One challenge is integrating the different mythologies. 'Supernatural' has its own complex lore about demons, angels, and the like, while 'Dark Angel' has the whole genetic - engineering and post - apocalyptic backstory. Merging these two can be really tricky.
One of the most interesting elements is the exploration of new powers and abilities. When Dark Angel crosses with 'X - Men', the genetic enhancements of Dark Angel characters can be compared and combined with the mutant powers. It's fascinating to see how Max's superhuman strength and agility might interact with, say, Storm's weather - controlling powers. Also, the clash of different story themes is really engaging. In a crossover with 'The Matrix', the idea of a hidden truth about the world in The Matrix can be related to the secrets behind the genetic experiments in Dark Angel. This can lead to some really deep and thought - provoking stories.
Well, a popular Dark Angel crossover fanfiction is the one that crosses it with 'Terminator'. The story could explore how the cyborgs in Terminator interact with the genetically enhanced people in Dark Angel. It often involves high - stakes battles and complex relationships. Another good one is a crossover with 'Firefly'. Here, the characters from both universes find themselves in a shared adventure in space, with Max bringing her unique skills to the table. And there's this really creative one that crosses it with 'Stranger Things', where the Upside Down and the world of Dark Angel collide in an unexpected way.
In some 'dark angel buffy crossover fanfiction', the characters' backstories are explored in relation to each other. Maybe Buffy discovers that there are some similarities between her calling as a slayer and Max's situation as a genetically enhanced being. They could bond over their sense of being different from the normal humans around them and their responsibility to protect those who can't protect themselves. This type of fanfiction often delves deep into the emotional and psychological aspects of the characters, making it a more complex and interesting read.
Fanfiction.net is also a good place to search. There are many different categories and tags, so you can specifically look for crossovers between 'Dark Angel' and 'Buffy'. Just be prepared to sift through a lot of stories to find the ones that interest you the most.
One idea could be that the vampires in Buffy's world somehow cross over to the Dark Angel universe and the transgenic characters have to deal with them. They might initially mistake vampires for some new kind of transgenic experiment gone wrong. Another idea is that Buffy herself travels to the Dark Angel world and teams up with Max to fight against a common enemy that is threatening both of their worlds, like a powerful demon that has found a way to use transgenic technology for evil purposes.
One idea could be that a case in NCIS leads them to discover a secret project related to the genetic experiments in Dark Angel. Maybe they find a link between a murdered Navy officer and a group trying to recreate the transgenic experiments. So, the NCIS team has to work with Max from Dark Angel, who has her own knowledge and skills in this area.
One great piece of 'supernatural dark angel crossover fanfiction' is 'The Angelic Hunt'. In this story, the characters from both shows team up to fight a common evil. It has an interesting plot that combines the mystery elements of 'Supernatural' with the post - apocalyptic and genetic - engineering aspects of 'Dark Angel'.
In my opinion, Faith from Buffy and Alec from Dark Angel would be great to focus on. Faith has her own troubled past and her unique slayer abilities. Alec, on the other hand, is a transgenic with a bit of a roguish charm. The two of them could have a really interesting dynamic. Maybe they start off as rivals, not trusting each other, but as they face a common enemy, they start to understand and respect each other. And of course, Buffy and Max are also must - haves. They are the main characters of their respective shows and their leadership skills and different outlooks on life would make for a great story.
Another theme is the idea of family. In Supernatural, Sam and Dean have a strong brotherly bond, and in Dark Angel, Max has her own 'family' among the transgenic group. In crossover fanfic, these family concepts often collide and merge. For example, the transgenic might be seen as a new kind of 'family' by the Winchesters or vice versa. It's about how different forms of family support and protect each other in the face of danger.