Not having read the 'redemption a harry potter avengers fanfiction', I can only make assumptions about the main characters. It could potentially center around a misfit character from Harry Potter, perhaps Draco Malfoy, who is seeking redemption and teams up with a reformed villain from the Avengers, like Loki. Or it could be about Harry Potter and Thor, both having their own burdens of heroism and they come together in a story about finding a new kind of redemption that combines their different worlds' values and challenges. There are so many possibilities when it comes to combining these two rich universes.
I'm sorry I haven't read this specific fanfiction so I can't really explain the plot.
Thor could be a main character. His godly powers and his somewhat otherworldly nature would add an interesting element to the story. And then there's Snape. His complex personality and his skills in potions and the dark arts could play a significant role, especially if there are plot elements related to poisons or dark magic that the Avengers need to deal with.
Definitely Iron Man and Harry Potter. Iron Man's cool gadgets and snarky personality combined with Harry's magical abilities and heroic nature make them a great pair in crossovers.
Peter Parker (Spider - Man) could also be a great main character for this kind of fanfiction. His youthful charm and heroic nature would appeal to characters in both universes. He could be on a school exchange program in Hogwarts (using some multiverse - like excuse) and during his stay, he gets involved with helping the wizards while also catching the eyes of Ginny Weasley, MJ, and Black Widow, creating an interesting harem situation.
The main character could be Hermione Granger. Since she is very intelligent and has a strong sense of justice, she could easily be re - imagined as a lawyer. She could use her vast knowledge of magic and her quick thinking to bridge the gap between the two worlds and help the Avengers out. For example, if there was a spell that was being misused in the Avengers' world, she could figure out how to stop it legally.
Voldemort could be a likely main antagonist. He's the most powerful dark wizard in the Harry Potter series. He might see the Avengers as a threat to his plans of total domination, not understanding their world but still seeing their power. So, he could use his dark magic to torture them, trying to break their will before eliminating them.
Harry Potter and Captain America are likely to be paired. Harry is used to leading a group against dark forces, and Captain America is a natural leader too. Their leadership styles could complement each other. Also, they both have a strong sense of justice.
To create a compelling redemption arc, it's important to have consequences for the character's past actions. If Captain America made a wrong decision during a battle that led to civilian casualties, he would have to face public outcry and the disappointment of his team. This would force him to re - evaluate his actions and strive for redemption. Writers should also include moments of growth, like Cap learning new strategies to avoid such mistakes in the future.
In fanfiction, Raven could be an interesting addition to the Harry Potter and Avengers universes. Maybe she has some sort of magic ability that links her to the wizarding world of Harry Potter and at the same time, she might possess powers that could make her fit into the Avengers' world. For example, she could be a powerful witch who also has enhanced physical abilities like the superheroes in the Avengers. She might interact with Harry Potter characters by using her unique powers to solve some magical problems at Hogwarts. And in the Avengers' side, she could be a new recruit with her own set of skills and backstory.
A petal could potentially be a character's name or nickname in a fanfic that combines Harry Potter and Avengers. It could be a magical petal that has the ability to transport characters between the two universes. For instance, if a character from the Avengers picks up this petal, they might suddenly find themselves in Hogwarts. Or perhaps it's a petal from a dark magical plant that is being used for evil purposes by a villain who has knowledge of both magical worlds.