A dragon - tamer from a nomadic magic tribe. This character could have grown up around dragons and have a deep understanding of their behavior. They could be a wild card in the tournament, not really following the traditional Hogwarts ways of dealing with dragons and bringing a fresh perspective.
An old ex - Auror who now lives near Hogwarts. He could have a past connection to Voldemort and some knowledge about the Dark Arts used in the Triwizard Tournament. He becomes an unofficial mentor to Harry, teaching him some unique spells and strategies that are not part of the regular Hogwarts curriculum. This character could bring a new perspective and a bit of wisdom to the story.
A wizard from a far - off land, like a wizard from a hidden tribe in the Amazon rainforest. He or she could bring a completely different style of magic that the Hogwarts students and other champions have never seen. Their magic could be more nature - based, using the power of the rainforest plants and animals. This would make their approach to the Triwizard tasks very different and exciting.
Puar could be an interesting underdog. Although not typically a fighter, in a fanfiction, Puar could have some hidden power or develop a new technique. Maybe Puar could transform into a super - powerful creature with unique abilities that catch everyone off - guard in the Tournament of Power.
A character like a half - elf half - wizard who has a special connection to the Ravenclaw Diadem. Maybe they were born in the Forbidden Forest and their elven heritage gives them an intuition about magical artifacts. They sense the diadem's power and are drawn to Hogwarts to protect it from those who would use it for evil.
It could be a new student at Hogwarts. A young witch or wizard who has always been fascinated by dragons and finally gets the chance to encounter one and become a rider. This character could bring a fresh perspective to the Hogwarts world.
Luna Lovegood could be an interesting choice. She has a very unique view of the wizarding world. As a DADA teacher, she would teach in her own offbeat way. For example, she might introduce the students to the idea of defending against invisible creatures that most wizards don't believe in. Her lessons would be full of creativity and would make the students think outside the box.
A young Auror who is assigned to help guard Azkaban but has a secret sympathy for the prisoners. This character could add a new dynamic to the story as they struggle between their duty and their conscience.
It could be an original character created specifically for this fanfiction. Maybe a young wizard or witch who has always been an outcast in the wizarding world and discovers their unique ability to connect with dark dragons.
Hermione could help. She's very smart and could research about the dragon's weaknesses.
A young dragon tamer from a far - off land could be an interesting addition. This character could have a deep understanding of dragons and offer Harry some advice on how to approach the task. Maybe they have a special bond with one of the dragons in the task and can communicate with it, which could add an unexpected twist to the story.