There's also 'Percy and Thalia: The Hidden Past'. This one uncovers some secrets from their past that they didn't even know about themselves. It's a long read but well worth it as it adds a whole new layer to their relationship.
A good Percy Jackson x Thalia fanfic should stay true to their characters. Thalia is strong - willed and Percy is brave, and these traits need to be shown in the story. For example, in a well - written fanfic, they might argue about a battle strategy because of their different approaches.
One common theme is friendship. Since they are both part of the same world of demigods, their friendship is often explored, like how they support each other through tough times. For example, in many fanfics, they help each other deal with the pressures of being a demigod.
I really like 'Percy and Thalia's Adventure'. In this fanfic, they go on a quest together that was not part of the original books. The author does a wonderful job of capturing their personalities. Thalia's fierce and independent nature and Percy's loyalty are shown really well throughout the story.
There's also 'Thunder and Sea'. In this fanfic, the author explores their connection against the backdrop of the ongoing battles in the Percy Jackson universe. It's a great read if you like action - packed fanfics with a touch of romance.
The Hunters of Artemis could be a great addition. Since Thalia was once a part of them, it would be interesting to see how she interacts with them again, especially in the context of her relationship with Percy. Zoe Nightshade, if brought back in some way, could be a very cool character to include. She has a strong personality and a tragic backstory. Also, Clarisse La Rue could be in the story. Her tough - as - nails attitude and her rivalry with Percy could spice things up, especially when it comes to the relationship between Percy and Thalia.
There's a fanfic called 'Thalia and Percy's Adventures Beyond Camp'. In this one, they team up to go on a quest outside of Camp Half - Blood. The author does a wonderful job of capturing their personalities. Thalia's tough and independent nature combined with Percy's loyalty and humor makes for an engaging read. The story also features some interesting new mythological creatures that they have to face together.
One great 'Percy Jackson x Thalia Grace fanfic' is 'Under the Stars'. It really delves into their relationship in a very interesting way. It shows how their different personalities, Percy's more laid - back nature and Thalia's strong - willed character, interact and create a unique dynamic.
First, study the characters well. Know Percy's loyalty and Thalia's fierceness. Then, come up with a unique plot. Maybe it could be a new adventure that forces them to work closely together.
Yes, there are quite a few great ones. You can start by looking on popular fanfiction websites like Archive of Our Own. Some fanfictions might focus on their adventures together, while others could explore a potential romantic relationship between them.