Immortality Starts with Naruto

Ren Yasaka, who traveled back in time to the Warring States Period of Naruto, succeeded in becoming a retainer of the Senju family by virtue of his ability to survive no matter what, and worked with the two brothers Hashirama and Tobirama to calm down the troubled times. Then... "I said, do you really want to inject this thing into your body?" In a secret laboratory somewhere in Konoha 1, even Senju Tobirama, who is famous for his research on forbidden arts, did not dare to look at the thing in Lian's hand. "Don't worry, you won't die~~" The test tube in Lian's hand contained all the blood ninja cell samples he could collect during the Warring States Period, including but not limited to Byakugan, Sharingan and Wood Release. "Fei Lao Er, please!" Lian, who was holding the test tube, gave a thumbs up to his injured friend, showing a bright smile that was no different from Metkai's. "Okay, no matter what you choose, you won't die." "I'm afraid I will fall asleep for a while, and I will take you to fly when I wake up!" Tobirama stabbed Lian down with a needle and quickly lost consciousness. When he woke up again... "What? It's been 50 years since Konoha?!" "Okay, Naruto hasn't been born yet, so there's still time... Wait a minute? What do you mean I have to fuse all the blood successors injected into my body?"