Kazemori Masaki knew Black Zetsu would certainly take part in the coming battle. He only needed to confirm where he would appear. Most likely, Black Zetsu had no idea that Masaki knew his identity, so his guard would be down. He would assume that even if he lost, all he had to do was play dead.
Masaki only needed to make arrangements with Kagami Uchiha. When the time came, one thrust of the Totsuka Blade would make Black Zetsu realize that things were not as simple as he had imagined. By then, it would already be too late for him.
"This fellow is troublesome. We need to keep a close eye on him," Kazemori Masaki said. "Kagami will handle him. He has a way to deal with him."
Everyone instinctively assumed that Kagami Uchiha's Mangekyō Sharingan would serve that purpose. In a sense, they were right. The Totsuka Blade, after all, also depended on the Mangekyō Sharingan to exist.
Kagami Uchiha nodded slightly. He understood what Kazemori Masaki meant. Since Masaki suspected that this fellow was the mastermind, he naturally had to test that suspicion. Judging by the intelligence on Black Zetsu, he was indeed deeply strange. Whether he was the mastermind or not, sending Kagami to deal with him was a sound approach.
It would take no more than a single strike from the Totsuka Blade. Since awakening his Mangekyō Sharingan, Kagami Uchiha had used it only a few times toward the end of the war and while subduing the Totsuka Blade. He had never used it since. His Mangekyō Sharingan was still in fairly good condition, so using it once to deal with Black Zetsu would be no trouble.
Ever since learning that an ordinary Mangekyō Sharingan would eventually lose its sight, Kagami Uchiha had exercised great restraint