In some fanfiction, Naruto might be depicted as a cold killer, but this goes against his canonical character. In the original Naruto series, he is a warm - hearted and determined ninja who values friendship and peace. However, in the realm of fanfiction, authors can take creative liberties and present a very different version of him.
A possible reason could be a tragic backstory that twists his personality. For example, if he witnessed something extremely traumatic, like the death of all his friends at a young age due to the actions of a certain group, it might turn him into a cold killer seeking revenge in fanfiction.
No. Naruto is known for his warm - hearted and determined nature in the original series. Fanfiction that portrays him as a cold - blooded killer goes against the fundamental character traits that the majority of fans love about him.
Sasuke could potentially be the main character in a 'naruto cold killer' fanfic. He already has that brooding and somewhat cold personality. In this fanfiction, he could take his thirst for revenge to an extreme level and become a cold - blooded killer, hunting down those he believes are responsible for his clan's massacre. This would be a very different take on his character compared to the original Naruto story.
Well, it might not be as popular as some other positive or heroic fanfiction in the Naruto fandom. Many Naruto fans are drawn to the themes of friendship, growth, and heroism that are prominent in the original series. However, there could be a niche group who are interested in exploring the darker side of the Naruto universe through 'cold blooded killer' fanfiction.
I don't think so. Naruto is known for his strong sense of justice, his loyalty to his friends, and his will to protect his village. These qualities are completely opposite to what a cold - hearted killer represents. Fanfictions that deviate too much from the original character traits may not be as popular among the mainstream Naruto fanbase.
One possibility could be a great tragedy that befalls him. For example, if all his friends were brutally killed in front of him by an enemy he couldn't defeat at that time. This might shatter his belief in the goodness of the world and drive him to become cold - blooded in order to seek revenge. He would start to see killing as the only way to get justice.
One idea could be that the cold killer is a rogue ninja who was once a part of a secret Anbu - like organization in the Naruto world. They have a tragic past that made them turn cold - hearted. For example, they witnessed their entire clan being massacred by a powerful enemy. Another plot could involve the cold killer being hired to assassinate a major Naruto character, but during the mission, they start to question their own motives and actions when they learn more about the target. Maybe they find out that the target is not as bad as they initially thought.
One potential enemy could be Danzo. In the original series, Danzo had many shady dealings. If Naruto turns cold - hearted, he might see Danzo as a threat to Konoha's true peace and go after him. Another enemy could be Kabuto. After his experiments and all the chaos he caused, a cold - hearted Naruto might not tolerate his existence. Also, there are the Akatsuki members. Naruto could target them in a more ruthless way, especially Pain, who once attacked Konoha and caused a great deal of destruction.
One common plot element could be a character, perhaps Naruto himself, being corrupted or forced into a life of killing. Another might be the exploration of the darker side of the ninja world, like the underbelly of the Hidden Villages. There could also be a focus on revenge as a motivation for the cold - blooded killing.