Tobi, not a theory but a thought.

[Chishiokage]

Ok way back in the day when Tobi used his Izinagi on Konan I started thinking of what the Izinagi really takes to use it. You need Uchiha and Senju genes. This got me thinking that it very well could be possible for Tobi to be some sort of Offspring of both. Of course I stopped thinking this because I didn't have evidence to even come close to saying that's what he is. But it is a possibility though very unlikely.
But if somehow he were to be of both clans maybe its possible that the Senju rejected him in some sort of way, and maybe even the Uchiha did as well. This would result in Tobi feeling the way he is about who he is and that might be why he says he's nobody. And the possibility of Madara befriending him or well using him because of this is also possible.
I honestly don't think this is in fact the truth it seems it would actually be a little to deep for the character and not to many people would really see it coming and I doubt Kishi would think about this that way. But it is possible.
Anyway I hope no one gets mad at this thread this is not really what I believe is true its merely a thought. And very very unlikely.

 

[mistype]

You don't need Senju-cells to use Izanagi.

 

[Zoro..]

He might be Madara's nephew and Madara's brother had a baby with a senju anywasy nice theory or thought

 

[~Yubel~]

Why do you make a thread then doubt yourself? No, i don´t think tobi is a offspring but rather a guy who just planted some senju cells into him.

 

[Punk Hazard]

You don't need Senju-cells to use Izanagi.

yes you do

and yeah, either tobis a hybird offspring or he implanted zetsu parts in himself

the second one seems likely since we've seen a mysterious white liquid coming from his body several times

 

[Diottcas]

You don't need Senju-cells to use Izanagi.

Umm yes, yes you do sir

 

[Lord Snow]

I still think tobi is zetsu.

 

[Deadshot]

You don't need Senju-cells to use Izanagi.

You dont need senju cells but to To make full use of Izanagi, users must also have the genetic traits of the Senju, who are also descended from the Sage. Partially for this reason Danzō had some of Hashirama Senju's DNA transplanted into his arm, which had the added benefit of increasing his physical energy and vitality as well as access to Wood Release which could be used to subjugate tailed beasts. Tobi also makes use of Hashirama's DNA, though he claims to have gained control of it, unlike Danzō.

 

[Dr Strangelove]

He could someway be related to Madara.

 

[narutownsyouall]

thats possible haha! romeo and juliet type situation! youll never be with a uchiha in your entire life! we are Senju's!!

 

[Chishiokage]

yes you do

and yeah, either tobis a hybird offspring or he implanted zetsu parts in himself

the second one seems likely since we've seen a mysterious white liquid coming from his body several times

I've seen a lot of people mention the Zetsu thing and I'm not sure if the white substance is from him having zetsu parts. He was Poisoned by the insects though I doubt they could have made his arm react like that. I'm not sure if it is something to do with a zetsu I do however like that thought though. And hopefully he is somehow connected to the zetsu.

 

[Phace]

Tobi is Obito Uchiha. kakashi's old teammate thought dead

 

[itachiEMS]

Tobi is Obito Uchiha. kakashi's old teammate thought dead

and we saw him crushed this has been debated over countless times but he can be an offspring of both yeah

 

[evilmayo]

Tobi is Obito Uchiha. kakashi's old teammate thought dead

if thats true then when kakashi died cause of pain.... and he was being resurrected..... why did kakashi wave good bye to the kid/dead orbito before coming back to life from pains rebirth jutzu.... you cant grow up if your dead/kid soul is still in the dead world... lol

 

[Gutsy]

He waved goodbye to his father

 

[evilmayo]

He waved goodbye to his father

re-watch it... he waves bye to orbito and rin also... trust me... its there

 

[natssuu]

Yeah, he has both. He's an Uchiha who has Hashirama's cells. That's why he can use Izanagi.

 

[Rot]

Zetsu is from Harishma..so ofcourse he has Senju dna, Harishama didn't create Zetsu but when Tobi showed Kabuto the 100K Zetsus a white/gooey Harishama was in the middle like a tree..you can probably easily find it as this was not too many chapters ago..right before the war started

Zetsu was probably created from Mokoton and Izangai, Mokoton being his white side which has been cloned 100K times and the black zetsu is the real zetsu/personality

Madara probably used Mokoton/Izangai to create black/white Zetsu like the sage created things with Izangai, and in one of them he placed his own cells/memory, which became Tobi, after all Edo Madara said he unlocked Rinnegan shortly before his death, if he had Senju cells from fight with first hokage and Rinnegan he could of used Izangai without being blinded, the So6P used Izangai(Yin;Rinnegan) to create from nothing then used Mokoton(Yang;Mokoton) to breathe life into the forms he created, he did this without losing his vision, meaning Rinnegan isn't limited to one use of Izangai