In the fanfiction, Nightwing could be used by the Joker as bait to lure Batman into a trap. The Joker might have some elaborate and sadistic plan in store for both of them. Nightwing, being the strong - willed character he is, will likely try to resist the Joker's psychological games and attempts to break him while waiting for rescue.
Another scenario could be that the Joker tries to turn Nightwing into one of his minions. He might use some kind of mind - control device or just his demented psychological manipulation. But Nightwing has his own moral code and loyalty, so he'll fight tooth and nail against this transformation, all while trying to find a way to escape the clutches of the Joker.
It's also possible that Nightwing and Slade end up having a long conversation during the captivity. Slade might try to convince Nightwing to join his side, perhaps by appealing to some sense of justice that he thinks Nightwing is missing. Nightwing, of course, would resist, but this could lead to some interesting character development for both of them as they debate their different ideologies.
One possibility is that Robin, being kidnapped, will have to rely on his own wits and skills he has learned from Batman. He might try to outsmart the Joker by finding weak points in the place where he is held captive. For example, if it's an old warehouse, he could look for ways to escape through the ventilation system or by using some tools he might find around. And the Joker, being the unpredictable villain, could be constantly taunting Robin, trying to break his spirit before Batman arrives.
One possibility is that Red Hood has some sort of vendetta against Nightwing. Maybe he blames Nightwing for something that happened in the past, like a mission gone wrong that affected someone close to Red Hood. So he kidnaps Nightwing to get revenge or to make him pay in some way.
Nightwing would initially be defiant. He's a highly trained fighter and detective in his own right. So, he won't cower in front of the Joker. He'll probably try to size up the situation, looking for any weaknesses in his captivity and the Joker's plan.
In a 'Wonder Woman kidnapped by Joker' fanfiction, the story could start with the Joker devising an elaborate plan. He could use his henchmen to distract Wonder Woman while he sets up a device to incapacitate her. Once kidnapped, Wonder Woman would be in a tough situation. The Joker might keep her in a strange and dangerous location. She would have to use her strength, both physical and mental, to break free. There could be moments where the Joker thinks he has the upper hand, but Wonder Woman's determination and heroism would shine through as she tries to outwit him and get back to saving the world.
Well, in a fanfiction like this, Naruto might be in for a tough time. Pan could be from some other universe and have her own motives. Maybe she wants to use Naruto's powers for her own gain. It could lead to a really strange adventure where Naruto has to figure out how to escape and get back to his own world.
First of all, the setting of the kidnapping is crucial. Is it in a desolate desert or a crowded city? If it's in a city, there might be more chances for Tim to signal for help. In this fanfiction, the outlaws could also have their own backstories that led them to kidnap Tim. For example, they might think Tim is involved in something that affected their group negatively. As the story progresses, Tim could discover some secrets about the outlaws that could either help him escape or make his situation worse.
Perhaps Itachi sees Naruto as a key to unlocking some hidden power or knowledge. He could be planning to train Naruto in some way, away from the influence of the village. This would be a strange turn of events considering their previous interactions.
Another scenario could be that Loki forms an unexpected alliance while in captivity. He could meet some other captives who have a grudge against Thanos. Together, they could plot against Thanos from the inside. Loki's silver tongue might be able to convince these captives to trust him and follow his lead. They could create a distraction or a mutiny within Thanos' forces, which would give Loki an opportunity to either escape or turn the tables on Thanos.
Well, she could be held in a secret location. Maybe Lopez has some ulterior motives, like getting information from Felicity. He might try to use her skills for his own gain.