Legend of Kuro Uchiha

Kuro Uchiha, formerly known as Kuro Valar in Earth was a top tier assasin that was nicknamed "The Death God" was hunted by every faction in the underworld and was betrayed by the only person who treated him as a person. Before he was killed, he was suddenly transported into a world that is similar to the  "Naruto World" with chakra and a mix of magic and martial arts.