Uchiha Obito is Real Tobi
The very fact that Uchiha Obito himself is still alive gave the fans a great deal of shock however further on revealing that he is connected to original Uchiha Madara and is stuck to his plans waved another tide of silence.
However, further on it can be easily predicted the story of Obito that has been playing long behind the curtain. The man who is so much sought after – Tobi who started the Fourth Great World War and captured 7 jinchurikis. Tobi is thought to be someone who is there but actually he does not even exists.
In the proceeding chapter we shall see Tobi tagging Madara as his teacher (Sensei). So what is really going on? Well Tobi is a mixture of two to three forms of life. It is a bit complicated to understand in this way. Just as a simple talker as Kakashi it can be explained in simple terms.
Tobi is originally the body of Uchiha Obito who possesses the same Sharingan as that in the eye of Kaksahi. However, as per the incident long ago during the battle half of the body of Obito was completely crushed under the rocks. Obito still is an Uchiha and from various accidents we see his body is repaired. Just like when Tobi attacked Danzou and two of his personal guards ambushed him he cut of his left arm and a white fluid poured out of his body, later on his arm was repaired. Also during the fight of Tobi with indomitable Fourth Hokage – Namikaze Minato his arms was tear apart because of Rasengan and a white fluid substance came out.
No doubt that it is the body of an Uchiha and that the person we see is Obito. It can be easily predicted that during the event when Obito’s body was crushed Zetsu might have rescued the body.Furthermore Zetsu would have fused some part of his body with Obito’s crushed body to make him survive. And Madara would have planned and implanted Izuna Uchiha’s soul within the Uchiha body that furthermore carried the plans of Madara. It is possible that Zetsu might have implanted the soul in Obito’s body. Furthermore as there is no sign of the origin of Zetsu, it is safe to assume that Zetsu is also one of evil Madara’s own creation to carry on his will of the pride of Uchiha’s.
So in all Tobi is body of Uchiha Obito, fused with Zetsu and with a soul of Uchiha Izuna, who was taught by his elder brother Uchiha Madara.