Masked_Felix

It doesn't make sense if you look at it in a linear manner like that, no. Sandaime possessed abilities and fighting styles that let him prevail against Shodai and Nidaime at the same time. Orochimaru may have been able to handle them, too, with his damage regenerating techniques. Orochimaru's techniques and fighting style, however, were poorly attuned to taking on Itachi, and by extension, Madara. Shodai's wasn't, obviously. Not to mention that Sandaime had been brought up by Shodai and Nidaime, so he knew a few of their tricks.

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