Well I think its time I got some of my thoughts about who or what Tobi is on the table. A lot has been going on recently so theres tons of information or hints as to what happened to Madara Uchiha and who has become Tobi.
The most prominent theory as to who Tobi is is of course Madara Uchiha. I have the strong urge to disbelieve this theory because it would be incredibly anti-climatic. Kishi has been building up this Tobi character and his connections with Madara for the better part of a year, so if it is simply Madara, that would be a huge let down. This however does not mean that Tobi is in no way related to Madara, as he most certainly is. There is definitely a connection between the two, but I highly doubt its as simple as Tobi=Madara.
Next we have to look at the character of Zetsu. Zetsu has been shown to be the closest person to Tobi and the only person who has known his identity the entire time. I think its also important to observe the split persona that Zetsu has. His white side is immature and comical, while his black side is always serious. We have seen this same dichotomy with the character of Tobi who at times has been a comedian, and at other times has been serious. I think this is an important connection between Tobi and Zetsu.
Third we must look at the abilities that Madara possesses. His most notable things are the sharingan, and a space/time ability similar to the technique we've seen Kakashi use. Everyone seems to hate associating anything about Obito with Tobi, but I think its naive to ignore the apparent similarities between Tobi's space/time tecnique and Kakashi's. As we know Kakashi's sharingan came from the left eye of Obito. We also know that Tobi tries to collect "good eyes" whenever possible.
We must also account for time when talking about Madara. This is a man who was already in his 20's at the time Konoha was founded. This was a time prior to the birth of characters like Danzo or Hiruzen. If Madara is still simply Madara, he would be over 100 in age, yet he looks nowhere near that old. Theres the option that hes using a forbidden technique like Orochimaru to prolong his life, but I think thats not true.
So given these facts here is a theory I have come to.
1.) Zetsu's ability that has given him his appearance, and his need to devour bodies, directly result in a prolonged life and perhaps the ability to avoid aging. If he is as old as I think he is, he would have been well aware of what was going on between the Uchiha and Senju as well as the creation of Konoha. We have also seen that Zetsu likes to watch battles. What battle would be better to watch than Madara Uchiha challenging Hashirama Senju for leadership of Konoha? It would certainly be the most epic battle the ninja world had seen since the Sot6P battled the Juubi. So if Zetsu was alive at this time, we would have likely observed this battle. This brings us to 2.
2.) How is "Madara" still alive? I believe that after his battle with Hashirama, Madara was in a state of near death, or even death. Zetsu then revealed himself to Madara and offered his help. As we saw when Tobi lost his left arm he was able to rebuild it using the material that makes up Zetsu's body. I think this is because Zetsu has artificially rebuilt the parts of Madara's body that were lose during the battle. This would have been an extensive process and I think part of Zetsu sort of "merged" with Madara. This would explain the split personality we have seen in Madara, though it would be a much lesser extent than that which we see in Zetsu. This is also why Madara has aged much less than anyone else around him.
3.) The merging with Zetsu left Madara in a much weakened state. Because the body had become tainted, and he possibly lost an eye in the battle against Hashirama, Madara lost the ability to use the EMS. If he did lose an eye I believe it is the right one, which is the one he leaves open through his mask. Over the years he has used eyes of other Uchiha members as replacements. The eye he currently uses belongs to Obito, and thus he gained the ability to use a unique space/time technique that belonged to it. If theres one thing I'm sure about, its that Tobi switches eyes. Tobi really wanted the eye of Shisui Uchiha that Danzo possessed for the mind controlling technique it had. I think he planned to transplant it into himself until Danzo destroyed it.
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Thats one theory. Heres another. ^_^ (I'll make it brief)
Madara really DID die after fighting Hashirama Senju. Zetsu however used his ability to create a perfect clone and then used an ability similar to Edo Tensai to bring back Madara's soul, and he attached it to the clone body. This results in Madara becoming a shell of his former self, the loss of the EMS, and the need to borrow other Uchiha eyes. This explains the split personality and the ability to use Zetsu to replace body parts.
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And a third theory while I'm at it. (Damn you Kishi! >.<)
I have a strong feeling that Kabutomaru summoned Madara's body in his last coffin. This would mean that Madara's soul is truly dead. My head hurts though....so I'm going to quit here. ^_^
Discuss!
