Another possibility is that Percy discovers some long - forgotten weakness of Zeus. In the world of fanfiction, the author could create a scenario where Percy stumbles upon an ancient prophecy or a hidden secret about Zeus. This knowledge could give Percy the upper hand. He could then use his wits and his powers to exploit this weakness and defeat Zeus.
In this kind of fanfiction, Percy might challenge Zeus over issues like the unfair treatment of demigods. For example, Zeus could be overly harsh on demigods who make minor mistakes while the gods themselves get away with much worse. Percy, being a hero, would stand up for his fellow demigods.
Percy has his speed and agility. In the fanfiction, he might be able to use his demigod reflexes to dodge all of the Avengers' attacks. He could then quickly move in for a counter - attack. Also, his sword, Riptide, is a powerful weapon. It can cut through almost anything. He could use it to cut through the Avengers' weapons or their defenses if he gets close enough.
Percy Jackson is really good at improvising in battles. He might use the environment to his advantage. If they are in a place with water sources, like near a river or a lake, Percy can summon huge waves to knock Galbatorix off his feet. And considering Percy has faced powerful foes before, he won't be intimidated easily. He could also use his speed and agility, which he has developed from his years of fighting monsters, to dodge Galbatorix's attacks and get in close for a killing blow.
One interesting fanfiction could be about Percy Jackson's adventures that are more closely tied to his relation as Zeus's grandson. Maybe he discovers some hidden powers that are passed down only through the Zeus lineage. He could face challenges where his Zeus - related powers are both a blessing and a curse, like when he has to control excessive lightning powers during a battle with a powerful monster.
In some fanfictions, Zeus interacts with Percy in a hostile way at first. He sees Percy as a threat to his power and the order of Olympus. For example, he might try to limit Percy's abilities or send challenges to prove Percy's unworthiness.
One possible plot could be that the entire Greek pantheon is thrown into chaos. Percy might be seen as a huge threat, and other gods and goddesses would either try to hunt him down or form alliances with him out of fear or a desire for power. Demigods would be forced to take sides, leading to massive battles among them.
Well, one possible plot could be Percy discovering he's Zeus' brother in a very unexpected way. Maybe through some ancient prophecy that was long forgotten. He'd then have to deal with the power struggles within the Olympian family, as well as his own identity crisis. Another aspect could be his relationships with other demigods changing, as being related to Zeus is a huge deal.
Well, the plot could be centered around Percy's attempts to bridge the gap between his father Poseidon and his grandfather Zeus. There have always been tensions between the two gods. Percy, using his unique position, tries to bring peace. But there are forces at work, like some rogue demigods who don't want peace between the two powerful gods. They try to sabotage Percy's efforts, leading to a series of adventures and challenges for Percy.
Well, one possibility is that Percy, being blessed by Zeus, could face a moral dilemma. On one hand, he has his loyalty to Poseidon, his father. But the blessing of Zeus comes with certain expectations. He might be caught in the middle of a power struggle between the two gods, and have to decide how to use the new - found powers without angering either of them.
Well, it could be about the daughter of Zeus trying to fit in at Camp Half - Blood. Maybe she has powers that are hard to control, like being able to summon huge lightning bolts at unexpected times. She might struggle with the expectations that come with being the daughter of the king of the gods.