Naruto: Itachi's Life Simulator

Before the Uchiha Clan Massacre, Itachi sensed that the Uchiha Clan was heading toward destruction. He went to Naka Shrine to examine the stone tablet, hoping to uncover more secrets. However, he suddenly passed out. When he woke, a [Life Simulator] System had appeared in his mind. It could take him to worlds with different systems of cultivation, where he could hone himself and change his life, making different choices. After Danzo stole Shisui's right eye, Shisui stood on the cliff above the Naka River and entrusted Itachi with his remaining left eye and his will before choosing to jump into the river and end his life. Itachi fully realized once again that the Konoha leadership, represented by Danzo, was utterly despicable. The choice Konoha had given him was now before him. Would he choose to let only Sasuke live? Or... choose to wipe out the entire Uchiha Clan?! Itachi acted without hesitation and chose to send Danzo to his grave!