One possible plot for this fanfiction could be that Bane kidnaps Robin as part of a revenge plot against Batman. Robin is trapped in a dangerous situation, and he has to rely on his training and his mental strength to survive. Bane might taunt Batman with messages about Robin's kidnapping. As Batman races to save Robin, Robin also tries to find a way to free himself and help Batman in the process. The story could explore Robin's growth as a character while facing this difficult situation and the complex relationship between Batman, Robin, and Bane.
It could be Nightwing. He was once Robin himself and has a special connection to the current Robin. Nightwing might hear about the kidnapping and step in to save Robin, using his own unique fighting style and experience.
One possible plot twist could be that Robin has been secretly trained in a new combat technique that he uses to outwit Deathstroke when Deathstroke least expects it. Maybe he pretends to be more injured or helpless than he really is, and then strikes back at a crucial moment.
Well, one possible plot development could be that the kidnappers demand a ransom from Batman. Batman then has to race against time to find Robin without alerting the media or causing panic in Gotham. Another development might be that Robin manages to leave some hidden clues for Batman to find while being held captive. Maybe he uses his martial arts skills to briefly overpower one of the kidnappers and mark a symbol on the wall that only Batman would understand.
Robin would probably be both scared and angry. He's a brave kid, but facing the Joker alone is no small feat. He might initially try to fight back if he has the chance.
The other Teen Titans could also play a big role in the rescue. Starfire could use her powers to fly in and distract Slade while Cyborg and Beast Boy create a diversion. Raven could use her magic to break any spells or traps that Slade has set for Robin. They would all work together as a team to get Robin back safely.
One idea could be that Poison Ivy kidnaps Robin to use him as a bargaining chip against Batman. Maybe she wants Batman to stop interfering in her environmental plans. So she holds Robin in her lair, which is filled with all kinds of dangerous plants.
In the world of fanfiction, there are often hidden gems. For 'Robin kidnapped' fanfictions, you might find good writers by looking at the reviews and ratings of stories with this plot. Writers who get a lot of positive feedback for their take on this theme are likely to be good. They may be skilled at character development, making the story of Robin's kidnapping and possible rescue really engaging.
Robin could use his intelligence to analyze Deathstroke's lair and find a weakness in its security system. He might notice a pattern in the guards' patrols or a flaw in the locking mechanisms. Then, he could use his acrobatic skills to create a distraction and slip away unnoticed.
Robin would probably stay calm and observant. He's been trained well, so he'd immediately start looking for any weaknesses in his captivity situation. He might try to pick the locks on his restraints if he's bound, or find a way to communicate with his team secretly if there's a chance.
One possible plot twist could be that Red X has a hidden agenda that's not actually malicious towards Robin. Maybe he's trying to protect Robin from a greater threat that the Teen Titans are unaware of. For example, there could be a new super - villain in the city who is targeting the Titans, and Red X believes that by taking Robin, he can keep him safe until the danger passes.