The most prominent theory as to who Tobi is is of course Madara Uchiha. I have the strong urge to disbelieve this theory because it would be incredibly anti-climatic. Kishi has been building up this Tobi character and his connections with Madara for the better part of a year, so if it is simply Madara, that would be a huge let down. This however does not mean that Tobi is in no way related to Madara, as he most certainly is. There is definitely a connection between the two, but I highly doubt its as simple as Tobi=Madara.
Next we have to look at the character of Zetsu. Zetsu has been shown to be the closest person to Tobi and the only person who has known his identity the entire time. I think its also important to observe the split persona that Zetsu has. His white side is immature and comical, while his black side is always serious. We have seen this same dichotomy with the character of Tobi who at times has been a comedian, and at other times has been serious. I think this is an important connection between Tobi and Zetsu.
Third we must look at the abilities that Madara possesses. His most notable things are the sharingan, and a space/time ability similar to the technique we've seen Kakashi use. Everyone seems to hate associating anything about Obito with Tobi, but I think its naive to ignore the apparent similarities between Tobi's space/time tecnique and Kakashi's. As we know Kakashi's sharingan came from the left eye of Obito. We also know that Tobi tries to collect "good eyes" whenever possible.
We must also account for time when talking about Madara. This is a man who was already in his 20's at the time Konoha was founded. This was a time prior to the birth of characters like Danzo or Hiruzen. If Madara is still simply Madara, he would be over 100 in age, yet he looks nowhere near that old. Theres the option that hes using a forbidden technique like Orochimaru to prolong his life, but I think thats not true.
So given these facts here is a theory I have come to.
1.) Zetsu's ability that has given him his appearance, and his need to devour bodies, directly result in a prolonged life and perhaps the ability to avoid aging. If he is as old as I think he is, he would have been well aware of what was going on between the Uchiha and Senju as well as the creation of Konoha. We have also seen that Zetsu likes to watch battles. What battle would be better to watch than Madara Uchiha challenging Hashirama Senju for leadership of Konoha? It would certainly be the most epic battle the ninja world had seen since the Sot6P battled the Juubi. So if Zetsu was alive at this time, we would have likely observed this battle. This brings us to 2.
2.) How is "Madara" still alive? I believe that after his battle with Hashirama, Madara was in a state of near death, or even death. Zetsu then revealed himself to Madara and offered his help. As we saw when Tobi lost his left arm he was able to rebuild it using the material that makes up Zetsu's body. I think this is because Zetsu has artificially rebuilt the parts of Madara's body that were lose during the battle. This would have been an extensive process and I think part of Zetsu sort of "merged" with Madara. This would explain the split personality we have seen in Madara, though it would be a much lesser extent than that which we see in Zetsu. This is also why Madara has aged much less than anyone else around him.
3.) The merging with Zetsu left Madara in a much weakened state. Because the body had become tainted, and he possibly lost an eye in the battle against Hashirama, Madara lost the ability to use the EMS. If he did lose an eye I believe it is the right one, which is the one he leaves open through his mask. Over the years he has used eyes of other Uchiha members as replacements. The eye he currently uses belongs to Obito, and thus he gained the ability to use a unique space/time technique that belonged to it. If theres one thing I'm sure about, its that Tobi switches eyes. Tobi really wanted the eye of Shisui Uchiha that Danzo possessed for the mind controlling technique it had. I think he planned to transplant it into himself until Danzo destroyed it.
_________________________________________________________________
Thats one theory. Heres another. ^_^ (I'll make it brief)
Madara really DID die after fighting Hashirama Senju. Zetsu however used his ability to create a perfect clone and then used an ability similar to Edo Tensai to bring back Madara's soul, and he attached it to the clone body. This results in Madara becoming a shell of his former self, the loss of the EMS, and the need to borrow other Uchiha eyes. This explains the split personality and the ability to use Zetsu to replace body parts.
_________________________________________________________________
And a third theory while I'm at it. (Damn you Kishi! >.<)
I have a strong feeling that Kabutomaru summoned Madara's body in his last coffin. This would mean that Madara's soul is truly dead. My head hurts though....so I'm going to quit here. ^_^
Discuss!