Naruto World with a Simulation System

Synopsis:

An old assassin has transmigrated into the world of Naruto.

He became none other than Naruto himself.

Is it transmigration or rebirth?

The sleeping Naruto woke up and thought for a few minutes…..

Slowly the light returned to his eyes.

Tring

“The Assassin system is activated”

System: host I will make you the strongest assassin in the world.

Protagonist: What are you talking about I am already a retired old assassin and the greatest assassin of my previous world.

System: host I will make you the strongest assassin in this world using that chakra and its abilities.

Protagonist: well that is new then let’s get started…..