Konoha.
Konoha Hospital's intensive recovery ward.
An energetic yet gaunt old man slowly steadied himself with the support of a medical ninja beside him.
The Third Hokage, Mitokado Homura, Utatane Koharu, and Nara Luhe all stared intently at his left foot.
His left foot was pale yellowish-white and looked exceptionally young, starkly different from the bronze skin on the rest of his body.
He crouched down and pressed the skin on his leg. It was warm and responsive to touch.
Then he planted his foot firmly on the ground, yet did not feel the slightest pain.
Though it was not as strong as his right foot, it was completely healthy.
The next moment, he walked over to the wall and used Chakra to stick his leg to it.
Then he dropped back down.
"No problem, Lord Hokage. Absolutely no problem!"
The old man was named Maruboshi Kosuke, known as the "Perpetual Genin."
After a mistake on an early mission had led to his companion's death, he swore to the Second Hokage, Senju Tobirama, that he would remain a Genin for life.
The Second Hokage taught him Water Release ninjutsu, and though the Third had once wanted to promote him to Jōnin, he had refused.
During the Third Shinobi World War, his left leg had been crippled while carrying out a mission with the Fourth Hokage.
That was why he had become an important candidate for this experiment.
"My leg is completely healed! The Chakra flow is a little slow, and it still feels somewhat weak, but with some training, it should recover."
"Lord Orochimaru's technique is truly incredible."
Hearing this, even someone as composed as the Third Hokage could not hide his delight.
"Hahaha, good, good, good! Kosuke, from now on, cooperate with the medical ninja and focus on rehabilitation."