Lincoln is often a main focus. Since he's the only boy in a large family, he might take on a leadership role when the house is left in the dark. He could be the one coming up with plans to keep everyone safe and calm.
Luna could also be a main character in such fanfiction. Her wild and creative personality might shine in the dark. She could use her music to lighten the mood or even use her guitar as a tool to help in some way, like making noise to scare away imaginary threats.
Sometimes, even the family pets or the neighbors can be focused on in fanfictions related to this episode. They could be the ones who help Lincoln figure out what's really going on with his bad luck or they could be affected by his luck in some comical ways.
Obviously, the Loud family members would be the main characters. Lincoln, being the main character in the original series, would probably play a crucial role in this fanfiction too. He might be the one to come up with plans to deal with the situation of being left in the dark.
The Trix also get a lot of attention. Since they are the main antagonists in the original Winx Club, in fanfiction they can be made even more menacing. Their backstories might be explored more deeply, like how they became so dark and what their ultimate goals are. They could be involved in a plot to take over the entire Magic Dimension in a more complex and devious way than in the show.
Lincoln is often a central character. Since he's the middle child, he usually gets caught in the middle of things and is in a good position to be involved in getting or spreading the message. He might be the one trying to make sense of a confusing message or passing on important information to his sisters.
Well, in the fanfiction, perhaps the Loud family could face a power outage and have to rely on each other in new ways. They might discover hidden talents for dealing with the dark, like Lincoln using his leadership skills to keep everyone calm.
Lucy is another character that could be prominently featured. Given her gothic nature, she might have an initial attraction or understanding of the dark arts. She could either be a novice trying to learn more or a bit of an expert guiding the other Loud siblings when they encounter dark arts - related situations.
Obviously Naruto is the main focus most of the time. But other characters like Sasuke can also be important. Sasuke's own dark past and his relationship with Naruto can be further explored in a 'dark' context. For example, they might become rivals in a more extreme and less friendly way.
One possible plotline could be the Loud family having to deal with a power outage in a really creative way. Maybe they discover hidden passages in the house while searching for candles in the dark.
Well, of course, Lincoln Loud would be one of the main characters. He's the central figure in the Loud family, so it makes sense for him to be the focus in this fanfiction. His sisters might also be involved. For example, Lola could be competing with Lincoln in a lemon - themed beauty pageant, adding some sibling rivalry to the story.
Iron Man is often a main focus. His genius and charisma make him a popular choice for fanfiction writers. They can explore his relationships with other Avengers, like his banter with Captain America.