Naruto: Nawaki was already dead, how could you bring him back to life?

Having transmigrated into the Naruto world, Chiba chooses to become a medical ninja in order to escape the war.
The unexpected result activated the "Saving Lives and Healing the Wounded" system, which allows users to obtain various powerful rewards by treating the wounded.
From then on, the ninja world gained another helpful kid.
Orochimaru: Nawaki's body is half burned; he's beyond saving.
Chiba: No, it can be saved.
[Ding! Congratulations, host, you have obtained the Senju bloodline (and Tsunade's)!]
Nawaki: Lord Sakumo's body is already cold, let's collect his body.
Chiba: No, it can be saved.
[Ding! Congratulations, host, you have received a physical enhancement (can open six gates)!]
With the blood moon hanging in the sky, Madara was left with only half a body, about to die from exhaustion of chakra.
Everyone: Great! Uchiha Madara is finally...
Chiba: No, it can be saved.
Everyone was shocked: "No, you have two arms, why did you save him?!"
[Ding! Congratulations, host, you have obtained the Rinnegan and the power of the Six Paths...]
……
After receiving countless rewards, Chiba suddenly discovered:
Those self-proclaimed gods of the Otsutsuki clan seem unable to withstand even a single attack from him, a medical ninja.