Though the Seven Ninja Swordsmen of the Mist were powerful, they were nothing before the truly strong. Take the Five Kage whom Madara Uchiha had defeated, for instance. Ōnoki and the Fourth Raikage might well have been able to take on all seven swordsmen alone.
Yet Madara Uchiha, revived through Impure World Reincarnation, had fought all Five Kage by himself. It even felt as though they might not have stood a chance against him with ten times their number.
To put it bluntly, apart from Hashirama Senju, every Kage who had ever lived before the Fourth Shinobi World War could have joined forces and still been no match for Madara Uchiha.
As for Hashirama Senju, even he would have lost to Madara Uchiha in a one-on-one fight at that point. But with so many Kage supporting Hashirama Senju, Madara Uchiha would probably have been in trouble.
An overwhelming pressure radiated from Uchiha Yi, something the other members of the Seven Ninja Swordsmen of the Mist had never expected at first. After all, Uchiha Yi was only a ten-year-old brat. Even if he would turn eleven in a few months, an eleven-year-old was still a kid who hadn't even grown hair down there. How could he possibly threaten them?
Even Madara Uchiha and Hashirama Senju had been nowhere near this strong at his age.
Now, even these remorseless killers began to panic. Had they known Uchiha Yi was this powerful, they would never have provoked him.
And that was the end of it. Uchiha Yi pressed his advantage, continuing his assault on the Seven Ninja Swordsmen of the Mist and taking their lives in short order.
Once it was all over, Uchiha Yi took out a Storage Scroll and sealed the swordsmen's bodies inside. These were elite shinobi from Kirigakure, and