It could be about Harry Potter somehow being transported to the Avatar world. Maybe he discovers he has bending abilities and has to learn to control them while also dealing with the political and social issues in the Avatar universe.
Another possible plot could be a merging of the two worlds. The magic from Harry Potter and the bending from Avatar combine in some way. Characters from both universes have to learn from each other and work together. There could be a new threat that only the combined powers of both worlds can defeat. This would involve a lot of character development as they adapt to new cultures and powers.
Perhaps the plot involves the Avatar coming to the Harry Potter world. The Avatar could use their bending skills to help in the fight against Voldemort. They might also introduce new forms of magic based on the elements they can bend. For example, using water bending to heal in a way that's different from regular magic in the Harry Potter series.
He might be really confused at first. Harry Potter comes from a world of magic and wizards, and the Avatar world is so different with its own unique cultures, bending abilities and spirits. He could be intrigued by the new concepts and might start comparing the magic in his world to the powers in the Avatar world described in the fanfiction.
There are also some Tumblr blogs that focus on Harry Potter fanfictions. Some bloggers curate lists of interesting crossovers. It might take some time to search through, but it could be a great source. You can use relevant tags like #HarryPotter #Avatar #Fanfiction to narrow down your search.
One possible plot could be that Harry stumbles upon the Sword of Gryffindor in a hidden chamber in the Forbidden Forest. Maybe he's on a solo quest to find a powerful weapon against Voldemort and the magic of the forest guides him to it. Then he has to figure out how to use its power to his advantage in the upcoming battles.
The snake could be an injured or lost magical creature. Harry, being the kind - hearted person he is, decides to take care of it. As he does, he realizes that the snake has a connection to a powerful wizard or witch who has been lost for ages. This connection then draws Harry into an adventure to find out what really happened to that powerful figure and how it affects the present state of the wizarding world.
Well, perhaps in this fanfiction, Harry Potter stumbles upon a lost baby in the wizarding world. He might then take it upon himself to find the baby's parents. Maybe he uses his magical skills, like casting spells to track the family. He could also seek help from his friends at Hogwarts, like Hermione who would surely be resourceful in finding clues about the baby's identity.
Well, perhaps in this fanfiction, Harry Potter stumbles upon a baby while on one of his adventures. Maybe the baby has some sort of magical power that he has to protect from the dark forces. It could also be that the baby is related to an old prophecy and Harry has to figure out how to keep it safe and fulfill the prophecy at the same time.
Well, it could be that the magic book is sentient and starts to communicate with Harry. It could offer him advice on how to defeat Voldemort in a completely new way, like revealing a long - forgotten prophecy.
Well, perhaps Harry uses his magic to sense the One Ring's power. He might initially mistake it for a dark magical artifact from his own world. Then, he could start on a journey to figure out what this strange ring is, all while facing challenges from both the wizarding world (like Voldemort's followers thinking he has a new powerful weapon) and from Middle - earth forces that are also after the ring.
The plot could be that the cat is a magical key to a hidden chamber. As a child, Harry stumbles upon the cat and realizes it has a strange mark. When he touches the mark, it reveals a map that leads him to a secret chamber filled with ancient magic and knowledge.
Perhaps Harry is transported to a different dimension where the Power Rangers exist. There, he discovers the Wolf Zord. He has to learn how to bond with it, just like the Rangers do. He could bring some of his magic skills to the table, and in turn, the Wolf Zord gives him new abilities to use against Voldemort or other foes back in his own world.