The Reverse Flash could also be a main villain in this crossover. He travels to the Smallville universe to cause trouble. He might target Clark, thinking that by eliminating him early, he can change the future in his favor. This would force Barry and Clark to work together to stop the Reverse Flash's evil plans.
One exciting plot twist could be the discovery of a hidden connection between Smallville's Clark Kent and The Flash's Barry Allen that predates their superhero identities. Maybe they are related in some way through their alien or metahuman genetics. Another could be a villain who has the ability to manipulate time and space, causing chaos in both Smallville and Central City. This would force Clark and Barry to work together in ways they haven't before. A third plot twist might be that a character from Smallville who was thought to be normal actually has latent superpowers that are activated during the crossover, adding an unexpected element to the story.
Clark and Barry would likely start off as cautious allies. Clark, being more experienced in the superhero game in a sense, might initially be a bit of a mentor to Barry. But as they face challenges together, they'd become true friends. Lois Lane would probably be intrigued by Barry's speed and his different approach to reporting. She might even try to get some scoops from him. Meanwhile, Chloe Sullivan could help Cisco Ramon with some of his tech issues, and they'd form a bond over their shared love of all things tech - savvy.
Perhaps in the fanfiction, there's a time - traveling aspect. Barry's time - traveling experiments go wrong and he ends up in Smallville during Clark's high school years. They have to figure out how to get Barry back to his own time while also dealing with a villain who is trying to change the future by targeting Clark in the past. This could involve both of them learning about each other's powers and how to work together effectively.
The ability to reimagine character relationships is also unique. Characters who might not have interacted in their original shows can form new alliances or rivalries in smallville crossover fanfiction. For instance, a character from Smallville could have a completely different relationship with a character from 'Supergirl' in a crossover. This gives fans a chance to see their favorite characters in new lights and explore different emotional arcs.
I really like 'Crossroads of Krypton and the Hunting Life'. In this fanfiction, the writers did an amazing job of bringing in the mythology of Smallville and Supernatural. Dean and Sam Winchester end up in Smallville and get involved with Clark's world. It's full of action and some really cool character moments. It shows how the different powers and skills of the characters from both shows can work together or clash in interesting situations.
I really liked a fanfic called 'Power Convergence'. In this story, the Charmed Ones end up in Smallville and they have to figure out how to get back home. Along the way, they meet Clark and his friends. It's a great read because it shows how the different power dynamics from each show would play out when the two worlds collide.
The clash of different mythologies. Smallville has its Kryptonian and small - town - hero story, while Supernatural has demons, angels, and hunters. When these two collide in a fanfic, it creates a really unique and exciting world. For example, seeing how Clark's superpowers interact with the magic and weapons of the Winchester brothers.
One key element is the character interactions. Seeing characters like Clark Kent and Oliver Queen interact, given their different backgrounds and powers, is really exciting. Another element is the merging of storylines. For example, how the threats in Smallville might be related to those in the Arrowverse.
A common theme is the clash of two different worlds. Smallville is more of a small - town superhero origin story, while Buffy deals with the supernatural in a more urban and 'chosen one' kind of way. So, the fanfics often explore how these two concepts collide.