Board Thread:Versus Debates/@comment-26998824-20151210004253/@comment-27418151-20151222212958

Ninja Of War wrote: Tobirama wouldn't be helpless against Itachi's genjutsu. Due to growing up in the Warring states period and fighting against the Uchiha clan for years, he most certainly in not going to be surprised at an Uchiha with mastery in genjutsu. Tobirama has most likely trained himself to at least be able to avoid sharingan genjutsu and even be resistant to it. The same goes for Tsukuyomi.

Being mentioned as the fastest shinobi alive in his lifetime is also significant. This puts Tobirama above Itachi in terms of speed and being a Senju puts Tobirama above Itachi in terms of strength and chakra. As for ability and intelligence, Tobirama has been described as a genius from a young age, is one of very few shinobi able to use all main nature releases, developed his own powerful ninjutsu that other shinobi have learned from and made their own and finally has amazing analytical and perceptive abilities.

If all this is taken into account, Itachi seems like the one at a disadvantage. so far I know Tsukuyome can only be countered by another sharingan user,but tobirana probably wouldn't fall on it.