Perhaps a jealous classmate who discovers Artemis's connection to the fairy world. This classmate wants to use that knowledge to gain power and popularity, so they start causing trouble for Artemis and his friends, trying to expose them to the wrong people or get in the way of their fairy - related investigations.
One idea could be Artemis starting a secret club at high school to study ancient languages and artifacts, leading to unexpected adventures. Maybe he discovers a hidden code in a school text that links to a mythical treasure.
A power - hungry fairy could be the main antagonist. This fairy might see Artemis as an upstart and a threat to their own position in the fairy hierarchy. They could try to undermine Artemis at every turn, setting up traps and spreading false rumors about him in the fairy world.
Another fanfic could focus on their relationship development. Maybe they start off as rivals in a competition of wits at a prestigious academy. As they face various challenges together, they gradually realize their respect for each other turns into something more, like friendship or even a budding romance.
It could be a new demigod who has turned to the dark side. Jealous of Percy's popularity and Artemis' power, this demigod could try to create chaos in the high school and turn students against them.
One interesting plot could be exploring his dad's early adventures in the criminal underworld before Artemis was born. Maybe he was on a secret mission to retrieve a powerful magical artifact that was lost for centuries.
Another interesting fanfic could be about Artemis and Holly having a falling out due to a misunderstanding. The story could then revolve around how they eventually come to understand each other again and reconcile. This could involve them facing their own personal demons and insecurities along the way.
Loki could be a great main antagonist. He could be the mischievous student who's always causing trouble for the Avengers. He might use his magic to play pranks on them or steal their homework to make them look bad in front of the teachers.
It could be a jealous classmate. Maybe someone who has a crush on Armin and sees Annie as a threat to their relationship. This person could try to spread rumors about Annie to make Armin stay away from her.
Artemis Fowl is the central character, a brilliant and somewhat conniving young boy. Another important character is Holly Short, an elf in the fairy world. She is a strong and capable female character. There is also Butler, Artemis's loyal bodyguard. He is highly skilled in combat and protecting Artemis. These characters play crucial roles in the story, with their interactions driving the plot forward.
The main plot involves Artemis Fowl, a young criminal mastermind. He discovers the existence of a hidden world of fairies. He then tries to steal fairy gold for his family's fortune by outwitting the fairies with his high intelligence and elaborate plans.