Often, Harry Potter himself is a main character. Since it's related to the Harry Potter universe, he is likely to be involved in the story centered around the millenium puzzle.
Another possible main character could be a new, original character created specifically for this fanfiction. This character might have a special connection to the millenium puzzle, like being a descendant of the wizard who created it. They could bring a fresh perspective to the story and interact with the well - known Harry Potter characters in unique ways.
Hermione Granger might also be a main character. Her intelligence and thirst for knowledge would make her a great candidate to be involved in solving the mystery of the millenium puzzle. She could use her research skills to uncover clues about its origin and purpose.
One interesting idea could be a new magical creature introduced through the millenium puzzle. It might be a creature that holds the key to an ancient mystery in the Harry Potter world.
The Marauders, James Potter, Sirius Black, Remus Lupin, and Peter Pettigrew, are still popular in Harry Potter millenium fanfiction. Writers often explore their time at Hogwarts in the past within the context of how it affects the millennium. For example, a story could be about a hidden secret they left behind that resurfaces in the new millennium. Albus Dumbledore also remains a prominent figure in many fanfictions. His wisdom and the mystery surrounding his past are often delved into, especially in relation to the changes and events that occur in the millennium within the wizarding world.
Well, one plot twist could be that Naruto's ability to solve the Millenium Puzzle unlocks a hidden power within him that's different from the Nine - Tails chakra. Maybe it gives him the power to time - travel, and he has to use this new power to prevent a great disaster in the ninja world that was foreseen by the ancient spirits connected to the Millenium Puzzle.
One interesting 'Harry Potter millenium fanfiction' story could be about how the wizarding world adapts to the new millennium. For example, they might have to deal with new forms of magic that are emerging due to the change in the era. Another could be a story where Harry Potter's children face a new threat that is related to the millennium and the ancient prophecies. There could also be fanfictions that explore how Hogwarts itself changes over time with the new millennium, like new courses being introduced or new areas of the castle being discovered.
They could use magic spells to calm the dragon first. For example, the 'Diffindo' spell might be used to cut ropes that are binding the dragon in an aggressive way, showing the dragon that they mean no harm. Then, they can start communicating with it using Parseltongue if they have that ability, like Harry does. Maybe the dragon has some knowledge about the puzzle and can give hints if it trusts the characters.
Since I don't know the exact 'star puzzle story', it's hard to say. But it could be a young adventurer, someone brave and curious enough to take on the challenge of the star puzzle.
I'm not sure exactly as I haven't read it, but it might feature characters like Lisbeth Salander if it's related to the Millenium Series. She is a very well - known character from the series.
Harry Potter is the mainstay, as the story is based in the Harry Potter universe. Kurama is the new element that makes it a crossover. In addition, characters like Snape could play significant roles. Snape's complex nature might lead to interesting interactions with Kurama. He could be initially hostile but then come to realize Kurama's value in the fight against the dark side. And of course, Hagrid, with his love for magical creatures, might befriend Kurama and help him adjust to the wizarding world.
Hermione Granger might also be a main character. She is an important part of the original series and her intelligence and knowledge would be useful in uncovering any truths in this fanfiction. Also, Ron Weasley could be there as Harry's loyal friend, and together they could face the challenges related to the 'truth' in the story.
Most likely Harry Potter himself would be one of the main characters. After all, it's in the title related to the Harry Potter world. And of course, the ogre would be a main character too as it's a key part of the fanfiction.