Obviously, Harry would be one of the main characters. There might also be his friends like Hermione and Ron, who could either support or be skeptical of his new power.
Harry is the central character in 'Harry Controls Darkness' fanfiction. Alongside him, Hermione is likely to play an important role. She would probably be the one to research about the nature of Harry's power over darkness. Ron, too, would be there. He might be the one to provide some comical relief during the more intense moments related to Harry's new ability. There could also be new characters introduced, perhaps an old wizard who has some knowledge about this type of power and helps Harry understand it better.
Well, Harry Potter himself is surely one of the main characters as the title implies he has the power to control time. Hermione Granger is likely to be another main character. She is always by Harry's side in the original series and would be there to help him understand and manage his new time - controlling ability, perhaps with her vast knowledge and logical thinking.
Obviously, Harry Potter is one of the main characters. He is the one who has the power to control the Dursleys. And of course, the Dursleys - Vernon, Petunia and Dudley - are also main characters as they are the ones being controlled by Harry.
Obviously, Harry Potter is the main character as the title implies. He's the one with the power to control the elements. Hermione Granger and Ron Weasley would also likely be important characters. Hermione could be helping Harry research about the origin of his element - controlling ability, and Ron would be by his side in his adventures, providing support and some comic relief.
It could be an ancient evil that has been lurking in the shadows for ages. Maybe a dark spirit that was sealed away long ago and is now breaking free, and Naruto has to control the darkness within himself to fight it.
A powerful dark spirit might be the main antagonist. This spirit could sense Naruto's new ability to control darkness and see him as a threat. So it starts causing chaos in the ninja world, forcing Naruto to use his dark - controlling powers to stop it. The spirit could have the ability to possess other ninjas, making them do its bidding.
The main characters would start with Harry Potter. Then, there could be some members of the pure - blood families. For instance, Draco Malfoy could be a key character. His family's obsession with blood purity and his own complex relationship with Harry could be further explored in the context of Harry's control over blood magic. Also, characters like Neville Longbottom could be involved, perhaps his connection to his family's history through blood could be related to Harry's new power.
The main character is Harry Potter. However, other characters like Luna Lovegood could be important. Her unique perspective on the wizarding world might offer Harry new insights on how to use his reality - controlling powers. And Neville Longbottom could also be involved, perhaps using his new - found confidence to support Harry in his reality - altering adventures.
Ron would be there too. He could be in charge of things like the Gryffindor common room or helping Harry with student relations. And of course, Dumbledore might still have some influence in the background, even if Harry is in control. His wisdom could be a guiding force for Harry as he navigates running the school.
Definitely Harry Potter. He's the central figure in most Harry Potter - related stories. Alongside him, Dumbledore could be a main character, guiding Harry even from the shadows in this 'Descent into Darkness' story. And then there might be a character who is a double agent, perhaps a Slytherin student who pretends to be on the dark side but is actually helping Harry and his friends. This character could add a lot of intrigue to the plot.
The main character is the 'Heir of Darkness', who has a complex personality and backstory. Harry Potter would be a main character as he is often at the center of any major events in the Harry Potter universe. Additionally, there could be antagonists in the fanfiction related to the dark side that the heir might be associated with. For example, a group of dark wizards who want to use the heir for their own evil purposes. And the fanfiction might also introduce some minor characters from the original series in new roles, like Luna Lovegood providing some unique insights about the heir's situation.