin...so it could be a possibility since nagato was frm the uzumaki clan madara(tobi) might have guessed that he could be able to withstand the power of the rinnegan and planted it in him....in hopes he would use him to rivive himself and then take his eyes back...it could be a possibility as he said it himself i am just taking whats rightfully mine when he was fighting konan!...But his plans got a little out of order since kabuto had madara's corpse....Also madara seems to knw this tobi as we see in a manga chapter...So what do you think guys?...i got a few theories tell me what you think abt them!