One idea could be a crossover where Ben 10's Omnitrix malfunctions near Avatar Aang's world. Ben and Aang team up to face a new threat that is causing chaos in both their realms. Maybe some of Ben's alien forms have unexpected interactions with the bending abilities in the Avatar world.
In a fanfiction, the Avatar State of Aang could be used in a more creative way. For example, Aang accidentally enters the Avatar State during a cultural festival. His friends are initially worried, but then they realize that in this state, Aang can communicate with the spirits present at the festival in a unique way. He learns secrets about the spirits and their connection to the human world, which he then uses to strengthen the bond between the two realms when he's out of the Avatar State.
Another fanfiction could explore the challenges they face during Katara's pregnancy. Since Aang is the Avatar, he has many responsibilities. There could be a conflict where he has to leave for an important mission, but he doesn't want to leave Katara alone. Katara, being strong - willed, tells him to go and fulfill his duties. In his absence, she discovers new water - bending techniques related to pregnancy and childbirth, which she plans to teach other women in their community later.
One common theme is friendship. Since Aang is a central character, the stories often explore how he forms a deep friendship with the female avatar. They support each other, learn from one another, and grow together.
They are popular because Aang is such a beloved character. His death in a fanfic creates a lot of drama and allows for exploration of different characters' emotions. Fans like to see how the other characters would react and grow in the face of such a great loss.
Well, a common theme in fanfiction is their romantic adventures. Fanfic writers love to imagine Aang and Katara going on secret dates to beautiful, hidden places. These could be secluded islands or magical caves. Their relationship in fanfiction can also be a bit more complex than in the original series. There could be misunderstandings due to their different upbringings. Aang being the last Airbender with a more carefree nature at times, and Katara being a strong - willed Water Tribe girl.
One great Aang fanfic is 'Aang's New Adventure'. It takes place right after the end of the series. In this fanfic, Aang has to deal with some leftover Fire Nation rebels who don't want to accept the new peace. It's really exciting as it shows Aang using his bending skills in new and creative ways to bring about peace once again.
In the 'Avatar: The Last Airbender' series, there are no real love stories between Azula and Aang. Azula is a complex antagonist, while Aang is the heroic Avatar. Their relationship is mainly one of opposition, with Azula constantly trying to thwart Aang's mission to save the world.
One possible 'Avatar Aang death fanfic' could be about how his friends deal with the grief. For example, Katara might struggle with the loss of her love while also having to step up and be a stronger leader in the Water Tribe. Another could focus on how the world changes without Aang's presence to maintain balance. Maybe new benders emerge in unexpected ways to fill the void he left.
A good plot twist could be that while in the Avatar State, Aang is possessed by an ancient and malevolent spirit. His friends have to find a way to break the possession without harming Aang. This would create a lot of tension and force them to seek help from unlikely sources, like an old hermit who knows ancient spirit - binding techniques.