Some fanfics use the idea of a common enemy. There's this one where an ancient evil is threatening both the demigod world of Percy Jackson and the superhero world of Young Justice. The female Percy, with her unique powers and knowledge, teams up with the Young Justice heroes. This way, the two universes are brought together as they fight against the same foe.
Well, in many fanfics, they merge the universes by having some sort of magical or scientific accident. For example, in one fanfic, a portal opened up between Camp Half - Blood and the Young Justice headquarters. The female Percy Jackson then gets sucked into the Young Justice world and has to adapt.
Another way is when a character from one universe is sent to the other on a quest. Let's say Percy Jackson is sent to the Naruto world to retrieve an object that has somehow ended up there. His presence then starts to mix the two universes as he befriends the ninjas and they learn about his world.
Some fanfictions use a device or an ancient artifact as the means of merging the universes. It could be a powerful crystal that has the ability to connect different dimensions. Once this item is activated, it starts to bring elements of the Voltron and Young Justice universes together, causing characters to meet and stories to intertwine.
Well, in fanfiction, it could also be that there is a common enemy. For example, a powerful ancient being that is a threat to both the demigod world of Percy Jackson and the world that Agents of Shield operates in. This would force them to team up. Percy's powers like controlling water could be really useful in some of the situations that Agents of Shield faces, like dealing with underwater threats or putting out fires in a unique way.
Writers often start by establishing how a fem Percy Jackson could end up in the Harry Potter universe. Maybe through a magical portal or some kind of cross - dimensional spell. Then they find ways to make her demigod powers interact with magic. For example, her ability to control water might have an unexpected effect on a magical water - based spell in Hogwarts.
One way they could merge is through a magical portal. Imagine if the demigods from Percy Jackson's world accidentally stumble upon a portal that leads them to Westeros. They might bring their unique powers, like Percy's control over water, and it would disrupt the power balance in Game of Thrones. For example, they could help in battles against the White Walkers, using their god - given abilities. This would change the whole course of the Game of Thrones story.
In many RWBY Space Marine fanfictions, they merge the two universes by having a portal or some sort of interdimensional rift. This allows the Space Marines to end up in the RWBY world. For example, in 'The Astartes of Remnant', a warp - like portal sucks in a group of Space Marines and drops them right into the middle of Vale.
One way they can merge is through character crossovers. For example, a character from Game of Thrones like Jon Snow could be transported into the Warhammer universe. He might find himself in the middle of a battle between different factions in Warhammer, using his skills learned in Westeros to survive. His sense of honor and leadership could also have an impact on the Warhammer characters he encounters.
The two universes blend in various ways. In fanfiction, Percy's powers can be adapted to the Skyrim setting. His ability to control water can be used in Skyrim's many waterways. Also, the mythology of Percy Jackson can be merged with Skyrim's lore. For example, the gods in Percy's world could be compared or even interact with Skyrim's divines.
Well, they often blend the two universes by having the characters meet. For example, Ruby could run into Percy and they start to explore each other's worlds. They might also blend the powers. Maybe Weiss could use her Glyphs while Percy uses his water powers in a combined attack against a common enemy.
In many fanfictions, the two universes merge through magical portals. For example, in some stories, a powerful spell in the Winx Club world accidentally creates a portal to the Pokemon world, allowing the characters to cross over.