Well, a cool plot might involve Percy Jackson being framed for helping the Host of Apophis. He then has to clear his name while also trying to prevent the actual rise of Apophis. Or perhaps Percy discovers that there's a connection between the Host of Apophis and a long - lost relative of his, and he has to figure out how to break that connection without harming his family. Also, Percy could be sent on a quest by the gods where the final destination is the lair of the Host of Apophis, but the journey there is filled with all sorts of traps and tests.
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.
One idea could be Percy discovers new powers as the Host of Chaos and has to learn to control them while facing an ancient enemy that was sealed away long ago. He could struggle with the chaotic nature of his new abilities and how they affect his relationships with his friends at Camp Half - Blood.
Percy is the main character so he'll be there. Annabeth will probably be by his side as she often is in his adventures. Leo Valdez could also be a character in this fanfiction. His mechanical skills might come in handy if there are any traps or devices related to the Host of Apophis. Piper McLean could be involved too, using her charm - speak to influence certain situations. And Thalia Grace, the daughter of Zeus, could make an appearance. Her leadership skills and her ability to call lightning could be important in the fight against the Host of Apophis.
One idea could be a story where Percy Jackson discovers an ancient artifact related to the Host of Nekhbet and has to protect it from evil forces. Maybe it gives him some new powers or knowledge about Egyptian mythology.
One idea could be a quest where Percy and Artemis have to team up to rescue a group of demigods captured by a powerful new enemy. Maybe a Titan who has found a way to drain the powers of young demigods. Percy's skills in water manipulation and combat, combined with Artemis's archery and her connection to the moon, would make for an exciting adventure as they face various challenges along the way.
Well, a plot could involve Percy Jackson stumbling upon a hidden cave where cavemen are in a sort of stasis. When they wake up, they mistake Percy for a god because of his powers. Percy then has to teach them about the modern world while also learning about their primitive yet magical ways of life. Maybe there are ancient artifacts in the cave that are related to the Greek gods and Percy has to protect them from being misused.
One plot idea could be that Percy has to face Arachne in a battle of wits rather than just a physical fight. Maybe Arachne weaves illusions within her webs that Percy has to break through to reach her. Another could be a scenario where Arachne tries to use Percy to get revenge on the gods by tricking him into stealing an important artifact from Olympus. A third idea is that Percy and Arachne form an unlikely alliance when a greater threat emerges that endangers both of their existences.
A plot could involve Percy accidentally stumbling into Artemis' territory. At first, Artemis is angry but then realizes Percy has information about a threat to her hunters. So they start an adventure to stop this threat. During the journey, they learn more about each other's worlds and develop a mutual respect. Or maybe there's a spell that makes Artemis lose her powers temporarily and Percy has to protect her while she regains them.
A possible plot is Percy being sent on a mission by the gods to study a strange phenomenon in the ocean that is affecting both the mortal and demigod worlds. He uses his scientific skills, which he has developed over time, to analyze the situation. He might encounter sea monsters that are acting oddly due to this phenomenon and has to figure out how to stop it. Or perhaps Percy is recruited by a secret scientific organization within the demigod world that is trying to find a way to bridge the gap between the magic of the gods and modern - day mortal science. He could bring a unique perspective with his experiences as a demigod.
A really interesting plot could be that Cupid, for some reason, decides to make Percy the ultimate symbol of love in the demigod world. Percy is then thrust into a role he doesn't understand, having to deal with love - sick demigods coming to him for advice. Meanwhile, he has his own relationship problems, like his feelings for Annabeth being complicated by this new status. He has to figure out how to handle Cupid's meddling and restore some normalcy to the love lives of those around him.