Besides Naruto, it could be that the main characters include some of the gods from God of War 4. For example, Odin. He could be intrigued by Naruto's powers and try to either use him or destroy him. And Naruto would have to use his wits and strength to deal with this powerful and conniving god, making for a great power struggle in the fanfiction.
Naruto and Atreus could be the main characters. Naruto, with his exuberant and positive personality, could contrast well with Atreus' more somber and in - process - of - growing - up nature. They could learn from each other and face challenges together, like dealing with the various mythical creatures in the God of War 4 world.
Orochimaru might also be a main antagonist. He is always after power and knowledge. In the context of the 4th war with a god involved, he could see the god as a source of ultimate power. So he might try to manipulate the situation to either steal the god's power or use Naruto to get to the god's power. He could be secretly working behind the scenes, causing trouble for Naruto and his allies.
Sakura could be one of the main female characters. She has always had a connection with Naruto, and after the war, her feelings might have changed or deepened. Hinata is also a likely candidate as she has long - admired Naruto. And perhaps some new characters from other villages could be introduced as well.
Sakura could be a main character. She might be the one who helps Naruto deal with his emotional and physical wounds after the war. She could also be struggling with her own feelings towards Naruto now that he's back.
It could be the traditional God of War villains like the gods who oppose Izuku. Maybe Ares, if he's still around in the fanfiction's version of the God of War world, would see Izuku as a threat and try to stop him.
There could be an ancient evil force that awakens because of Luffy's new powers. This force was once sealed away but now wants to destroy Luffy and everything he stands for, seeing him as a disruption to the balance it once knew.
Naruto and Sasuke would be very likely to interact. If Naruto has God of War powers, Sasuke might be curious or even envious. They could have a fight or a conversation about these new powers. Another pair could be Naruto and Kakashi. Kakashi would surely be interested in Naruto's new abilities and how they could be used for the village.
The main characters in 'prince of war naruto fanfiction' would most likely start with Naruto, the hero of the original series. The prince character is a given as it's in the title. Additionally, characters like Kakashi could be important as he is a mentor - like figure. There could also be antagonists who are trying to use the war for their own gain, and they would also be main characters in terms of driving the plot. Maybe there are some original characters created specifically for this fanfiction that are also key players in the story, like a powerful general on the prince's side or a rogue ninja working against the prince's cause.
It's likely that Naruto himself would be a main character, as the fanfiction is related to the Naruto universe. He might be involved in the battles and the acquisition of spoils.
Obviously Naruto would be one of the main characters. Since it's based on Naruto, he would be central to the story even in this dog - of - war scenario.
The main character is Naruto. But we may also see more of Naruto's family members, such as his father in flashbacks. Allies from other villages that join Naruto in the fight during the war could also be main characters. And of course, the villains who are driving the war forward are also important characters in this fanfiction.