As the son of Atlas in fanfiction, Percy could gain the power of elemental control over earth and sky elements. He might be able to call upon the strength of the mountains (related to Atlas's role in supporting the sky) to create barriers or cause earthquakes. In terms of sky - related powers, he could have the ability to change the color and appearance of the sky, perhaps as a form of camouflage or to send signals. He may also possess a form of telekinesis that is specifically attuned to celestial objects, allowing him to move stars, comets, or even planets on a small scale.
Well, if Percy is the son of Atlas, he might possess the power of spatial manipulation. Since Atlas was associated with holding up the sky, which is a vast expanse of space, Percy could potentially have the ability to bend or shift space around him. He could also have the power of air manipulation, as the sky is related to the air. This could include creating powerful gusts of wind or even being able to breathe in places without air. Additionally, he might have the power to create portals to different celestial locations, given Atlas's connection to the heavens.
He could have the power of enhanced strength related to carrying the weight of the sky, like Atlas did. Maybe he could also have some form of gravitational control, being able to manipulate objects' weight or even make them float. Another power might be the ability to see and interact with celestial bodies in a more direct way, like being able to draw energy from the stars.
Well, as Zelena's son, Harry could have her power over fire, which she sometimes uses in her magic. He could also have the ability to communicate with animals, as Zelena has a certain connection to the natural world. Another power he might possess is the power of teleportation. Zelena is quite mobile in the story, and Harry could inherit this trait, allowing him to move quickly from one place to another. But it's also possible that his powers are a combination of Zelena's and some unknown latent magic within him, which could make his powers unique and unpredictable.
He could inherit Naruto's chakra - rich nature. So, he might have a large reserve of chakra like his father. Also, since Naruto has the Nine - Tails' chakra, Minato might have some sort of unique connection to it as well, perhaps being able to access a small portion of its power in a different way than Naruto does. And of course, he could inherit some of Naruto's signature jutsu like the Rasengan, but with his own twist.
Maybe he has the power of a different tailed beast. Since Naruto has a connection with the Nine - Tailed Fox, his son could be linked to another tailed beast, which would give him a whole new set of powers and challenges. He'd have to learn to control this power, just like Naruto did with the Nine - Tailed Fox's chakra.
It's possible that he has the power to summon creatures related to Amaterasu. Maybe some sort of fire - spirit or a mythical beast associated with the goddess. And from Naruto, he could inherit the ability to enter Sage Mode, which would further enhance his combat capabilities when combined with his fire - based powers.
He could have the power of lightning, like Zeus. Maybe he can control it better than other demigods. Also, he might have enhanced strength and speed, similar to Zeus's own capabilities.
Another ability could be dark energy projection. Naruto could project bolts of dark energy from his hands or body. This energy could be used to blast away enemies or even to corrupt other things it touches, like sealing jutsu or barriers. It would be a very different and more sinister form of attack compared to his normal Rasengan.
The theme of family also plays a role. Percy has a complex relationship with Atlas as his father. Some fanfictions explore how this new family connection impacts his view of family, especially compared to his relationship with his mother and his friends who were like family. There could be moments where Percy has to choose between his loyalty to his new - found father and his old relationships, creating a lot of internal conflict and drama within the story.
Percy might embark on an adventure to find other lost Greek demigods who have somehow ended up in Roman territory. With his memories, he'd be more aware of the signs and ways to track them down. He could also be on a mission to discover the secrets of the Roman gods that the Greeks don't know much about, in order to strengthen the relationship between the two pantheons. And he might get involved in a battle against some ancient monster that the Romans thought was long defeated but Percy knows is still a threat due to his past experiences.
Well, Percy could inherit enhanced senses like acute smell and hearing from Lupa. This would make him even better at detecting danger. Also, he might get some sort of connection with wolves, being able to communicate or at least understand them to some extent. Maybe he could run faster and have more stamina in wolf - like ways, which would be super useful in battles or during long chases.
It could have the ability to communicate with Harry on a psychic level. Telling him when danger is near or guiding him on how to use its powers most effectively in different situations.