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.
Percy would probably be very confused at first. He's used to dealing with threats from the world of Greek mythology, not superheroes like the Avengers. But once he realizes he's been kidnapped, he'd likely be angry. He'd try to find a way to escape using his powers, like controlling water to create distractions or even using it to overpower his captors.
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.
Well, initially, the Avengers would be quite skeptical. I mean, they deal with high - tech and super - soldier stuff. But once Percy shows what he can do, like summoning a giant sea monster to help in a battle, they'd start to see the value. Iron Man would likely try to find a scientific explanation for Percy's powers and might even try to replicate them in some way. Captain America would appreciate Percy's courage and how he uses his powers for good, just like he does with his own abilities.
One way could be to have Percy Jackson's powers of being a demigod interact with the superpowers of the Avengers. For example, his ability to control water could be used in a joint mission with Thor's lightning powers. Maybe they are facing a common enemy that can only be defeated by combining their unique skills.
A possible fanfiction could involve a crossover where some of the Avengers are sent to Camp Half - Blood. Imagine Tony Stark trying to figure out how the magic at the camp works while also being highly amused by the whole concept of demigods. Steve Rogers could bond with some of the more heroic demigods over their shared sense of duty. Meanwhile, Percy and his friends have to keep an eye on the Avengers to make sure they don't accidentally disrupt the delicate balance of the camp. And then, they all have to face a threat that targets both the Avengers and the demigods, like a group of villains who want to steal the powers of both.
There are so many fanfictions out there that it's hard to determine if there's a popular one with this specific plot. The Percy Jackson and Avengers fanfiction communities are quite large, but this concept goes against the general heroic portrayals in both universes. It's less likely to gain widespread popularity, but it doesn't mean there aren't some well - written ones out there that a small group of fans might really like.
Another option could be Black Widow. She's very good at adapting to new situations and using her skills in different ways. For Percy, who is coming from a very different world, she could teach him how to be stealthy and use his powers in a more covert way. She could also help him with understanding the political side of the Avengers, like dealing with government agencies and such, which Percy may not be used to in his world of demigods.
Well, in some fanfiction scenarios, Percy Jackson might betray the Avengers due to a misunderstanding. Maybe he's been misinformed about the Avengers' intentions towards the demigods. For example, if he hears false rumors that the Avengers plan to control the demigods, he could turn against them in a fit of protectiveness for his kind.
Well, Percy could use his water - controlling abilities to put out fires during the Avengers' battles. His skills with a sword could also be useful in close - combat situations against the bad guys.