You could write a fanfiction where the Nightwing OC is from a different dimension. This OC could bring unique powers or a different perspective on heroism to the story. For example, their dimension might have different rules about using powers in public, which could lead to interesting conflicts and discussions with Nightwing.
Some fanfictions focus on the emotional aspect of a Nightwing x OC relationship. They might delve into how the OC helps Nightwing deal with his past traumas, like the loss of his parents. The story could show how their love and support for each other grows over time as they face various villains and challenges together in Gotham.
To develop a believable Nightwing OC, focus on their relationships. If they have a mentor, how did that relationship start and how does it influence them? Their relationships with villains can also be important. Maybe they have a personal vendetta against a particular bad guy. And don't forget about their flaws. No one is perfect, so giving your OC flaws like a short temper or over - confidence makes them more relatable.
First, you need to develop your OC well. Give them a unique personality, backstory, and set of skills or powers. For example, if your OC is a detective, explain how they got into that line of work. Then, focus on the relationship with Nightwing. Build it gradually, starting from their first encounter.
He might try to reason with kaldur. If Nightwing can make kaldur see that what he's doing is wrong or that there are better ways to achieve his goals, kaldur could let him go. Nightwing is known for his charisma and intelligence in such situations.
He might try to engage Slade in conversation. Nightwing is smart and could be looking for a way to psychologically get an edge over Slade. He could be probing for Slade's motives, hoping to find a way to turn the situation around. He might also be stalling for time, waiting for the right moment to make his move.
Batman is the most likely. He has a strong bond with Nightwing and would do anything to save him. His skills in combat and detective work would be crucial in finding and freeing Nightwing.
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.
Batman could be a main character. Since Nightwing was trained by Batman, in a baby Nightwing fanfiction, Batman could be the one taking care of him, teaching him basic skills, and protecting him from the threats of Gotham.
Captain America could be a strong ally for Nightwing. Captain America is a great leader and has a strong sense of justice. Nightwing, coming from Gotham, also has a deep - rooted sense of right and wrong. They could lead the Avengers together in a battle, with Captain America providing the strategic leadership and Nightwing using his agility and combat skills to execute the plans on the ground.