One idea could be that Percy Jackson is somehow transported to the world where Ghost Rider exists. He has to team up with Ghost Rider to fight a common enemy that is threatening both their realms, like a powerful demon that can manipulate water (to challenge Percy) and fire (to challenge Ghost Rider).
Maybe Ghost Rider ends up in the Percy Jackson universe. The demigods are initially scared of him but then realize he could be an ally. They work together to stop an ancient evil that has the power to destroy Olympus. Ghost Rider's hellfire could be used in unique ways against the monsters in the Percy Jackson world.
One unique plot idea could be that Percy discovers he has a special connection to the dragons because of his demigod powers. Maybe he can communicate with them on a deeper level than others. Another idea is that the dragons are the key to solving a new threat to the demigod world, like a powerful ancient evil that only the combined strength of the demigods and the dragons can defeat.
There could be. Fanfiction writers are very creative and love to combine different well - known characters. Since Percy Jackson has his own set of powers and the Ghost Rider has his very distinct abilities, a fanfiction where Percy is the Ghost Rider would be a really cool concept. It might explore how Percy would handle the power of the Ghost Rider, how it would interact with his demigod nature, and what new adventures he could have. So, it's very likely that someone has written such a fanfiction.
One plot idea could be Percy having to team up with Hera to rescue a group of demigods who have been captured by an ancient monster. Hera, despite her usual aloofness, realizes she needs Percy's unique skills.
In a 'Percy Jackson is the Ghost Rider' fanfiction, it would start with Percy getting the Ghost Rider's powers in some unexpected way. Maybe he stumbles upon an ancient artifact that binds the two powers together. With the Ghost Rider's powers, he would have enhanced strength, the ability to see the sins of others, and of course, the iconic flaming skull. Percy would use these powers to protect not only the demigod world but also the normal human world from the threats that the Ghost Rider is known to combat. His relationship with his friends would change as they try to understand his new powers. Some might be scared, while others would be eager to help him master them. And Percy would have to figure out how to balance his two identities, the demigod son of Poseidon and the Ghost Rider, all while facing new and dangerous enemies that are attracted to his unique combination of powers.
One idea could be that Naruto somehow inherits the Ghost Rider bloodline. He could then use the powers of the Ghost Rider in his battles in the Naruto world. For example, his Rasengan might be infused with the hellfire of the Ghost Rider, making it an even more powerful attack.
A possible plot is that the Ghost Rider's hellfire has an unexpected effect on the vampires in Twilight. Since vampires are undead, the hellfire might either have no effect, or it could be the one thing that can truly destroy them. This could lead to a race between the vampires and the werewolves to either use or stop the Ghost Rider. Also, the Ghost Rider could form an alliance with the werewolves as they are more in tune with the natural order which the Ghost Rider also represents in a way.
A crossover with Kamen Rider Zi - O could also be really cool. Zi - O travels through time, so he could accidentally disrupt the timeline in a way that affects Ghost's world. Ghost might have to team up with Zi - O to fix the timeline while also dealing with the enemies that are taking advantage of the time - chaos. They could encounter different versions of themselves from alternate timelines and have to figure out how to make things right.
A plot could involve a magical accident that fuses Naruto and Ghost Rider's essences. This new being has a strange allure and power. In the Naruto universe, female characters start to gather around this new entity. There could be a lot of drama as the harem members come from different ninja clans and have different motives. Some might be in it for the power, some for true love, and they all have to deal with the challenges that come with this new and powerful being in their midst.
Another plot could involve the two universes being on a collision course because of some interdimensional rift. Ghost Rider and the main characters of Black Lagoon must work together to close the rift while also dealing with the threats that come from both worlds merging. There could be a lot of action and character development as they learn to trust and rely on each other in this strange situation.
Maybe the Ghost Rider's powers are somehow connected to an ancient magic in Equestria. He could be on a quest to find out the origin of his powers and in the process, he befriends Rainbow Dash. Rainbow Dash is intrigued by his ability to fly on his flaming motorcycle and they start to explore different parts of Equestria together, all while uncovering secrets about his powers.