In this fanfiction, perhaps there's a device that can only be activated when all the Avengers are assembled. They start off scattered due to personal differences and misunderstandings. But as they gradually come together, they not only become strong enough to activate the device which can save the world from an approaching alien invasion but also learn the true meaning of teamwork and unity.
It could be about the Avengers coming together after a major setback. Maybe they've lost a big battle against a powerful new villain. But then they realize that by truly assembling as a team, sharing their powers and strategies, they become strong enough to take on the foe. For example, Iron Man could combine his technology with Thor's magic in a way they hadn't thought of before.
A technologically advanced alien race could be the main antagonist. They have studied the Avengers and know their weaknesses. They attack Earth in a way that isolates each Avenger at first. But when the Avengers assemble, they use their combined strength to hack into the alien technology, reverse - engineer it, and turn it against the aliens.
In this Avengers assemble dracula fanfic scenario, the Hulk might be a wild card. He could just smash Dracula without much thought. But Dracula is not an easy foe. He has centuries of combat experience. Black Widow and Hawkeye would also play important roles. Black Widow could use her combat skills and intelligence to find Dracula's lair and Hawkeye could shoot his arrows, perhaps ones with silver tips which are effective against vampires.
Well, it could be about the Avengers having to take care of a baby. Maybe they find the baby during one of their missions and have no idea what to do at first. They might struggle with changing diapers, feeding the baby, and making it stop crying. But in the end, they all grow to love the baby and it becomes like a little mascot for the team.
Perhaps it's about the Avengers' internal relationships. They might have been wrong about one of their members, like misjudging someone's loyalty or intentions. This could lead to a rift within the team, and the fanfiction could detail how they deal with this realization and try to fix things.
Well, one possible plot could be that Peter has some sort of special connection with each of the Avengers. Maybe he has a unique power that only activates when he's near them, and they gradually realize he's like a missing piece to their team. They start to protect him and he in turn helps them with his intelligence and quick thinking.
In this fanfiction, Daisy might have some initial struggles to fit in with the Avengers. She could be from a different background or have a different approach to fighting. But as time goes on, she starts to bond with the team members, like sharing combat strategies with Black Widow or having a friendly rivalry with Thor in terms of strength. And she eventually becomes an integral part of the team.
It could involve the next - generation heroes facing a new and powerful villain that the original Avengers couldn't defeat. Maybe they have to use new powers or technology.
Well, one possible plot could be that during a big battle where the Avengers and Spiderman are fighting side by side against a powerful enemy like Thanos. Spiderman, being young and perhaps a bit over - eager, jumps into a dangerous situation without proper backup. He gets injured while trying to protect an Avenger, say Captain America. This could lead to a lot of guilt among the Avengers for not being able to protect him better and also Spiderman having to deal with his own physical and mental recovery.
A really interesting plot for this fanfiction could be that the Avengers are somehow drained of their powers and they need to find a way to get them back. They hear about the power of the Greek gods from 'The Lightning Thief'. So they travel to that world and meet Percy. Percy, being the hero he is, decides to help them. They then go on a journey through the different realms of the Greek gods, facing monsters and challenges together. Along the way, the Avengers learn about the importance of teamwork in Percy's world and Percy learns some new combat and strategic skills from the Avengers.
The plot could involve Castiel being summoned by a magical accident in the Avengers' universe. He then realizes that there is a great evil approaching, something that not even the combined might of the Avengers can handle. So, he decides to use his knowledge of the supernatural and his powers to help them. He might have to teach the Avengers about the existence of angels and other celestial beings to make them understand the true nature of the threat. Along the way, there could be some really interesting interactions between Castiel and the different Avengers members. For example, his stoic and otherworldly nature could contrast with Tony Stark's sarcastic and scientific mind, leading to some great dialogue.