In these fanfictions, Harry's character transformation is quite drastic. He loses his sense of morality. His loyalty, which was once towards his friends and the good side, now shifts to Voldemort. He becomes more power - hungry, willing to do whatever it takes to gain more power, including using dark magic without hesitation. He also becomes more secretive and manipulative, using his former relationships to further Voldemort's goals.
In such fanfiction, a common plotline is that Harry's decision to join Voldemort creates a power shift. He might use his status as the 'Boy Who Lived' to undermine Dumbledore's reputation further. Since many in the wizarding world had put their faith in Harry, his joining Voldemort could lead to widespread panic and confusion. Harry could also start to recruit other disillusioned wizards to Voldemort's cause, using his own charm and the false narrative that Voldemort is actually a liberator of the wizarding world from the old, restrictive ways.
Well, it could be that Evil Harry is actually a long - lost relative of Voldemort in this fanfiction. He discovers this connection and, feeling a sense of kinship with Voldemort's ideology of pure - blood supremacy, decides to join him. He then uses his skills at Hogwarts, like his knowledge of spells and potions, to enhance Voldemort's army. He might also be involved in turning some of his classmates to the dark side, creating a rift within Hogwarts between those who follow him and those who oppose Voldemort's new ally.
Snape could play a crucial role. Given his past with both Voldemort and his role at Hogwarts, he might be torn between his loyalty to Dumbledore's cause and his complex relationship with Harry. He could be the one who has to make a difficult decision when Harry starts to side with Voldemort. Additionally, Draco Malfoy could be involved. He might see Harry's change as an opportunity to gain more power within Voldemort's ranks, or he could be jealous of Harry's new - found position with the Dark Lord.
Yes, it is considered controversial. Harry Potter is traditionally seen as the hero who opposes Voldemort, the ultimate villain. The idea of him joining Voldemort goes against the core values of the original story. Fans of the original series often have strong emotional attachments to the characters as they are in the books, and this concept can be seen as a perversion of those characters.
Perhaps Harry joins Voldemort out of a sense of hopelessness. After seeing so much destruction in the wizarding world, he might think that joining Voldemort is the only way to end the war quickly. However, he soon realizes that Voldemort's methods are too extreme and tries to find a way to turn things around from within the dark side.
In this fanfiction scenario, it could be that Voldemort was misunderstood due to a long - standing feud between two powerful wizarding families. The real motives of Voldemort were to bring equality among all wizards, regardless of their blood status. Harry, who has always fought for justice, sees the potential in this 'good' Voldemort and decides to join him. They then start a journey to change the perception of the wizarding society towards Voldemort and his ideas.
In some versions of this type of fanfiction, there could be a time - travel element. Harry travels back in time and ends up getting involved with a younger Voldemort. He sees potential in Voldemort that he believes can be redirected for good, but instead, he gets drawn into Voldemort's dark plans. As a result, he begins to work with Voldemort against the very people he once called friends and allies.
The Death Eaters would initially be overjoyed. They would think that with Harry on their side, they are invincible. But some of them might also be suspicious of Harry's motives, fearing that he is a double - agent. As for the general wizarding population, they would be terrified. Harry was seen as their hope, and now that he has joined Voldemort, they would feel completely hopeless and defenseless.
Well, in a fanfic where Harry joins Voldemort, it could be a very different story. Harry could start to learn the dark arts from Voldemort, which would change his character completely. He might be given new powers or abilities that are dark in nature. This would also cause a lot of confusion among the wizarding community. People who once looked up to Harry would be disappointed and afraid. And there would be a new dynamic between the Death Eaters and Harry, with some perhaps being jealous of the attention he gets from Voldemort while others might try to befriend him for their own gain.