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.
One common theme is power control. Aang often has to learn how to handle the immense power of the Avatar State without losing himself. For example, in many fanfictions, he struggles with the sudden influx of energy and the potential for destruction it holds.
Well, 'The Mystery of Aang's Avatar State' is also a good one. In this fanfiction, Aang discovers some long - forgotten secrets about the Avatar State. It has a lot of character development for Aang as he explores the true nature of this powerful state and how it can be used for the greater good.
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.
One key event was when Aang first discovered Yakone's bloodbending crimes. Another was their face - to - face confrontation where Yakone tried to use his bloodbending on Aang. And finally, Aang's victory in the Avatar state.
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.
Katara would probably be very worried about Aang, biting her nails and constantly on the edge of her seat. Sokka might be making comments about Aang's fighting style, sometimes joking but also being in awe. Toph would be 'watching' in her own way, feeling the vibrations of the fight and being impressed by Aang's power.
Well, one exciting moment could be when Aang first enters the Avatar State during the fight. It's a powerful display of his connection to the spiritual world. Another might be when he uses a new and unexpected bending move against Ozai, catching everyone off - guard.
One great Aang fanfic could be one where he has to face an unexpected new threat in the Spirit World. It might explore his growth as the Avatar even further, showing his unique connection to the spirits and how he uses airbending in creative ways to overcome challenges.
Yes, there are quite a few interesting 'Avatar Aang and Katara' fanfictions out there. You can start by looking on popular fanfiction websites like Archive of Our Own. Some fanfictions explore their relationship further after the events of the show, delving into their daily lives and how they grow together.