Another plot could involve a magical artifact that has the power to destroy both the wizarding world of Harry Potter and the supernatural world of the Dresden Files. Harry Potter and Dresden have to race against time and different factions from both worlds who either want to use the artifact for their own gain or destroy it before it causes chaos. They would have to combine their knowledge and skills to overcome the challenges.
One idea could be that Harry Potter accidentally travels to the world of the Dresden Files. He could meet Harry Dresden and they team up to fight a dark magic threat that is affecting both their worlds. Maybe a powerful dark wizard from the Potterverse has found a way to use the magic from the Dresden Files world to enhance their power.
One idea could be that Dresden is called to Hogwarts to help solve a mystery that the wizarding world's magic can't handle alone. Maybe it has something to do with a dark magic that is tied to the Muggle world in a way the wizards don't understand. Another plot could involve Harry Potter and his friends getting lost in the Dresden Files' version of Chicago and having to team up with Dresden to find their way back to their own world while also dealing with the various threats in the new environment. A third idea is that a powerful magical artifact from the Harry Potter universe somehow ends up in the hands of a villain in the Dresden Files world, and Dresden and Harry have to work together to retrieve it before it causes chaos.
One interesting crossover could be the use of magic systems. In the Dresden Files, magic is more gritty and has a cost, while in Harry Potter it's more structured. A fanfiction might explore what happens when a wizard from Harry Potter's world tries to use Dresden Files magic, or vice versa.
One interesting 'Harry Potter Dresden Files' fan fiction could be one that combines the magic systems of both. For example, a story where Harry Potter and his friends encounter a problem that can only be solved by using Dresden's more gritty and street - wise approach to magic. Maybe they have to deal with a dark wizard who is using a blend of muggle - influenced dark magic that is more in line with the Dresden Files universe.
One idea could be a fanfic where a new character with a unique magical ability arrives in Chicago and has to team up with Harry Dresden. This new character could have an ability that even Harry has never seen before, like the power to manipulate time in small bursts, which causes all sorts of chaos and new challenges for them to face.
He could bring some of his unique spells from Hogwarts. His Patronus charm could be a very useful tool in the often - dark and dangerous Dresden Files world. It could help him fight off some of the nastier creatures there. On the other hand, the wizards in the Dresden Files might view him with suspicion at first, not knowing exactly where his loyalties lie.
One idea could be that the Grimm creatures start to appear in the wizarding world. Harry and his friends have to use both magic and knowledge of Grimm lore to fight them. For example, they might discover that some dark magic has opened a portal between the two universes.
One idea could be that the Order of the Phoenix teams up with the Kingsman. The wizards could use some of the Kingsman's high - tech gadgets and fighting skills, while the Kingsman could learn about magic. For example, Harry Potter could be trained by a Kingsman agent in hand - to - hand combat, which would give him an edge in battles against Death Eaters. Another plot could involve a villain who is a hybrid of a dark wizard and a criminal mastermind that the Kingsman usually deal with. The two groups would have to combine their resources to stop this new threat.
Maybe some of the Hogwarts students are sent to the Naruto universe. They would be amazed by the ninja techniques. Hermione, for instance, would be eager to study how chakra works and might even find a way to combine it with magic. Harry could learn some ninja stealth skills which would be useful in his fight against Voldemort.
One idea could be that the Hogwarts students discover Halo technology. Maybe Harry and his friends find a crashed UNSC ship and start to study its advanced weaponry and shields. They could try to adapt the technology to defend Hogwarts from Voldemort. Another plot could involve Master Chief being sent to the wizarding world by accident. He then has to navigate the strange new world of magic while also dealing with threats that his usual Halo combat skills might not be fully equipped for.
In a crossover, Merida could teach the Hogwarts students about her own form of magic, like the spells she uses for her archery and how she communicates with the animals in her world. At the same time, she could learn about the complex spells and potions of the wizarding world. This exchange of knowledge could lead to some exciting adventures, like using a combination of both types of magic to defeat a common enemy.