Undoubtedly, Black Zetsu was never of one mind with anyone. Whether Madara Uchiha, Obito, or Nagato, these were all objects he utilized!
And his goal was always only one, which was to resurrect his mother, Kaguya Otsutsuki.
However, to resurrect Kaguya Otsutsuki, a 'vessel' capable of containing Kaguya Otsutsuki's will must be created.
In the Ninja World, to create such a 'vessel', one could only use Kaguya Otsutsuki's bloodline descendants to resurrect the Ten-Tails, complete the 'Infinite Tsukuyomi' plan, concentrate all chakra scattered in the Ninja World onto one person, elevate this person to 'Six Paths Level', and then resurrect Kaguya Otsutsuki using this person's body.
In the original timeline, Madara Uchiha perfectly met Black Zetsu's requirements.
Thus, Black Zetsu disguised himself as the product of Madara Uchiha's will, assisting Madara Uchiha all the way. And after Madara Uchiha became the Ten-Tails Jinchuriki and activated 'Infinite Tsukuyomi', he sneak-attacked Madara. Using Madara, this 'vessel' who just advanced to 'Six Paths Level' and couldn't resist Kaguya Otsutsuki's will yet, he successfully resurrected Kaguya Otsutsuki!
In the current timeline, Black Zetsu was originally advancing according to plan. However, Shinji's emergence disrupted his plan, not only snatching away the Ten-Tails but also snatching away Madara Uchiha's pair of Rinnegan deposited on Nagato, forcing him to choose another target.
Logically, as Kaguya Otsutsuki's bloodline descendant, Shinji was undoubtedly the best target. It's just he found Shinji very cautious, having no chance to approach at all. So he could only settle for the second best, targeting Isshiki Otsutsuki suppressed by Shinji.
Before acting, he wasn't sure if he could restrain Isshiki Otsutsuki either.
After all, Isshiki Otsutsuki was a genuine Otsutsuki, not a newcomer like Madara Uchiha in the original timeline who just advanced to 'Six Paths Level' with the help of the 'Ten-Tails'.
But Shinji's action this time helped him, severely weakening Isshiki Otsutsuki's power, which allowed him to successfully restrain Isshiki Otsutsuki.
"D-damn it!"
Isshiki Otsutsuki reacted at this moment too, the expression on his face twisted due to extreme anger.
He never expected to fall into Kaguya Otsutsuki's hands again, and this time it was even under the circumstance that Kaguya Otsutsuki was sealed.
How ironic this was!
Anger and unwillingness made Isshiki Otsutsuki try to resist Black Zetsu's invasion. He used his fingers with difficulty, bending slightly.
Swish swish swish...
In an instant, several black rods appeared out of thin air, hitting Black Zetsu's body.
"Useless!"
Black Zetsu grinned, face full of pride.
His body was like flowing liquid. The black rods hitting him passed through his body quickly, falling to the ground, making 'ding ding clank clank' sounds.
Isshiki Otsutsuki's resistance had absolutely no effect, while Black Zetsu's infection deepened step by step. More and more ink color attached to Isshiki Otsutsuki's body, already approaching half of the body surface area.
Eida frowned slightly: "Such strong chakra!"
Daemon clapped his hands laughing: "Didn't expect Isshiki Otsutsuki to have such an embarrassed moment, really interesting!"
Obito hiding in the ruins showed a horrified face.
He knew Black Zetsu had been hiding secrets, just didn't expect the secret hidden on Black Zetsu was so deep. If not for Isshiki Otsutsuki exclaiming 'Kaguya Otsutsuki' just now, he would probably still be kept in the dark until now.
Subsequently, he instantly understood a lot, feeling somewhat lost in soul.
He thought he was using Nagato and Madara Uchiha, but in reality, he, Nagato, and even Madara Uchiha were all used by Black Zetsu.
The 'Eye of the Moon Plan' they had been dedicated to completing was just a scam by Black Zetsu to resurrect Kaguya Otsutsuki.
Just think about it, if even a genuine Otsutsuki like Isshiki Otsutsuki could be controlled by Black Zetsu, then how could he or Madara Uchiha, who successfully resurrected the Ten-Tails and activated 'Eye of the Moon', possibly withstand Black Zetsu's plot!
Thinking of this, Obito looked fiercely at 'A' in the air.
Right now, only 'A' could stop all this from happening. Otherwise, once Black Zetsu succeeded, the weak Isshiki Otsutsuki would be possessed by Kaguya Otsutsuki.
By then, the entire Ninja World would tremble under the fear of Kaguya Otsutsuki, the 'Progenitor of Chakra'!
However, contrary to Obito's expectation, 'A' in the air took no action, just quietly watching Black Zetsu erode Isshiki Otsutsuki's body bit by bit.
Obito exclaimed: "Isn't he worried about Kaguya Otsutsuki resurrecting at all?"
Sharing the same doubt as Obito were Amado and Orochimaru in the surveillance room.
At this time, only one screen on the entire wall of screens in the surveillance room was still working. Through this screen, Amado and Orochimaru learned the situation on the spot.
Amado exclaimed: "Must stop him!"
"I know!"
While responding, Orochimaru warned Shinji present through 'Jikibi'.
In the air.
Shinji was still watching quietly.
Previously he had always wondered how Kaguya Otsutsuki created Black Zetsu out of thin air. Now after experiencing the development of 'Karma', he discovered that Black Zetsu created by Kaguya Otsutsuki, to some extent, was also a kind of 'Karma', a living 'Karma' with self-awareness.
And this was probably why Black Zetsu could subdue Isshiki Otsutsuki.
Because according to chakra level, even if Isshiki Otsutsuki recovered to peak, he was just 'Six Paths Level'. Compared to Kaguya Otsutsuki who consumed the Chakra Fruit and successfully advanced to 'Kekkei Mōra', he was still obviously inferior.
So once Isshiki Otsutsuki fell into weakness, Black Zetsu, this alternative 'Karma' created by Kaguya Otsutsuki, had an opportunity to exploit.
Black Zetsu's gaze also fell on Shinji in the air at this time.
Although not understanding why Shinji watched helplessly as he corroded Isshiki Otsutsuki, Shinji standing by was obviously the best result for him.
But he didn't thank Shinji, instead thinking in his heart: "All chakra in the Ninja World belongs to mother. After mother resurrects, she will reclaim all chakra bit by bit! Hehe, 'A', just wait, I will watch mother drain all your chakra without a trace left!"
Boom...
Just as Black Zetsu was immersed in the beautiful fantasy of Kaguya Otsutsuki sweeping the Ninja World after resurrection, accompanied by a loud noise, a dazzling golden light suddenly illuminated the entire town ruins, and even the entire world!
Black Zetsu didn't even have time to react to what happened, his consciousness came to an abrupt end, and his whole person dissipated under the dazzling golden light!
Shinji in the air curled the corners of his mouth slightly: "Isshiki, sure enough you couldn't help using it!"