A third plotline could be Percy being raised by the gods in a different era. He might be sent back in time to the age of the Titans and have to grow up among them while still retaining his loyalty to the Olympians. This would create a lot of internal conflict for Percy as he tries to figure out how to survive and still uphold his values.
In some 'Percy Jackson Raised on Olympus' fanfictions, there could be a plotline about Percy uncovering long - hidden secrets of Olympus. For example, he might discover a forgotten prophecy that has implications for the entire pantheon. Also, his interactions with the nymphs and other mythical creatures in the Olympian realm can make for an exciting story. Maybe he has to protect them from a new threat that is emerging within the boundaries of Olympus itself.
Well, it could start with Percy being framed for a crime he didn't commit by the gods. This false accusation makes him feel extremely betrayed. He then has to go on the run while trying to prove his innocence. Along the way, he meets other outcasts and together they form a resistance against the gods. They might try to find a way to hold the gods accountable for their actions and create a new order where demigods are treated more fairly.
A third plotline might be Percy's newfound powers or abilities due to being raised by the Hunt. He could develop enhanced senses, like better vision at night or a keener sense of smell. This would not only help him in hunting but also in facing off against enemies. He could use these powers to protect the Hunt from threats that they haven't encountered before.
Well, of course, Percy Jackson himself is the central character. He's the one being raised by the gods, so everything revolves around him.
A possible plotline could be that the hermit is actually a forgotten hero from the past. He has been in hiding all this time but now his past is catching up with him. As he tries to keep his identity a secret, events unfold that force him to face his former life and the consequences of his actions long ago.
One interesting plotline could be the Seven facing a new, more powerful enemy that is a combination of different mythological creatures. This would test their teamwork and individual powers in new ways.
One interesting plotline could be Percy having to face a new and powerful ancient evil that the gods are also afraid of. This would put him in a position where he has to use his wits and powers in ways he hasn't before.
Maybe in the fanfiction, Percy's player side shows up when he has to navigate the complex social hierarchies of the demigod world. He could be seen charming different groups of demigods, from the children of Athena with his quick - witted remarks to the children of Aphrodite with his newfound 'player' charisma. This could lead to all sorts of adventures and conflicts as he tries to maintain his relationships while also keeping up his player image.
One interesting plotline could be the siblings going on a secret quest together without the knowledge of Chiron or the other campers. They might face a new and unknown monster that tests their combined skills.
In some fanfictions, a centurion discovers a long - lost prophecy that involves Percy. This could lead to a race against time as they try to figure out the meaning of the prophecy and prevent a great disaster. Maybe it involves a new Titan rising and they need Percy's unique connection to the sea gods to stop it.