Board Thread:Theories and Speculation/@comment-26636534-20150710195521/@comment-734582-20150711193439

Chaosattractor wrote: You don't need extensive knowledge to form a strategy against them. You don't even need to know what they are. All you need is the observation that hey, this shield is repelling everything and this sword is sealing away shit (and any half-intelligent person would already be using decoys to figure out their opponent). Itachi pulled out Susanoo as the last line of defense. I'm not sure what kind of ninja you'd need to be to get to that point. But Shippuden pretty much shows that you'd need to be a Sennin to get that far.