Board Thread:Versus Debates/@comment-27418151-20160521030355/@comment-5407586-20160522103000

Susanoo is a Mangekyō Sharingan jutsu, so anyone with the Mangekyō can master it (Indra, for example. He didn't have Six Paths Chakra, otherwise he'd have awakened the Rinnegan, though I believe that his MS didn't have the blindness side effect, because of him being Hagoromo's son). The problem is that MS usage causes blindness, especially with Susanoo, as seen in Sasuke's case: with the normal Mangekyō, one can reach at most the armoured form (without legs) before losing the eyesight. With the Eternal Mangekyō Sharingan one can go further by manifesting legs, and with enough mastery the Complete Body is reachable as long as the user has enough chakra to achieve it. Six Paths Chakra/Power (which brings forth the Rinnegan) is the ultimate shortcut for any technique, including Susanoo. Sasuke's Majestic Attire: Susanoo was his Complete Body form (the tengu nose is proof of that; after he was given Hagoromo's chakra, his Complete Body Susanoo changed to look more like Indra's).

Back to the topic… Tobirama "just" needs to mark Sasuke to win. The Second Hokage hasn't shown attacks fierce enough to pierce through Susanoo. If the Fourth Raikage could dodge Amaterasu, I'd believe that Tobirama could as well.