Another theme is the journey of self - discovery. Characters from both universes often find themselves in a new and unfamiliar world (either Hogwarts or Narnia). This forces them to learn more about themselves, their abilities, and their values. For instance, a Harry Potter character in Narnia might realize they have a different kind of courage than they thought. In a more detailed sense, in some fanfics, Hermione might find that her knowledge of spells doesn't always help in Narnia and she has to rely on her wits and intuition more, which is a new aspect of her self - discovery.
One great Narnia x Harry Potter fanfic is 'The Wizard's Quest in Narnia'. It combines the magical elements of both universes really well. The characters from Harry Potter find themselves in Narnia and have to adapt to its rules and face new challenges there.
A common theme is the exploration of different magical systems. In these fanfics, the magic of Narnia and that of the Harry Potter world often interact. For example, the use of spells in Harry Potter and the magic of the talking animals in Narnia might be combined.
There are fanfics where the magical creatures from both universes interact. For example, the centaurs in Narnia might meet the centaurs from the Forbidden Forest in Harry Potter. This can lead to a whole new set of adventures and cultural exchanges between the two groups of magical beings.
A really cool concept in this type of fanfiction is when the magic items from both universes interact. Like, what if the Philosopher's Stone was brought to Narnia? How would it affect the balance of magic in Narnia? And how would the Narnians react to such a powerful and mysterious object?
Another one is 'Potter and the Chronicles of Narnia'. In this fanfic, Harry Potter himself discovers a portal to Narnia. He then has to use his knowledge of magic from his own world to help the Narnia characters in their battles. It's a long and detailed fanfic that delves deep into the lore of both series and how they could co - exist.
Perhaps the Philosopher's Stone somehow gets transported to Narnia. Harry and his friends follow it there. In Narnia, they find that the stone has a different kind of magic which is intertwined with the magic of Narnia. They have to learn about Narnia's magic system while also protecting the stone from the villains in both worlds.
Hermione Granger is also very popular. Her intelligence and knowledge of magic would be valuable in Narnia. She could study the magic in Narnia and perhaps find ways to combine it with what she already knows from Hogwarts.
Often, the magic systems are blended so that the magical objects from both universes play a role. The Narnian rings might have a connection to the Horcruxes in Harry Potter. Maybe they are both created using similar dark magic, or they can be used to counteract each other's powers. This creates a lot of potential for exciting plot twists and character development in the fanfic.
Character crossovers are also a big part. Imagine Harry Potter interacting with the Pevensie children. It creates new and unexpected relationships. For example, Ron might befriend Mr. Tumnus, and their different personalities would lead to some really funny and heartwarming moments. Also, the fanfic often explores different power dynamics. Since the magic in Narnia and Harry Potter is different in nature, seeing how characters from one world adapt to the other's magic is very interesting.