In this fanfiction scenario, it could be that the writer decided to change the power dynamics completely. Vernon, who is usually just a Muggle bully in the original, might be given some unexpected power or weapon in the fanfic. And Harry, perhaps caught off - guard or having lost his magic temporarily, could be killed by Vernon. It shows how fanfiction can turn the whole story upside down.
Fanfiction often takes creative liberties. For this 'harry potter is killed by vernon' idea, it might be that the writer is trying to make a statement about the vulnerability of even the most powerful characters. Maybe Vernon represents the ordinary world's unexpected and underestimated threat to the magical world. Harry's death at his hands could be a shock factor to make readers think about the fragility of the 'chosen one' concept.
In this kind of fanfiction, perhaps Harry, out of fear or some form of coercion, starts to obey Uncle Vernon's every order. Maybe Vernon uses threats about expelling Harry from the house or withholding food to make him submit. This could lead to a very different dynamic in the Dursley household, with Harry being more submissive and not showing his usual defiance.
Hermione would probably be devastated. She was Harry's closest friend and ally. She might be filled with rage towards Vernon and vow to seek justice. Ron would also be heartbroken and might want to take matters into his own hands against Vernon.
Well, perhaps Vernon might beat Harry out of his extreme dislike for magic. He could be enraged by some accidental magic Harry does at home and lose his temper completely.
In this fanfiction, perhaps Dudley's envy of Harry's magical world finally boiled over into uncontrollable rage. He might have found a way to cross into the wizarding world without anyone knowing. And in a moment of extreme jealousy and anger, Dudley could have used some kind of weapon or spell (maybe through some dark magic loophole) against Harry, which unfortunately led to Harry's death. Fanfiction allows for these extreme and unexpected plot twists.
In some dark fanfiction scenarios, Vernon might kill Harry Potter out of his extreme hatred and fear of magic. Maybe he discovers Harry's magic in a moment of rage and overreacts, using a weapon or his brute force to end Harry's life. However, this goes completely against the essence of the original series where Vernon was more of a bumbling, non - magical threat.
One possible motive could be his intense hatred for the wizarding world. Since Harry represents that world to him, he might murder someone he believes is part of the magic that he despises so much. Another motive could be fear. If he feels threatened by a magical being or situation, in his panicked state, he could resort to murder.
One possible plot could be that the Dursleys, out of their long - held hatred and envy, finally find a way to use dark magic against Harry. Maybe they make a deal with some dark wizards who provide them with a powerful curse. They manage to cast it on Harry when he's at his weakest moment, perhaps during one of his vacations at Privet Drive.
There might be some extremely dark and non - canon fanfictions out there with such a disturbing plot. However, this goes against the general spirit of the Harry Potter series. In the official story, Harry is a hero who overcomes great challenges. In a fanfiction with this idea, perhaps it could be due to extreme despair from losing too many loved ones or feeling an overwhelming burden of his destiny that he snaps and takes his own life. But again, this is a very unorthodox and sad take on the character.
It might be a fan who was really intrigued by the relationship between Harry and Vernon and decided to take it to an extreme in their writing. There are so many fanfiction writers out there, some write for fun, some to explore different character dynamics. So, it could be anyone really.
Well, one way could be through some dark and misinterpreted magic. Maybe Harry stumbles upon an ancient spell that he thinks will defeat Voldemort once and for all but instead, it backfires and revives him. It could also be due to some sort of interference from a powerful dark object that Harry unknowingly uses in the wrong way.