Who could be the main antagonist in 'anna gets powers fanfic'?

Maybe she discovers she has super strength and uses it to protect her town from villains.

Maybe the main antagonist is an old enemy of Robin's who becomes jealous of his new powers. This enemy then devises a plan to steal Robin's powers or at least neutralize them so that he can regain his former status as the top threat. He could be a powerful martial artist or a criminal mastermind with a large network of henchmen.

A new character could be introduced as the main antagonist. Maybe a powerful alien who sees Kim's new powers as a threat to his plan of taking over the earth. This alien could have his own set of powers that are quite different from Kim's, like the ability to control minds. Kim would have to not only learn to use her new powers but also find a way to defeat an enemy with such a dangerous ability.

It could be another person who also has some sort of mind - controlling abilities and wants to use the boy's powers for their own evil plans. This antagonist might try to trick the boy into using his powers in the wrong way.

It could be another character who is jealous of Lucy's new powers. Maybe a classmate or a rival in her community who wants those powers for themselves and will do anything to take them from Lucy.

It could be a jealous rival from her past who is afraid of her return and the attention she might get. This person might try to undermine her at every turn.

Another possibility is that one of Leo's classmates becomes jealous of his powers. This classmate could start spreading rumors about Leo, trying to turn everyone against him. Eventually, the jealousy could turn into something more sinister, and the classmate could team up with some bad elements to try and take away Leo's powers.

It could be a jealous demigod. Maybe someone who has always been envious of Percy's popularity and power. This demigod could spread lies about Percy that lead to his disownment, making them the main antagonist.

The main antagonist might be an organization that wants to take over the Hidden Leaf Village. They see Naruto as a major obstacle because of his strength and influence among the villagers. So, they devise a plan to make everyone in the village betray Naruto. They use mind - control techniques or spread misinformation on a large scale to achieve their goal. This way, they can weaken the village from within before making their move to take it over.

There could be an ancient evil spirit that has a vendetta against griffins. When it senses that Cousland has befriended a griffin, it targets them both, trying to destroy their new - found bond and cause chaos in the world they inhabit.