Ryuki himself is a popular choice. His complex backstory and his quest for justice in his own universe make him an interesting character to explore in a crossover. He has a strong sense of right and wrong and his fighting style is cool.
For the Dragon Knight side, Kit Taylor could be a popular character. He is the main protagonist in that series. His journey from an ordinary guy to a powerful Dragon Knight is full of potential for character development in a fanfiction. He could bring a different perspective to the events compared to the Kamen Rider Ryuki characters.
Odin is also a great character to focus on. His mysterious nature and his power level make him stand out. In a fanfiction, he could be a key player in the events that unfold between the two universes, perhaps having his own hidden agenda.
Ryuki is often very popular. He's the main character in the original series, so he's a natural focus in fanfiction. His journey and his growth as a rider make him an interesting character to write about.
Another plot could involve a misunderstanding between the Kamen Rider Ryuki and Dragon Knight characters that leads to an initial battle between them. But as they fight, they start to realize they have more in common than they thought and end up joining forces. For example, they could discover that a shadowy organization is manipulating events to keep them at odds.
Well, from the Kamen Rider universe itself, characters from Kamen Rider Blade could be great for a crossover. Their different powers and personalities would create interesting interactions with the Ryuki characters. Another suitable character could be Kiva. His vampire - like nature and unique fighting style would add a new flavor to the Ryuki crossover.
One idea could be exploring an alternate universe where the riders form different alliances. For example, some of the more antagonistic riders team up against a common threat that is far more powerful than any single rider. This could lead to interesting character development as they have to put aside their differences.
Some of the more popular Kamen Rider characters might be Kamen Rider Decade, as his ability to travel through different Rider worlds gives a lot of scope for crossovers. In terms of magical girls, Sailor Moon is often a popular choice as she is one of the most well - known magical girl characters globally. Her powers and strong sense of justice can create interesting dynamics with the Kamen Rider characters.
Often, Iron Man from the Avengers and Kamen Rider Decade are popular. Iron Man's high - tech gadgets and intelligence make for interesting interactions with the unique powers of Kamen Rider Decade. They can both be seen as leaders in their respective groups, so seeing them work together or clash in fanfiction can be really engaging.
Another popular character could be Blake Belladonna. Her stealthy nature and her ability to use her shadow clones could interact well with the kamen rider powers. In fanfiction, she might team up with a kamen rider to take on enemies that are difficult to defeat using her normal RWBY abilities alone. For example, a kamen rider's ability to detect hidden threats could complement Blake's stealth skills.
Kamen Rider Decade is often a popular choice. His ability to transform into other Riders makes him a natural for crossovers. He can bring in elements from different series and connect various storylines together.
Natsumi Hikari is a popular character in Kamen Rider Decade fanfiction. She provides a sort of 'normal' perspective in the otherwise extraordinary world of Riders. Writers might explore her growth from being a somewhat reluctant companion to Decade to becoming a more confident and important part of his adventures. Her relationships with other characters, especially Decade, are often a focus in fanfiction.
Naruto is likely to be very popular as he is the main character from his own series. His energetic and determined personality can bring a lot to crossovers. Hibiki too, as the titular Kamen Rider, has his own fan following. His unique design and combat style make him stand out.