The Titans could be antagonists. Since Nyx is an ancient and powerful goddess, the Titans might see Percy as a threat because of his connection to her. They could try to either turn him against Nyx or simply eliminate him.
One idea could be Percy's struggle with his new identity as Nyx's adopted son. He might face discrimination from some of the other demigods who are suspicious of his new connection. Another plot could involve Percy learning new powers from Nyx that set him apart in battles against monsters. He could also have to deal with Nyx's enemies who target him because of his relation to her.
Developing his powers further is also a way. Since he's the son of Nyx, he could learn to manipulate different aspects of darkness like creating illusions using shadows or traveling through the dark realms faster. This would not only make him more powerful but also show his growth as a character as he masters these new abilities.
In this fanfiction, there might be a lot of focus on Percy's relationship with the other wolves in Lupa's pack. He could learn their ways of survival, their hierarchy, and how to be a part of their community. This would be a great way to explore his adaptability and growth.
One common theme is the struggle with identity. Since Percy is the son of Erebus and Nyx in these fanfictions, he often has to grapple with being different from the 'canon' Percy. Another theme is power. Given his new parentage, he might have different or enhanced powers, and the fanfictions often explore how he uses or controls them.
Another plotline could involve Percy exploring the powers he has inherited from Chaos and Nyx. Maybe he discovers unique abilities that no one has ever seen before, like the power to manipulate shadows in a way that's different from a child of Hades. This could lead to him going on a journey to understand the full extent of his powers and how to control them.
One idea could be Percy having to face a new type of monster that is related to Nyx's powers. For example, a shadow - creature that can only be defeated by using the unique abilities he inherits from being the son of Nyx.
Well, of course, Percy Jackson himself often makes an appearance. He could be a mentor figure to the adopted son, guiding him through the ropes of being a demigod. Annabeth is also common, perhaps helping the adopted son with her wisdom and knowledge of the mythological world.
The setting of the story might shift a bit. Instead of always being at Camp Half - Blood or on quests related to the Greek gods, Percy could be in the territory of the wolves. There could be new threats and challenges there, like rival wolf packs or ancient enemies of Lupa. And all these elements would make for an exciting and different take on the Percy Jackson universe.
Well, obviously Percy himself. Since he is the son of Chaos and Nyx in this fanfiction, he is the central figure. Annabeth is often included too. Her relationship with Percy, whether it's evolving or being tested due to his new status, is a key aspect. There could also be other demigods like Grover. He might be there to support Percy or be a bit wary of his new powers.