For a marvel's avengers game fanfiction plot, you could focus on the relationships within the team. For instance, what if there was a rift between Iron Man and Captain America again, but this time it was caused by a misunderstanding about a new technology that could potentially save or destroy the world. Or perhaps a story where Thor brings a new Asgardian to Earth to train with the Avengers, but this new character has a dark secret that endangers the team. Additionally, a plot where the Hulk goes on a solo adventure and discovers a hidden part of himself that changes his relationship with the rest of the Avengers would be an engaging read.
One idea could be Captain Marvel bringing back some alien tech that the Avengers have to figure out how to use. It could lead to new powers for some of the members or a new way to defend Earth.
A great concept for Marvel Avengers crossover fanfiction is to have the Avengers cross paths with the Fantastic Four. The two teams could collaborate on a scientific project that goes awry, creating a new threat that only their combined powers can defeat. Another possibility is a crossover with the Eternals. Since the Eternals have been on Earth for a long time but hidden, their discovery by the Avengers could lead to a complex relationship. They might initially be at odds, but then realize they need to work together to stop a greater evil that is awakening on Earth. Also, an Avengers crossover with Blade would be interesting. Blade could seek the Avengers' help in fighting a new breed of vampires that are more powerful than ever and have ties to some dark magic that the Avengers have to figure out.
A plot could be about an alternate universe where Captain Marvel is initially distrusted by the Avengers. She has to prove herself and in the process, they all learn more about each other's powers and pasts. This could lead to some great character development and new alliances within the team.
Imagine a fanfiction where Captain Marvel uses her energy - based powers in a completely new way during the final battle in Avengers: Endgame. Instead of just punching and flying around, she could manipulate the energy fields in a way that disrupts Thanos's entire army. This would be a creative take on her character and her abilities.
A really cool plot idea could be that the Avengers are watching Endgame in a sort of 'alternate reality cinema' where the events in the movie start to bleed into their real world. So they have to stop the movie from fully playing out to prevent chaos in their own universe. This would involve a lot of action and strategic thinking as they try to stop things like Thanos from emerging from the screen while also trying to understand the significance of what they're seeing in the movie.
A great Avengers game fanfic idea might be to focus on the relationships within the team. Say, a story where Thor and Loki have to work together to save Asgard from a threat that only they can understand due to their shared history. This could involve a lot of emotional turmoil as they deal with their past issues. Another concept could be a fanfic where Black Widow takes on a mentorship role for a new female superhero who is struggling to find her place in the world of the Avengers. The fanfic could explore themes of female empowerment and friendship within the superhero context.
One idea could be that the mutants and the Avengers have to team up against a common enemy that is immune to their individual powers. So they must learn to combine their abilities in new ways. For example, Wolverine's healing factor could be used to keep an injured Avenger alive during a long battle while Iron Man figures out a way to defeat the enemy.
One idea could be that Harry Potter is magically transported to the Avengers' universe. He could use his magic to help the Avengers in battles, like creating protective shields with spells. Another idea is that the Avengers are somehow sent to Hogwarts, and they have to learn about magic while also dealing with threats in the wizarding world. For example, Iron Man might try to figure out how to integrate his technology with magic.
One idea could be exploring the family dynamics when the Avengers have to take care of a young superhero in training. It would be fun to see how they each contribute to the kid's growth, like Tony Stark teaching about technology and Captain America instilling values.
One idea could be the Avengers facing off against a new, powerful villain who has the ability to turn their own powers against them. This would lead to some really intense battles and strategic thinking on the Avengers' part.