Injecting the Serum

Before Tsunade could react, Orochimaru reached out and yanked up her sleeve, then drove the needle straight into her arm.

At the same time, he explained, "I've tested the 'Hashirama Number One' serum many times. There definitely won't be any problems."

Although Tsunade still harbored a trace of doubt after hearing Orochimaru's words, his utter confidence made her set aside her worries for the moment.

However, when she heard what Orochimaru said next, Tsunade was left speechless and could not help rolling her eyes.

"If something truly goes wrong beyond my calculations, the simplest solution is to kill you and bring you back to life."

Orochimaru's words remained cold and merciless, as though human lives were nothing more than pieces he could manipulate at will.

Though dissatisfied with Orochimaru's extreme attitude, Tsunade knew very well that he never lied about such matters.

After all, he had always been exceptionally rigorous and serious when it came to scientific research and experiments.

At that moment, Orochimaru swiftly pushed the syringe's contents into Tsunade's body, and the entire process took barely more than ten seconds.

Without pausing, he immediately picked up another vial of 'Hashirama Number One.'

He drove it directly into Nawaki's arm and completed the injection at astonishing speed.

As the serum gradually entered her body, Tsunade felt nothing unusual during the first half-minute.

But half a minute later, she suddenly felt a wave of heat well up from within, and her body temperature began rising rapidly.

As the most skilled medical ninja, Tsunade keenly sensed the changes in her body.

After assessing the situation, she was shocked to discover that her body temperature had risen by at least three degrees!

That temperature was clearly within the range of a high fever.

Not only that, Tsunade experienced several other uncomfortable symptoms