Another theme is adaptation. Kiritsugu has to adapt to new environments, whether it's a world full of advanced technology or a place with different magic systems. In a crossover with a sci - fi world, he has to figure out how to use his skills in a world where guns might be obsolete and new forms of combat exist. Also, exploration of his past is common. His backstory as an assassin is often delved into deeper when he is in a new and unfamiliar world.
One common theme is the clash of different moral codes. Kiritsugu has his own set of beliefs, and when he is crossed over into other worlds, like a world of superheroes or a magical realm, his way of thinking often clashes with the local characters. For example, in a crossover with a world of knights, his willingness to use underhanded tactics for the greater good might be at odds with the knights' chivalry.
The theme of power levels is also present. When Kiritsugu is in a world with super - powered beings, like in a crossover with a superhero universe, his relatively 'normal' human skills are contrasted with their extraordinary abilities. This can lead to interesting scenarios where he has to use his wits more than ever. Additionally, the theme of redemption or self - discovery often pops up. In a new world, he may have the chance to re - evaluate his life choices and seek a form of redemption or a new purpose.
One great kiritsugu emiya crossover fanfiction is 'Kiritsugu in the World of Harry Potter'. It imagines Kiritsugu being summoned to the wizarding world. His skills and unique moral code create really interesting interactions with the characters there. Another one could be 'Kiritsugu and the Avengers Crossover'. Here, he teams up with the Avengers and his strategic mind helps them in battles in a very different way compared to their usual approach.
One common theme is power and its consequences. Since Shirou has godlike powers in these fanfictions, it often explores how such great power affects him, whether it corrupts him or makes him a better person.
One common theme is redemption. Since Archer has a complex past filled with regrets, many fanfictions focus on him trying to make up for his past mistakes. Another theme is power exploration. Writers often explore how Archer can further develop his powers or use them in new ways.
One common theme is redemption. Given his complex past in the Fate series, many fanfictions focus on Emiya Archer trying to make amends for his actions. Another theme is self - discovery. He often has to figure out more about his powers and his place in the world.
In these crossovers, a frequent theme is the struggle between good and evil. The Teen Wolf world has its villains like the Nogitsune, and Fate/stay night has its own antagonists. When the two worlds collide in fanfic, the combined forces of good (including Emiya and the Teen Wolf heroes) have to face new and often more powerful threats. Additionally, self - discovery is a theme. The characters from both universes might find new aspects of themselves when exposed to the other world's concepts and challenges. For example, an Emiya - like character might learn something about loyalty from the Teen Wolf pack, while a Teen Wolf character could gain new perspectives on power from Emiya's magic.
One common theme is redemption. Given Kiritsugu's complex past, many fanfics explore his journey towards redeeming himself in the context of the Beast Lair.
One common theme could be the exploration of their different natures. Ereshkigal is from a different realm and has her own set of powers and characteristics, while Emiya has his own backstory and abilities. Their interactions in terms of how they deal with these differences can be a theme.
Family or surrogate family is also a theme. It could be about how the characters around him form a sort of family unit and how that affects his growth. Maybe he is taken in by a group of mages who raise him with different values compared to his original upbringing in the official story, and this changes his outlook on life and heroism in the fanfiction.
The theme of self - acceptance is also prevalent. Female Emiya Shirou may face different challenges compared to the male version, and coming to terms with who she is and her place in the world is often a central part of the story. There are also fanfictions that explore the theme of sacrifice, just like in the original Fate story. She might have to make difficult choices for the greater good, and her gender can add a new dimension to these decisions, such as how society might view a female making such sacrifices differently.
One common theme is power and its consequences. Shirou often gains new powers related to the dragon, and the fanfictions explore how he copes with that. Another theme is loyalty, whether it's Shirou's loyalty to his new dragon ally or vice versa.