i found an interesting convo (debate) happening in this tread, so i followed it pretty far back.
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i agree with everything in this reply by edge back to yetanotheruser (YAU). good job edge. as he did, i will also reply to your questions YAU.
Did he have large impact on humans? No.
depends on what you refer to as a large impact. the sage's son didnt have a big impact either (as far as we know).
Lets see.. He was pulling the strings all the time and manipulated many people, yes, he did have large impact.
Does he have an evil character? No.
as stated by edge, we dont have enough info to go one way or another. regardless, what does this have to do with tobi? for all we know, tobi isnt doing anything "evil" (looking at it from his point of view), he is just stopping people from having dreams in order to achieve peace. all he needs is 10 individuals to "save" the world - in his eyes.
Yes. I already mentioned before that this personality rather fits to the elder son than Izuna. He elder son believed that peace could be achieved through power and strength. Tobi also does thinks this way.
Was his dead confirmed? Yes.
edge, YAU has a point here...
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(cant find the manga page at the moment). so, yes his death was shown...but im not sure it confirms anything. this was the only thing holding me back thinking tobi = izuna. but with the edo tensei (and the ability to release it as shown by madara in chapter 592), its quite possible izuna was revived by madara himself before he died. this also gives a reason to how madara was able to counter edo-tensei himself. maybe thats why tobi never worried too much about kabuto releasing madara against tobi because he knew madara would be able to free himself.
If Madara says he is dead, he is dead. There is nothing to discuss about.
Is he somewhat interesting? No.
why not? as edge said, he was able to fight on par with madara for years. what dont you like about him vs the sage's son? we have have limited to no information on either of them. so you cant dislike someone without knowing them - unless you are a person who judges people based on looks.
Let's see... the greatest mystery in this manga is just a random Uchiha whose only job was to give his eyes to his brother. Nice story writing... I am impressed...
Was it worth waiting years just for Izuna? No.
depends on the story. it doesnt really matter who it turns out to be as long as they have a reasonable explanation of how things worked out.
See previous point
Does he fit into the plot? No.
why not? for now, anyone can fit the story and no one can. again, it depends on the back story.
Okay, he might actually fit. But I doubt it's him.
Does he fit being the final villain? No.
i doubt the final villain will be tobi. imo, it will end up being madara. or worse, like in some manga, it could a super combo villain - tobi + madara + oro. they transform into one being called:
madorobi. yes its a little crazy, but in many anime/manga, we see heros or villains combine to make a superhero or supervillain.
(btw, im still hoping sasuke and naruto fight together xD)
He is the final villain. I am sure he is.
Does he have something special that differs him from other people? No.
edge said it best, please read below. (minus the sarcasm).
Was his
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Tobi? No. (Unless you can change names...)
this is probably the worst question in this group. it makes you look desperate lol. this is probably the least convincing arguments that tobi cant be izuna - and if it turns out to be true (which i hope it doesnt) - it even proves that tobi cant be the son of the sage.
No. This is actually a good question.
Could he ever achieve this amount of skill and knowledge like Tobi got? No.
in naruto wiki, it says izuna/madara existed about 80yrs ago. (i didnt feel like doing the math to guess their age). so i would say that it is enough time for izuna to gain knowledge and skill. first off, he already has MS and possibly had the rinnegan. if kakashi is able to copy a 1000+ jutsus with just a normal sharingan and be one of the smartest shinobi's in konoha (in his 30 years), then im sure izuna can also do the same in twice that long.
So? How could he know about SO6P, his sons, the bijuus etc. etc. ? He DOES lack knowledge, also skill. Tobi seems to have great mastery over Sharingan. Controlling Kyuubi using standard Sharingan is imho not something that Izuna could be able to do.
Would anyone ever care who the hell Izuna is? No, except Madara.
finally, you proved everything here yourself.

the main reason tobi exists - to me at least - was to revive madara. yes the moon's eye plan is there, but madara and tobi had planned this in the past. everytime tobi referred to the moon's eye plan, he called it something along the lines of: "MY PLAN...UCHIHA MADARA'S PLAN". so we all should care if madara cared about tobi/izuna.
Oh... this is all. Just reviving Madara. So Tobi controlled that many people, founded Akatuski, exterminated the Uchiha clan, etc. etc.. just to revive his brother?
And now you stop denying facts. Izuna is just a random, unimportant Uchiha that Kishi threw track to confuse his readers. Same applies to Kagami. The most logical person outta there is definitely the elder son.
what are facts? everyone can get facts to "prove" their point is correct. based on everything we know, it could still be anyone. i dont know why people say its kagami other than his relationship with danzou - i guess they were on the same team in the past? and to add what you said, the name "TOBI" could also be something kishi threw in the story to confuse readers between tobi and obito as you might be thinking...lol.
Believe it or not. I am convinced it is the elder son.
ok, but have you shown any facts? maybe i havent gone far enough back to read your posts and your proof. if you can link it to me, then i'd love to read it. but from what ive read in this post, you are just denying why it cant be izuna based on one fact (the death picture) and a whole lot of speculation.
I did write some more stuff why I think its him
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