A plot could involve Percy being sent on a mission to an ancient Egyptian underworld realm by Sobek. There, he meets various Egyptian deities and creatures. He has to use his skills as a demigod and his new powers from Sobek to navigate through the dangerous realm and return to the mortal world with important information for the safety of Camp Half - Blood.
Maybe Percy discovers a hidden power within himself that is related to Sobek. For example, he could gain the ability to control water in a more primal and fierce way, like Sobek does. He then has to learn to control this new power while facing off against an enemy who wants to use it for evil. This could lead to some intense battles and character growth for Percy.
A possible plot could be that there is a prophecy that only Percy and the Host of Sobek can fulfill. It involves finding a lost artifact that has the power to either save or destroy the world. Along the way, they face internal conflicts as their different cultures and beliefs clash, but they learn from each other and grow stronger as a team.
Annabeth could be a great ally. She's smart and resourceful, and she could help Percy figure out the mysteries related to Sobek and his Egyptian connections. Her knowledge of architecture and strategy would be useful in any quests Percy undertakes.
Well, a great plot idea might be Percy getting involved in a sky - realm war. He has to use his newfound 'Son of the Sky' abilities to lead an army of sky creatures against an evil force. This would involve him making alliances with different beings, like the winged horses or the cloud nymphs. And he'd have to learn how to fly better to be more effective in the battles. Also, his relationships with his friends from Camp Half - Blood would be put to the test as they might not fully understand his new role.
One idea could be Percy discovers a new, forgotten power related to his 'son of love' aspect. Maybe he can heal emotional wounds of other demigods. For example, he helps a demigod who has been traumatized by past battles by using this power.
One idea could be Percy having to prove his divinity in a new way. Maybe he has to face a trial set by the gods where he can't use his usual powers but has to rely on his wits and faith. Another could be Percy interacting with a different pantheon's deities who mistake him for one of their own sons of god. He'd have to navigate their culture and rules.
One idea could be Percy having to face a new water - based monster that is specifically related to the rivers. Maybe it's a shape - shifting creature that can only be defeated by using the unique powers of the rivers. Another plot could involve Percy exploring the origins of his connection to the rivers more deeply and uncovering a long - lost prophecy about a'son of the rivers' that changes his view of his destiny.
One idea could be Percy having to face challenges in a world where Gaea has more direct control over the elements. For example, the earth itself could be constantly shifting and changing, creating new terrains and obstacles for him to overcome. Another could be Percy forming an unlikely alliance with some of Gaea's other children who are also having second thoughts about their mother's destructive plans.
One idea could be Percy having to hide his true parentage from his friends at Camp Half - Blood. He might struggle with the dark powers that come with being Typhon's son while trying to fit in with the demigods who are mostly children of the Olympians. Another plot could involve Percy being hunted by both the Olympians and the monsters because of his unique heritage. The Olympians might see him as a threat, and the monsters might want to use him for their own purposes.
One idea could be Percy discovering new powers related to being the son of Persephone. For example, he might be able to control plant growth in unique ways during battles, like making vines entangle his enemies. Another could be his relationship with the Underworld changing. Since Persephone has a connection to the Underworld, Percy might have a special status there and encounter new mythological creatures or challenges.