Black Zetsu had mainly been able to bring Jyuuzou Biwa into Akatsuki because Jyuuzou Biwa was the sort of person with enormous ambition and aspirations. Otherwise, no matter how exceptional Black Zetsu's ability to manipulate people's hearts was, it would not have been easy for him to recruit Jyuuzou Biwa so casually.
It was obvious enough just by looking at the Seven Ninja Swordsmen of the Mist. Only one of them had joined Akatsuki. The others had shown no reaction at all; they might not even have known Akatsuki existed, or perhaps Black Zetsu had never contacted them.
With that, Akatsuki's core membership had reached six people.
Nagato, Konan, Black Zetsu, Sasori, Kakuzu, and Jyuuzou Biwa.
With six suitable members in place, Black Zetsu's plans gradually began to unfold. For him, the time had come to test Hiko.
The major ninja villages were still working hard to investigate everything about the Akatsuki Organization. Ōnoki relentlessly sent Iwagakure ninja to attack Konoha, but Hiko did not take it too seriously, handing more of the matter over to Hatake Sakumo.
He even used the excuse that he was training Hatake Sakumo, leaving him unable to refuse. He could only grit his teeth and take it on. In truth, Hatake Sakumo was indeed formidable. Even an old fox like Ōnoki found it difficult to gain any advantage against him.
In the original story, Hatake Sakumo's reputation had not been as resounding as that of the Sannin. The biggest reason was that he had died too early, leaving behind too few glorious achievements. On top of that, he had chosen to take his own life after a mission failure, which had caused a major negative impact. Naturally, no one in the village would go out of their way to publicize him, causing Hatake Sakumo