One way to blend the two universes is through the use of magical artifacts and Cybertronian technology. Maybe the Philosopher's Stone could be used to power up Optimus Prime in some way, or a Cybertronian device could be used to enhance a wizard's magic. This creates a connection between the two universes where they rely on each other's unique elements.
Well, it blends them by combining the magic of the Harry Potter universe with the superpowers of Superboy. For instance, in such fanfiction, Superboy might have to deal with the laws of magic which are completely different from what he's used to in his own world. His super strength might be affected by anti - magic spells, or his flight ability could be disrupted by magical fields.
Well, it often has Harry using Hitman - like skills. For example, stealth and precise attacks. In some fanfics, he might use magic to enhance these skills. Like using a silencing charm while sneaking up on an enemy, just like a hitman would use his training to be quiet.
Fanfiction often uses crossovers to blend these two universes. It might start with a portal or some sort of magical accident that transports Ahsoka to the Harry Potter world or vice versa. Once there, the different cultures and technologies can be compared and combined. For instance, the use of lightsabers in a world full of wands can create really interesting scenarios. The fanfic writers also use the existing storylines of both universes. They might put Ahsoka in the middle of the fight against Voldemort or have Harry and his friends explore the Star Wars galaxy. This way, they can explore how the two universes would interact and what new stories could be created.
Well, it often blends the two by having characters from one universe enter the other. Like a Supernatural character might end up in the wizarding world through some sort of magical portal or spell gone wrong. Then they have to adapt to the new rules and powers there.
Typically, it might start with a crossover event like a magical portal opening between Gotham and the wizarding world. Then characters from both sides interact. For example, Damian Wayne could end up at Hogwarts and his combat skills and detective instincts would be a contrast to the magic - based skills of the Hogwarts students like Harry Potter.
In fanfiction, the two universes blend in multiple ways. The characters from Harry Potter can be put into Creepypasta - like situations. For instance, Harry might find himself in a situation where he has to face a entity that is not from the wizarding world but from a Creepypasta realm and has to use his magic in a new and untested way to survive. Also, the magic in Harry Potter can be warped to fit the spooky nature of Creepypasta. Spells could have unexpected and disturbing side - effects that are more in line with Creepypasta. The creatures in Harry Potter can also be made more menacing by borrowing elements from Creepypasta. For example, a Hippogriff could be made to look more like a nightmarish beast with Creepypasta - inspired features.
One way is to establish a shared threat. Let's say there's a being that can travel between the two universes and is causing chaos in both. This forces the characters from Harry Potter and The Doctor to work together. In terms of world - building, describe how the different magics and technologies interact. For instance, the Time - Lords' time - travel abilities could be compared and contrasted with the time - turners in Harry Potter. The characters from both sides need to have believable reactions to the new elements of the other universe. Harry might be awestruck by the TARDIS, while the Doctor could be intrigued by the magic spells at Hogwarts.
The blend occurs through character adaptation. For instance, the characters from Harry Potter might adopt some of the attitudes and behaviors of gangsta characters. Hermione could be like the brains behind a gang's operations, using her vast knowledge in a more street - wise way. And the story might be set in a more urban, gritty environment which is typical of the gangsta genre while still having the magic of Harry Potter.
In these fanfictions, they blend by sharing certain characteristics. For example, the loyalty and camaraderie among the characters in both universes are emphasized. In Harry Potter, it's the loyalty among the students of Hogwarts and the Order of Phoenix. In Kancolle, it's the bond between the shipgirls. This common trait can be a basis for the two universes to interact, like the shipgirls and the wizards/witches working together based on mutual trust.
One way is through the use of magic and advanced technology. For example, Guinan's knowledge of time - travel technology could be combined with the time - turning magic in the Harry Potter universe. This would create really interesting plotlines.