Well, one possibility is that Cloud's friends would immediately start a rescue mission. They might track Sephiroth's usual hideouts. Since Sephiroth is a powerful foe, they would have to be very strategic.
Maybe Sephiroth has some ulterior motives for kidnapping Cloud. It could be related to a power he thinks Cloud has or some past event between them. Cloud, on the other hand, would probably be trying to find a way to escape while being held captive.
In a fanfiction scenario like this, the story could take many twists. For example, Sephiroth might try to brainwash Cloud to join his side. But Cloud's strong will and his connection to his friends could help him resist. Also, the writer could introduce new characters or elements from the game's lore to add more depth to the situation.
Sephiroth might use Cloud to gain some sort of leverage against their common enemies. Or perhaps he wants to extract some information from Cloud. It's all very mysterious.
Next, Eren could try to escape. Given his strong will, he won't just sit there and accept being kidnapped. He might use his titan powers in a creative way to break free from Levi's clutches.
One possibility is that Gohan's friends and family, especially Goku, would immediately start searching for him. They would use all their powers and resources to track Vegeta's whereabouts. Goku might be enraged and ready to fight Vegeta to get his son back.
Well, Naruto might use his Nine - Tails chakra to break free. He's a tough one. He could also try to outwit Orochimaru with his ninja skills. Maybe he'd pretend to be unconscious and then surprise Orochimaru when he least expects it.
Another scenario could be that Naraku has some ulterior motive for kidnapping Kagome. Maybe he wants to use her spiritual powers for his own evil purposes. He could try to corrupt her or force her to use her powers against Inuyasha and the others. But Kagome would resist with all her might, and her love for Inuyasha and her friends would give her the strength to hold out until they come to her rescue.
In a scenario where Orochimaru kidnaps Hinata, the Hyuga clan would surely get involved. They'd be outraged and use all their resources to find her. Orochimaru might be interested in Hinata's Byakugan for his experiments. He could try to extract its power or study it. But Hinata has been trained in the Gentle Fist style, so she might be able to hold her own against Orochimaru's minions for a while. And who knows, Sasuke might also get involved. He has his own history with Orochimaru and might see this as a chance to confront him again, especially if he realizes that an innocent like Hinata is in danger.
Well, one possibility is that Elena's friends would immediately start a search party. Damon, for instance, would be furious and stop at nothing to find her. He might enlist the help of Stefan and Bonnie. They could use Bonnie's magic to try and track Klaus' whereabouts.
Another aspect could be the emotional turmoil for the other Avengers. They would surely be scrambling to find Tony. Captain America might feel especially guilty, considering their past differences. The team would have to put aside their differences completely to rescue Tony. They might start by gathering intel on Thanos' whereabouts and formulating a plan that involves their unique skills. For example, Black Widow could use her espionage skills to infiltrate Thanos' base, while Thor could provide the brute force needed in a direct confrontation.
Well, one possibility is that Goku's friends would immediately start a search and rescue mission. Vegeta, being his rival but also an ally, would probably be at the forefront. He'd be furious that Broly dared to kidnap Goku. They'd likely track Broly's energy signature to wherever he's taken Goku. Another thing could be that Goku, while kidnapped, tries to reason with Broly. Maybe he discovers that Broly has some deeper issues or motives for the kidnapping that could potentially be resolved through conversation.
One possibility is that her friends, like Percy, would immediately start a rescue mission. They would likely gather all the resources and allies they could find. Maybe they'd consult the Oracle for some clues on where Kronos has taken Annabeth.