The plot could involve an ancient artifact that the Avengers find. Unbeknownst to them, it has the power to summon a great evil from Percy Jackson's world. When this evil arrives, it starts to overpower the Avengers. Percy senses the disturbance and comes to the rescue. He and the Avengers must then work together to figure out how to send the evil back and keep the artifact safe, with Percy using his knowledge of ancient magic and the Avengers using their technology and superpowers.
Maybe the Avengers are under a curse that is slowly draining their powers. Percy, being a demigod, has some knowledge of curses. He hears about the Avengers' plight and decides to help. He embarks on a journey to find the source of the curse, facing many challenges along the way. Once he finds it, he uses his powers and the help of the Avengers (even with their weakened state) to break the curse and save them.
Well, Percy could use his water powers to put out any fires or floods that the Avengers might be facing. His ability to control water could also be used to create barriers against enemies. For example, if the Avengers were up against a powerful fire - based villain, Percy could summon a huge wave to douse the flames and save the day.
One possible plot could be that the Avengers mistake Percy Jackson for a dangerous threat. Maybe they've been given false information about his powers being uncontrollable. So, they decide to kidnap him to keep the world safe. But once they have him, they start to realize that he's not what they thought. Percy, being a hero in his own right, tries to convince them that he's on the side of good.
One possible plot could be that in a world where the gods of Percy Jackson and the Avengers co - exist, Percy is somehow tricked or forced to banish the Avengers. Maybe there's a power struggle among the gods and they see the Avengers as a threat to their power, so they use Percy, who has a strong connection to the divine world, to get rid of them. Percy might be conflicted as he may admire the Avengers' heroism but has to follow the gods' orders.
One possible plot could be that the gods in the Percy Jackson universe sense a great threat from another dimension (the Marvel universe). Percy and his friends are sent to team up with the Avengers. Percy's water powers could be useful in fighting villains like Electro. Annabeth's strategic mind would assist in planning battles against foes like Loki. They all have to learn to work together, with Percy and the Avengers initially having some clashes due to their different ways of handling things.
In a 'Percy Jackson Saves Tony Stark' fanfiction plot, Stark could be on a mission in a remote area that has some hidden mythological secrets. He unknowingly awakens an ancient evil. Percy Jackson, who is nearby on a quest of his own, notices the disturbance. He races to save Stark. Percy has to deal with his own personal demons as well as the new threat. He saves Stark by using his demigod powers in creative ways, like using the water in the environment to create shields or using his ability to read ancient languages to decipher a way to stop the evil. After that, they join forces to make sure the area is safe again and Stark is inspired by Percy's world to create new tech that can detect and deal with mythological threats.
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.
If Percy saves Zoe, it would likely have a significant impact. Maybe it unlocks hidden powers for Percy or makes Zoe more dependent on him. There are so many possibilities for how this could unfold.
One possible plot could be that the Greek gods, noticing the powerful threats the Avengers face, send Percy Jackson and his friends to help. Percy could use his water powers to assist in putting out fires during a battle like the one in New York. Meanwhile, Thor could be intrigued by Percy's connection to Poseidon and they could exchange stories about their godly fathers.
Well, perhaps she's on a quest. The Avengers mistake her for a threat at first. She's looking for a magical artifact that has the potential to either save or destroy both the demigod and superhero worlds. Along the way, she teams up with some of the younger Avengers like Spider - Man or Shuri. They don't trust each other fully at the start, but as they face various challenges together, they start to respect and rely on one another. And she's constantly in touch with her demigod family, getting advice from them about how to handle the superhero situation.
One possible plot could be that the Avengers mistake Percy for a threat. Maybe they see his powers with water and think he's some kind of new, unknown enemy. They capture him to figure out what he is. Percy, of course, would be confused and probably a bit angry at being wrongly accused.