Well, if Percy was more powerful, he could act as a stronger mediator between Zeus and Poseidon. He might be able to force them to face their issues more directly. For example, he could use his increased power to create situations where they have to work together, like in the face of a new and extremely powerful enemy. This could lead to a begrudging respect between the two gods and a shift in their relationship from one of constant bickering to a more cooperative one, at least when Percy is around.
She'd likely be extremely powerful. Since Zeus is the king of the gods, she'd probably inherit a great deal of his power over lightning. She could also have some control over the sky, like being able to create storms or clear skies at will.
One great fanfiction idea could be a story where Zeus, Poseidon and Hades have to team up to face a common threat that is even more powerful than them. Maybe a primordial being awakens and they must put aside their differences. In this story, Percy could be the mediator between them, using his unique position as the son of Poseidon to try and keep the peace among the three powerful gods.
In a fanfiction where Percy is the son of Hades and Poseidon, his powers would be truly extraordinary. He could have the ability to create portals in water that lead to the Underworld. This would give him an advantage in both battle and travel. His hydrokinesis could be tainted with the essence of death, so when he attacks with water, it could cause a draining effect on his opponents, sapping their life force. Additionally, he might be able to sense the presence of the dead in any water source, which could be used for both reconnaissance and protection.
A fanfiction could be about a competition among Zeus, Poseidon and Hades, and Percy has to be the judge. The competition could be something like who can best help a small, struggling mortal town without using their full power. This would show a different side of the gods and also test Percy's ability to be fair and objective.
His water - based powers might be more intense. Since he's directly related to Poseidon, he could have greater control over large bodies of water, like being able to create huge tidal waves with just a thought, instead of just small ones. He might also be able to communicate with sea creatures on a deeper level, understanding their complex languages and using them to his advantage in ways he couldn't before.
In fanfiction, their relationship could be developed by having Poseidon be more involved in Percy's daily life. Instead of just popping in during big events, he could be there for the small things too. For instance, helping Percy with his schoolwork that involves marine biology. They could also have a project together like building a new safe haven for sea nymphs. Through this, they would bond over creating something positive. Also, Percy could start to take on some of Poseidon's responsibilities in the ocean, with Poseidon guiding him. This would not only strengthen their bond but also show Percy growing into his role as Poseidon's son.
Their relationship would likely become much closer. Percy would start to see Poseidon as not just a powerful god but also as a father. Poseidon, in turn, would get to know Percy better and might start to teach him more about their family's history.
Well, at first, they might be cautious around each other. Percy is used to being the main hero, and the daughter of Zeus's sudden appearance could make him a bit jealous or at least wary. But as they face challenges together, they start to respect each other. Maybe she saves Percy from a difficult situation, and he realizes she's not just there to steal his thunder. Over time, they could become good friends, relying on each other's unique skills in battles against monsters.
The relationship could be shown as a curious one. Since Percy is a baby, he might not fully understand who Poseidon is, but there could be an instinctual bond. Poseidon, on the other hand, could be filled with a sense of wonder at this small version of his son, seeing all the potential in him. He might try to communicate with Percy in gentle, non - verbal ways, like sending small ripples of water to make Percy laugh.
In some fanfictions, their relationship is one of deep mutual respect. Percy, as Poseidon's son, often seeks his father's guidance. Poseidon, in turn, tries to protect Percy from the many dangers in the demigod world while also teaching him about his powers.