The cultural exchange is a really interesting key element. Cassie comes from a very different world than the Naruto characters. Her modern - day, more Western - influenced culture can introduce new concepts to the Naruto world. This could be things like different forms of technology or social norms. And vice versa, the Naruto characters' values like loyalty, hard work, and the importance of the village can have an impact on Cassie. It's these exchanges that add depth to the fanfic and make it more than just a simple crossover of characters fighting together.
One key element is the crossover aspect. How Cassie Cage, a character from Mortal Kombat, fits into the Naruto universe. This includes her adapting to the use of chakra if the author chooses to include that. Another element is the interaction between Cassie and the Naruto characters. Their different personalities and cultures collide, which can create interesting dialogue and relationships. For example, Cassie's bold and straightforward nature might clash or complement Naruto's determined and sometimes naive personality.
In a Cassie Cage Naruto fanfic, the power balance is an important element. Cassie has her own set of skills from Mortal Kombat, like her martial arts and special moves. When she enters the Naruto world, the author has to decide how these skills compare to the ninja abilities. Will she be overpowered, or will she have to learn and grow? Also, the plot often revolves around a common threat that both Cassie and the Naruto characters need to face together. This threat could be something new that combines elements from both universes, like a group of villains using both modern weapons and ninjutsu.