Well, it could be that Naruto discovers his divine heritage as the son of Jupiter. Maybe he has new powers like controlling lightning in a more god - like way. He could also have to face enemies from the Roman pantheon who are jealous of his unique status.
Well, it could start with Harry having some strange powers or dreams that lead him to discover his true father is Jupiter. Then he might have to navigate between the wizarding world and the realm of the Roman gods. Maybe he'd use some of Jupiter's powers in his battles against Voldemort.
One possible antagonist could be a jealous Roman god who doesn't want Naruto, as the son of Jupiter, to gain too much power. Maybe Pluto, who might see Naruto as a threat to his own domain in the afterlife.
It could work if Jupiter had some connection to the chakra system in Naruto's world. For instance, Jupiter's power could be the origin of a very powerful and rare type of chakra. Naruto, being his son in this fanfiction, would have a natural affinity for this special chakra, allowing him to perform feats that no other ninja could. This would change the power dynamics in the Naruto universe significantly.
One possible plot could be that Jupiter and Caine are in a relationship and the unexpected pregnancy throws their lives into chaos. They have to deal with the reactions of their friends and family, and also figure out how they are going to support a new life together.
Another possible new ability is the power of astral projection. Jupiter has a connection to the celestial realm. Naruto, as his son, could project his spirit into the astral plane. This would give him the ability to gather information from afar, spy on enemies, or even communicate with other celestial beings. It would add a whole new dimension to his ninja skills, making him not just a physical fighter but also a spiritual one.
In a 'naruto son of bellatrix fanfiction', perhaps Naruto has some of Bellatrix's wild and unpredictable nature. He could be on a journey to discover his true identity and how he came to be Bellatrix's son. This might lead him to explore the secrets of the wizarding world and his own ninja abilities in a new light.
Well, one possibility could be that Naruto inherits some of Gilgamesh's arrogance along with his power. Maybe he has a special ability to summon ancient Babylonian weapons. And he could use this in his battles in the Naruto world, like against the Akatsuki.
One possible plot could be that Naruto discovers his true heritage as the son of a princess from a hidden kingdom. He then has to deal with the politics and expectations of the royal family while still maintaining his ninja ways. Maybe he has to protect the kingdom from a new threat using his ninja skills.
In such a fanfiction, perhaps Naruto could be shunned by the village from the start. His 'devil' heritage might give him strange powers that he has to hide. He could struggle with self - identity, different from the Naruto in the original who is seen as a hero. Maybe he has to fight against the prejudice of the people who believe the devil's son can only bring destruction.
Well, it could be about Naruto having powers related to Hades on top of his ninja skills. Maybe he can control the dead or has some sort of underworld - like abilities that he uses in battles against the Akatsuki. He might also have to deal with the stigma of being the son of Hades in a world that doesn't understand such a thing.