Coach Hedge could be a great character to focus on. He's not always in the spotlight but he has a lot of potential. In fanfiction, we could see his life before he became a coach at Camp Half - Blood, his own adventures as a satyr, and how he really feels about the demigods he's supposed to protect. There could be a story where he has to use his satyr skills in a new and unexpected way to save the day during an event related to 'Blood of Olympus'.
Nico di Angelo is often overlooked compared to Percy. He has such a rich backstory with his connection to the Underworld and his struggle with his identity. Fanfiction could explore more of his inner thoughts and his relationships, especially his friendship with Percy on a deeper level.
Reyna is another underrated character. She's a strong and capable leader. In fanfiction, her past experiences in Camp Jupiter and her relationship with the Roman gods could be delved into more. Maybe she could have her own solo adventure that ties into the events of 'Blood of Olympus' but gives her more spotlight.
Reyna is another one. She's a strong and independent leader. Fanfiction could focus more on her past, her time leading the Roman camp, and how she copes with the different challenges she faces, especially when it comes to interacting with the Greek demigods.
Nico di Angelo is often underrated. He has such a complex backstory with his relationship to the Underworld and his struggle with his identity. In fanfiction, you could really explore his internal battles more deeply. Another one is Tyson. He's a cyclops and Percy's half - brother, but he doesn't always get as much attention as he could. You could write about his experiences at Camp Half - Blood and how he overcomes the prejudice some of the other campers have towards him.
Silena Beauregard is also underrated. She could be the focus in a fanfiction set in the school. Since she was a daughter of Aphrodite, she could use her charm and beauty skills in a different context at school. For example, she could use her powers to boost the confidence of shy students or mediate between feuding groups by using her charm to calm everyone down.
Silena Beauregard is an underrated character. In fanfiction, she could be given more backstory and more involvement in the main plot. Maybe she could be brought back in some magical way and have a new role to play in the fight against the forces of evil. Also, the Stoll brothers, Travis and Connor. They are often just used for comic relief, but they could be developed into more serious characters in fanfiction. They are sons of Hermes, so they could have some really interesting stealth and thieving - related adventures that could tie into the main story.
There's also Grover. He's Percy's best friend, but in a lot of fanfiction, he's just there as a sidekick. He could be developed more, like showing his growth as a satyr and his role in protecting nature. And then there's Clarisse. She's a tough and strong demigod, but often overlooked. Fanfiction could explore her in - depth feelings and her own quests that are separate from Percy's.
Some of the minor prisoners who are not the main villains in the original Blood Prison story could be interesting. Maybe a prisoner who was just in the wrong place at the wrong time and has some unique abilities that could be developed further in the fanfiction.
Percy Jackson and Annabeth Chase are definitely popular choices. Their relationship and their individual heroics are well - loved by fans. Another popular character is Nico di Angelo. His dark and mysterious nature makes for great fanfiction material.
The old hermit character. He was only in a few scenes but seemed to know a lot. Fanfiction could explore his past and how he came to have his knowledge. There's also the young apprentice who was often overlooked. He might have some hidden powers or a special connection to the treasures that could be delved into.
One underrated character is Baltus Van Tassel. He's Katrina's father and has a big role in the town. Fanfiction could explore his backstory, like how he came to be such an important figure in Sleepy Hollow. Maybe he had some adventures in his youth that are related to the Horseman legend. Another is the schoolmaster before Ichabod Crane. What was his experience in Sleepy Hollow? What did he know about the Horseman that he might have passed on to Ichabod? And then there's the old woman who lives on the outskirts of town. She might seem like a minor character, but she could be a seer or have some connection to the supernatural forces in Sleepy Hollow.
Rock Lee is often overlooked compared to the main characters. A fanfiction could focus on his journey to become an even greater ninja without relying on ninjutsu. Another underrated character is Shino Aburame. His unique bug - related abilities could be explored more deeply in a fanfiction, like how he might use them in different and unexpected ways.