In this type of fanfiction, the concept of identity is really fascinating. The dark twin forces Harry to question who he really is. Is he the heroic Gryffindor we know from the books, or does the presence of the dark twin mean there's more Slytherin - like cunning in him? The relationship between Harry and his friends might also change. His friends may initially be confused or even afraid of the changes they see in him due to the influence of the dark twin. And the Hogwarts environment itself could be portrayed differently as the dark twin's presence might disrupt the normal order of things at the school.
One interesting concept could be the shared experiences between Harry and his twin. They might have a unique connection that allows them to sense each other's emotions or thoughts, even from a distance. For example, if one is in danger, the other might feel an unexplained sense of unease.
One interesting concept could be the combination of magic from Harry Potter and the challenging combat and dark atmosphere of Dark Souls. For example, a fanfic might explore how a Hogwarts student would fare in the Dark Souls world, having to rely on both their spells and newfound combat skills. Maybe they'd use the levitation charm to avoid dangerous terrain or use protego against some of the deadly attacks in Dark Souls.
Well, one interesting concept could be the unique backstories of the original characters (OCs). These OCs often have complex pasts that tie into the dark elements of the Harry Potter universe. For example, an OC might be a descendant of a dark wizard family trying to redeem themselves or a Muggleborn with a dark secret related to the wizarding world.
Well, one interesting concept could be the exploration of darker magic in a more in - depth way than in the original series. For example, it might show how certain spells that were only hinted at in the books as dark could be fully utilized and the consequences that follow. Another concept could be the different interpretations of characters' personalities when exposed to the 'Dark Echo'. Some fanfictions might show a more conflicted Harry Potter, torn between the light he was raised with and the allure of this new, darker side of magic.
In some fanfiction, dark rituals might involve dark magic objects. For example, the use of the Resurrection Stone in a way that goes against the natural order. It could be used to bring back a powerful dark wizard who was once defeated, creating chaos in the wizarding world.
One interesting concept could be the fusion of the magical world of Harry Potter with the Keyblade concept from Kingdom Hearts. It might involve creating new spells or powers related to the Keyblade within the Hogwarts setting. For example, a character could use a Keyblade to unlock hidden chambers or secrets in the castle that are otherwise inaccessible. Another concept could be the idea of a dark Keyblade wielder in the Harry Potter universe who uses the power for evil, perhaps to take over the Ministry of Magic or to control the Dementors.
The dark shadows in some Harry Potter fanfiction might represent the hidden, dark side of Hogwarts itself. There could be secret passages and rooms that are filled with 'dark shadows' both literally and metaphorically. These areas might hold secrets about the founders or dark magic that was once practiced within the school walls. It could add a sense of mystery and danger to the familiar Hogwarts setting.
Well, in 'Harry Potter goes dark fanfiction', a common concept is the alteration of the wizarding world's power structure. Maybe Voldemort wins in a different way and Harry has to survive in a much harsher, more tyrannical regime. Or perhaps Harry himself becomes a sort of anti - hero, using the dark side of magic to fight against what he perceives as a greater evil, even if it means sacrificing some of his principles. And there could be the idea of dark magical creatures being used as weapons instead of just threats in the background.
In some 'Harry Potter Dark Lady fanfiction', the Dark Lady might be a character who has a complex backstory. Maybe she was once a good witch who was wronged and turned to the dark side. This would add depth to the character and make the story more engaging as we see her transformation.
One interesting concept could be exploring the characters' hidden emotions. In fanfiction, authors often delve deeper into the psyche of the characters from the original work. For example, they might show a character's fear of the dark in a more profound way, which wasn't fully explored in the original. Another concept could be the creation of new relationships. Fanfiction writers might pair characters in unexpected ways within the 'in the dark' setting, adding a new dimension to the story.