Loki and Zuko could be main characters in such a fanfic. Zuko has his own journey of redemption and Loki has his own complex past. They could bond over their struggles with identity and family. Zuko's firebending skills would also be an interesting contrast to Loki's magic. They could either become enemies or form an unexpected friendship as they navigate the challenges in a world that combines the elements of Asgard and the Avatar universe.
One interesting concept could be the merging of Loki's mischievous and complex personality with the unique world - building of Avatar. For example, Loki might find himself in the midst of the elemental bending cultures and cause all sorts of chaos and intrigue. Maybe he'd try to manipulate the different tribes for his own gain, or perhaps he'd be intrigued by the spiritual connection to nature in Avatar and it would change his own views on power and control.
Aang could be a great crossover character. Since he is from the previous Avatar cycle, his different approach to bending and his more laid - back personality compared to Korra could create interesting interactions. He could offer her wisdom from his own experiences as an Avatar.
There's also 'When Pandora Meets Aiur'. In this fanfic, the Na'vi from Pandora and the Protoss from Aiur come into contact. The Protoss are intrigued by the Na'vi's harmonious relationship with their planet, while the Na'vi are in awe of the Protoss' advanced technology. It delves deep into the cultural exchanges and potential conflicts that could arise between these two very different species.
One possibility could be the characters from 'Avatar' and 'The Dragon Prince' meeting and having to team up to face a common threat. Maybe the bending powers from 'Avatar' and the magic in 'The Dragon Prince' could combine in interesting ways. For example, a waterbender could work with a Moonshadow elf, using their respective powers of water and shadow to outwit their enemies.
In a battle situation, the interactions would be really exciting. The Voltron team is used to working together in their lions, but in the Avatar world, they would have to adapt to fighting alongside benders. Lance might team up with a firebender and use his sharpshooting skills along with the firebender's attacks. The Avatar could also be in the middle, using their all - four - element powers to support both the benders and the Voltron pilots.
One idea could be to have the Voltron pilots end up in the Avatar world. They could learn bending techniques and use their Voltron skills in combination with them. For example, Keith's swordsmanship might blend well with waterbending moves in a fight.
Another possibility is a crossover of the settings. The Camp Half - Blood could be merged with an area from the Avatar world, like the Air Temple. Demigods and benders would have to learn to co - exist and use their powers together. Maybe Percy could learn water - bending techniques from the water benders to enhance his control over water, which is already one of his powers. And the Avatar could learn about the Greek gods and use that knowledge to gain an edge in his battles.
The plot might involve a magical mix - up. Maybe the power - granting items in The Seven Deadly Sins world, like the Sacred Treasures, get scattered across the Avatar world. The characters from both series then have to search for these items. The Avatar characters with their bending abilities and the Sins with their unique powers would have different approaches to finding the treasures. This could lead to a lot of interesting interactions and conflicts.
One interesting storyline could be the Na'vi from Avatar using their unique connection with nature against the Zerg in Starcraft. The Na'vi's ability to communicate with animals and their natural combat skills might create an unexpected dynamic when facing the swarming Zerg. Another could involve the Protoss sharing their advanced technology with the humans in the Avatar universe. This could lead to new forms of exploration and resource management. And a third might be a story where the Terrans from Starcraft get stranded in the Pandora planet of Avatar and have to adapt to the local environment and deal with the native species while also trying to find a way back home.