Maybe James Bond and a character from a post - apocalyptic fandom. Bond is used to high - stakes espionage in London, and the post - apocalyptic character could bring a different perspective. They might meet when Bond discovers a threat that is related to the post - apocalyptic world's problems, and they have to work together to stop it. The contrast between Bond's suave sophistication and the post - apocalyptic character's survival skills would be exciting.
One possible plot could be that characters from two different fandoms accidentally meet during a big event in London. For example, a wizard from a fantasy fandom and a detective from a crime-solving fandom cross paths while investigating a mysterious occurrence in the city. They initially distrust each other but as they realize they are both after the same goal, they team up.
If it's a fantasy - based fanfic, there could be magical creatures. Maybe a wizard from another realm meets a human in London who has a special power they didn't know about. Their meeting in London could be the start of an epic adventure to save both their worlds.
It could be the combination of different universes and characters. When well-written, it creates unique storylines and unexpected interactions.
Perhaps it's a business - related fanfic. People from different companies come to London for a meeting. There could be power plays, secret alliances being formed, and unexpected revelations during this London meeting. For example, a young entrepreneur might meet a big - shot investor at the meeting and try to convince them to invest in their startup.
Obviously Naruto would be one of the main characters. And from 'The 100', Clarke would likely be a main character as well since she is a central figure in her own show.
If it's a crossover with a magical world, then perhaps a new character could be introduced as the main character. A young wizard who befriends Manny, Sid, and Diego. This wizard could be the one to bring the Ice Age world and the magical world together. But still, Manny, Sid, and Diego would play important supporting roles as the main characters navigate through the crossover story.
Ayano could also be a main character. Her connection to Kazuma and her own abilities within the 'kaze no stigma' universe could bring a different dynamic. In a crossover, she might be the one to discover the secrets of the new world they enter or be the one who has to make difficult decisions about how to interact with the new characters.
Loki and Zuko could be main characters in such a fanfic. Zuko has his own journey of redemption and Loki has his own complex past. They could bond over their struggles with identity and family. Zuko's firebending skills would also be an interesting contrast to Loki's magic. They could either become enemies or form an unexpected friendship as they navigate the challenges in a world that combines the elements of Asgard and the Avatar universe.
Definitely Doomguy as one of the main characters. He is the iconic figure of the Doom series and his presence is essential. Another could be Lara Croft from the Tomb Raider series. Her skills in exploration and combat could complement Doomguy's abilities. They could be on a quest to stop an ancient evil that has ties to both their worlds, like a demonic force that is also seeking some powerful artifacts that Lara has been studying.
Twilight Sparkle could be a main character. Since she is very intelligent and curious, she might be the one who gets drawn into the Creepypasta - related events. Her knowledge of magic could also play a crucial role in either solving the problems caused by the crossover or in getting trapped in the first place.