Another reason could be emotional stress. Peter in the Avengers world has a lot on his plate. He's a young hero trying to balance school, his personal life, and his superhero duties. In fanfic, the writer might make him faint from the overwhelming pressure of dealing with, say, the loss of a loved one or the fear of not being able to protect his city.
It could also be due to some sort of external influence like a new and unknown power or a villain's weapon. Maybe he's exposed to a strange energy that his body isn't used to, and it causes him to faint as his body tries to adjust or fight off the effects.
In some fanfics, Peter might faint due to overexertion. He's often depicted as being involved in intense battles or using his powers to the extreme. For example, if he's been fighting a powerful villain for a long time without a break, his body could just give out and he faints.
It could also be due to jealousy. Peter might be getting too much attention from the public or other superheroes. His youth and new - found popularity could make the more established Avengers feel overshadowed, leading to feelings of resentment towards him.
It could be that Peter's immaturity showed in a crucial situation. He might have been over - confident and tried something really risky without thinking it through. The Avengers, being more experienced, would be frustrated with his recklessness and thus yell at him. They want him to learn and grow, but his actions might have been too much to tolerate at that moment.
He might also get angry. Peter has a strong sense of justice. If he feels that the Avengers are being unfair, he could stand up to them. He'll use his quick wit and his powers to show that he's not going to be pushed around easily.
In some fanfiction, Peter Parker might leave the Avengers because he feels out of place. Maybe he realizes that his style of heroism doesn't quite fit with the more organized and sometimes bureaucratic way the Avengers operate. He could also leave due to personal reasons, like wanting to focus more on protecting his local neighborhood in Queens rather than getting involved in global Avengers - level threats.
Peter might be very defensive at first. He could argue back, trying to explain his actions. After all, he is a teenager with his own ideas and he may think that the Avengers don't fully understand his perspective.
Well, it could be due to misunderstandings. Fanfics often play with the idea that Peter, being young and inexperienced, might accidentally cause trouble that the Avengers misinterpret as intentional. For example, he could be trying to help but ends up making a situation worse, leading to the Avengers' dislike. Another reason could be that some writers like to create drama by pitting characters against each other. They think it makes for a more interesting story if the Avengers have this negative view of Peter Parker, even if it goes against the more positive portrayals in the official comics or movies.
Well, if Peter dies in an Avengers fanfic, it can have a huge impact on the storyline. For one, it would be a great shock to the other characters. Tony, who was like a father figure to Peter, would be devastated. His death could also be a turning point for the remaining Avengers. They might become more determined to fight against the villains in Peter's memory. It could also lead to new alliances being formed as they try to fill the void left by Peter.
Peter usually blushes a lot. Since he's a shy and somewhat awkward teenager, his face turns bright red when the Avengers embarrass him. He might stutter while trying to defend himself or come up with an excuse.
In fanfictions, the Avengers are often overprotective of Peter because he's young and inexperienced compared to them. He's like a little brother or a son figure to many of them. For example, Tony Stark sees in Peter a younger version of himself and wants to prevent him from making the same mistakes he did. So, he's overly cautious.
Well, Bruce could leave in fanfic for the sake of self - discovery. He's constantly struggling with his identity as Bruce and as the Hulk. Fanfic authors might write him leaving to find a place where he can better understand himself without the distractions and pressures of the Avengers team.