Who could be the main antagonist in 'natsu gets killed fanfiction'?

It could be a power - hungry Pokemon trainer. This trainer might see Gladion as a threat to their goal of dominating the Pokemon league or the entire Pokemon world. So, they plan and execute his killing.

Sasuke could turn into the main antagonist if Naruto is killed. Their bond was so strong, and Naruto's death might break Sasuke completely, leading him to go against everything Naruto stood for and become a new threat.

It could be a dark wizard who wants to use Natsu's connection to the Dragonoid for his own evil purposes. This wizard might have set the trap to either steal Natsu's power or to use him as a sacrifice to gain more power related to the Dragonoid.

It could be an old and powerful vampire lord who sees Natsu as a threat to his rule. Since Natsu is a new and different kind of vampire, the lord might want to eliminate him.

Maybe an ancient dragon that has been awakened from its slumber and views Natsu as an intruder in the dragon world. Since Natsu is a new - made dragon, this old dragon might try to drive him out or even harm him.

It could be another dark mage who sees the potential in baby Natsu and wants to use him for evil purposes. This mage might view Zeref as an obstacle in getting to Natsu.

Maybe there's a dark wizard who has a vendetta against Natsu's family. When he finds out that Natsu is secretly a girl, he sees it as an opportunity to further his evil plans. He could try to kidnap her or use her as a bargaining chip against her family or friends. He might think that because she's a girl, she'll be easier to manipulate or capture compared to if she was thought to be male.

It could be a dark wizard who wants to use the baby's power for his own evil deeds. Maybe the baby has some special magic that the wizard thinks can help him take over the magical world.

Obviously, the Dursleys themselves are the main antagonists. Vernon Dursley, with his short temper and extreme dislike for anything out of the ordinary, could be the driving force behind Harry's death. He's always been shown to be cruel to Harry in the original series. Petunia Dursley, too, could play a major role. Her envy of her sister and her hatred for Harry could lead her to either directly cause his death or be complicit in it. And Dudley, with his spoiled and bullying nature, might also be a key figure in Harry's demise.

Another option is a group of anti - magic fanatics. They view Percy's wings as an abomination because they are a result of magic. They hunt Percy down, believing that by getting rid of him and his wings, they are protecting the world from the 'evils' of magic.