At different levels of strength and from different perspectives, one's attitude toward these experimental subjects would be worlds apart. This was exactly the case for Shinji and Amado.
What Amado saw as a massive threat, Shinji saw as a rich mineral vein where the benefits outweighed the risks—a treasure trove that could be continuously mined and researched!
If time allowed, Shinji would actually prefer Amado's conservative strategy, but the current situation no longer permitted him to be cautious.
As for purifying the chakra of these test subjects and removing the residual will of Otsutsuki Shibai, Shinji had attempted it privately. He discovered that in the entire shinobi world, only he, as a Kekkei Mora, possessed this ability. Others, even powerhouses like Toneri, Karin, Hikari, or Shion, could not avoid being influenced by Shibai's lingering will within that chakra.
Therefore, if he wanted to use Hikari's Yachihoko to control this rapidly expanding group of subjects, finding a way to efficiently purify the chakra was a challenge Shinji had to face.
The Land of Hot Springs.
At the Research Institute, multiple groups worked in parallel, pushing research forward at a blistering pace every day. During this past month, Obito, hiding in the dark underground cavern in the Land of Hot Springs, had not been idle either.
Armed with the peak Eternal Mangekyo Sharingan that Shinji had deliberately left for him, and utilizing the White Zetsu cells infused with Sasuke's chakra provided by the Institute, he finally succeeded in awakening his own Rinnegan!
Obito tore off the bandages on his face and slowly opened his eyes.
Staring at the pale purple Rinnegan in Obito's sockets, White Zetsu said excitedly, "I knew you could do it!"
White Zetsu was genuinely happy.
However, he wasn't happy for Obito; he was happy for Shinji. Shinji's judgment had been correct—Obito truly possessed the aptitude to reach for the Rinnegan!
On the stone bed, after adjusting for a moment, Obito quickly grew accustomed to the dim light of the cavern and saw his surroundings clearly. A smirk tugged at the corner of his mouth. "So this is the Rinnegan..."
With a thought, Obito reached toward the empty air in the distance. A jar quickly flew toward him and landed perfectly in his hand.
"Bansho Ten'in!"
Obito's smile widened.
He was no stranger to the Rinnegan, but experiencing its dojutsu personally for the first time filled him with a thrill he couldn't hide!
Suddenly, he frowned slightly. "A pity. Now that I've awakened the Rinnegan, I can't activate Kamui."
A standard pale purple Rinnegan could not simultaneously utilize the dojutsu of the Eternal Mangekyo. Only by evolving it into a Six-Tomoe Rinnegan could the techniques from the Mangekyo period be used once more!
White Zetsu stepped forward. "I'm ready whenever you are!"
The plan to seize the small Ten-Tails required the help of Kamui. Thus, while Obito was attempting to awaken the Rinnegan, Shinji had used White Zetsu to suggest a method: before Obito reached for the new realm, he would store a massive amount of his Sharingan's pupil power within White Zetsu, then have White Zetsu feed it back to him to stimulate the new Rinnegan into evolving.
Theoretically, this plan shouldn't have worked.
Shinji had succeeded before because of Hikari's domineering Yachihoko. If Obito relied solely on the pupil power stored in White Zetsu, the success rate was essentially zero.
Of course, Shinji would not let Obito fail!
He would use White Zetsu's body as a relay station to remotely activate Yachihoko from a thousand miles away!
Obito, having just gained the Rinnegan, still had doubts. "Can your plan really work?"
White Zetsu replied, "I heard the researchers chatting about it. It should work; besides, we have nothing to lose by trying!"
Obito nodded.
The researchers' ability to evolve his Mangekyo into the Eternal Mangekyo was proof enough of their skill. As White Zetsu said, it was worth a try.
Soon, the two were ready. White Zetsu placed a hand on Obito and said, "Prepare yourself. I'm giving your pupil power back to you!"
"Bring it!" Obito's gaze sharpened.
Before he finished speaking, a powerful surge of chakra erupted from White Zetsu and slammed into Obito's body.
"So... so strong!" Obito was shocked.
Having only just gained the Rinnegan, his understanding of chakra was not yet profound. He couldn't see through the fact that this was actually a chakra impact launched by Shinji; he couldn't even properly analyze the chakra White Zetsu was sending him. He could only endure it passively.
A long time later, with a loud boom, Obito was sent flying by the massive volume of chakra, crashing hard into the cavern wall.
Though the fall was painful, Obito didn't care. He stood up and looked at his hands, finding his body in an intangible state. He cried out in surprise, "It's back! My Kamui is back!"
The restoration of his Mangekyo techniques was proof that he had successfully awakened the Six-Tomoe Rinnegan.
White Zetsu slumped to the side, saying weakly, "You... you succeeded again!"
Obito glanced at White Zetsu and noticed his body had shriveled significantly, as if his chakra had been completely drained. Obito walked to his side. "Are you alright?"
White Zetsu smiled. "I'm fine. I'll recover soon."
"Good." Obito nodded.
If he had any lingering doubts about White Zetsu's loyalty, they vanished after seeing him risk everything to help him awaken his eyes.
Obito then felt the changes in his body.
If this were a subordinate Shinji actually intended to cultivate, he would have let them stabilize and adapt to the Rinnegan before attempting the Six-Tomoe evolution. But Obito was merely a test subject for the "Sacrifice Plan." Shinji didn't have the luxury of time to train him slowly, so he forced the evolution. Fortunately, Shinji's current strength was enough to ensure the success of the impact.
Furthermore, accelerating the progress helped confuse Obito, causing him to overlook certain details and preventing the plan from being exposed prematurely.
Just as Shinji expected, the rapid leap in strength reignited Obito's ambition!
"Uchiha Shinji, I will make you pay the price for looking down on me!" After making his decision, Obito turned to White Zetsu. "I need intelligence on the Ten-Tails."
White Zetsu smiled. "Rest assured, the Ten-Tails is one of their research materials; it must be at the Institute! I have many clones there. If we're careful, we should be able to find its location!"