In a fanfic, the integration could start with a character from the Dark Angel world being curious about the magic in the Harry Potter universe. This Dark Angel character could disguise themselves as a student at Hogwarts. As they interact with the students and teachers, like Harry Potter, Hermione, and Dumbledore, they learn about the different types of magic. Meanwhile, the Hogwarts characters start to notice that this new student has some very strange and powerful abilities. Eventually, they discover the truth about the Dark Angel character, and together they embark on a journey to explore the connection between their two worlds and face any threats that might come from it.
One way to integrate them is to have a common enemy. Let's say there is a new, powerful dark force that threatens both the wizarding world and the Dark Angel world. Characters from both would then come together. Harry Potter, with his knowledge of magic, and the Dark Angel characters, with their unique powers, could combine their skills to fight this enemy. Also, a prophecy could be involved that foretells the coming together of these different beings to save all of existence. And in the process of working towards this goal, they learn about each other's cultures and abilities.
The characters can be integrated through a magical accident. For example, a spell gone wrong could open a portal between the two universes, allowing characters like Harry Potter to meet the Dark Angel characters. They could then form alliances or rivalries based on their different abilities and goals.
One way is to use it as a gift. For example, a character could give dark chocolate to another as a sign of friendship or apology, just like how chocolate is often used in the original series. Another way is to make it part of a potion ingredient. It could add a unique flavor or property to the potion.
One way is to make them a part of a Hogwarts mystery. For instance, a Gorgon could be the key to solving a centuries - old riddle hidden within the castle walls. Their stone - turning power might be related to a secret passage or a hidden treasure that only they can access.
They can be integrated through crossovers. For example, Harry could end up in Gotham due to a magical accident and team up with Batman. Their different skills would complement each other. Harry with his magic and Batman with his combat and detective skills.
Merlin could be integrated as a forgotten ancestor of one of the main characters. For example, if he was an ancestor of Hermione, it could explain her extraordinary intelligence and affinity for magic.
It could be introduced as a result of a failed experiment by a dark arts practitioner. For example, a Death Eater tries to create a powerful creature to use against Harry, but the chimera has its own will and doesn't want to be used for evil. So it escapes and finds its way to Harry, who then has to deal with this new and dangerous but also potentially helpful being.
Ghouls can also be used to create conflict. Imagine a fanfic where a group of dark wizards are trying to control the ghouls to use them as weapons against Hogwarts. The students and teachers then have to find a way to stop the dark wizards and free the ghouls from their control.
One way is through a magical accident. For example, a spell gone wrong could transport Cersei into the Harry Potter universe. Then she'd have to interact with the characters there. Maybe she'd initially see them as weak but soon realize the power of magic.
The magic in Harry Potter could be seen as a different form of chakra. Spells could be chakra - based techniques. For instance, the levitation charm could be a chakra technique that Naruto or other ninjas learn. It could be used in combat or just for everyday tasks like moving heavy objects.
I'm not familiar with the exact details of this fanfiction, but typically in a Harry Potter - based fanfiction with a 'rise of the dark angel' theme, Harry Potter himself would be a main character as he is the hero of the original story. The 'dark angel' would be another crucial character. There might also be other characters from Hogwarts like Dumbledore, who would oppose the rise of the dark angel. Maybe some new characters created specifically for this fanfiction would also play important roles, perhaps characters who are related to the origin or the power source of the dark angel.
The original Harry Potter stories are family - friendly and aimed at a wide audience. They have a clear narrative arc of Harry's fight against Voldemort and the triumph of good. 'Dark Harry Potter fanfic', on the other hand, can be much more complex and edgy. It may explore themes like the allure of the Dark Arts, the corrupting influence of power, and a more nuanced view of the wizarding world. For instance, it could show how the Ministry of Magic might be even more corrupt than we thought in the original, and Harry has to deal with that in a very different way than in the books.