It might also combine them by setting the Tetris game in the Hogwarts castle. So, instead of a plain background, you have the Great Hall or the Gryffindor common room as the backdrop for the game. The sounds of the game could be replaced with magical noises like spells being cast or the flapping of a hippogriff's wings.
It can combine the two by having the characters cross over. For instance, Harry could be invited to MI6 to share his knowledge of dark magic as they face some sort of dark magical threat in the Muggle world.
By having the characters cross over. For example, the Hogwarts students could attend a WWE event and get inspired to become wrestlers. Or WWE superstars could visit Hogwarts and learn about magic.
In a Transformers Beast Wars and Harry Potter fanfiction, you could have the Transformer beasts being hunted by the Ministry of Magic because they are seen as dangerous magical creatures. Or perhaps some of the Hogwarts professors are interested in the advanced technology of the Transformers. For instance, Professor McGonagall might study the shape - shifting abilities of the Beast Wars characters and try to find similarities with Animagi. Also, the battles between the good and bad sides in both universes could be intertwined. The Autobots could team up with the Order of the Phoenix to fight against the combined forces of the Decepticons and Death Eaters.
In such a fanfic, the writer might draw parallels between Dumbledore's wisdom and Yoda's Force insights. Maybe they create a situation where their powers and teachings complement each other in unexpected ways. There could also be a shared quest or mission that brings them together.
They can combine in terms of magic systems. In some fanfictions, the powerful and often incomprehensible magic in the Cthulhu universe might blend with the more structured magic of Harry Potter. For example, a spell in Harry Potter might be corrupted by Cthulhu's influence and become a more dangerous and unpredictable force.
The 'Harry Potter Fire Lord' fanfiction can combine the two universes by creating a portal or a magical accident that transports characters from one world to the other. For instance, a spell gone wrong in Hogwarts could send a character to the world of the Fire Lord.
Often, it combines them through crossovers. For example, a portal could open between the Naruto universe and Shinji's world, allowing characters to travel between them.
Yes, it is possible. In fanfiction, the boundaries between different universes can be blurred. For example, one could create a story where Harry Potter, as the Master of Death, somehow gets transported to the realm of Loki. Maybe Loki has a plan that involves Harry's power over death, or perhaps Harry is on a quest that leads him to cross paths with Loki. The magic systems in both universes could be intertwined in interesting ways. For instance, the magic in Harry Potter is more about spells and potions, while Loki has his own Asgardian magic. A good fanfiction could find a way to make these two types of magic interact, like Harry using his Patronus charm against one of Loki's illusions.
It could use a portal or some sort of magic - tech device. For example, a magical experiment in the Harry Potter world goes wrong and creates a portal to the Marvel universe where Black Widow is. Or maybe a Stark Industries experiment accidentally taps into the magic of the Harry Potter world. This would be a simple and straightforward way to bring the two together.
You could start by creating a magical portal that connects the two worlds. Then, have characters from each story interact and face challenges together. Maybe a dragon helps Harry in a Quidditch match!