One possible storyline could be Batman teaching Superboy how to better control his super strength. For example, in a training session, Batman sets up various obstacles that require Superboy to use just the right amount of force to get through. Another could be Batman training Superboy in detective skills. Superboy, with his super senses, has an advantage but needs to learn how to analyze clues like Batman. He might start by learning how to track down a simple thief in Gotham City under Batman's guidance.
A great story idea might be a time - travel plot where Superboy and Batman are sent back in time. They have to work together to stop a villain from changing history. Superboy's powers would be useful for physical combat and Batman's intellect for strategizing. Maybe they end up in Gotham of the past and have to deal with the different versions of Batman's rogues gallery.
One plot idea could be that Batman discovers Baby Superboy and has to protect him from villains who want to use the baby's powers for evil. Maybe Batman has to figure out how to care for a super - powered baby while also keeping him safe.
One interesting storyline could be a reimagining of Batman's first encounter with the Joker in the 1939 fanfiction context. Maybe the Joker starts as a small - time criminal and Batman has to figure out his true motives early on.
One interesting storyline could be Superboy and Supergirl teaming up to face a new and powerful villain that the Justice League has overlooked. They might discover a hidden threat in Smallville that has ties to Krypton's past.
Maybe a story where Superboy discovers a connection between his past and an old case that Batman Beyond is currently investigating. They start to dig deeper and find out that an ancient Kryptonian artifact has been hidden in Gotham and it's the key to a much larger conspiracy involving both their worlds. They have to work together, with Superboy using his powers and Batman Beyond his high - tech gadgets to uncover the truth.
One interesting storyline could be John Constantine and Batman teaming up to fight a supernatural threat that's terrorizing Gotham. Maybe a demon is possessing the city's criminals, and Constantine's magic along with Batman's detective skills are needed to stop it.
One interesting storyline could be about Batman's wife getting involved in his crime - fighting activities secretly. She could use her own set of skills, perhaps in intelligence gathering or martial arts, to assist Batman from the shadows without his knowledge at first. This would add an element of surprise and a new dynamic to the Batman universe.
One interesting storyline could be Batman having to deal with a new villain who has the power to manipulate time while also trying to maintain his normal life as Bruce Wayne. This would add a whole new layer of complexity to his dual identity.
One possible storyline could be Harry leading a group of Hogwarts students in a military - style training to defend the school against a new dark threat. They could learn combat spells in a more regimented way, like soldiers training for battle.
One interesting plot could be Batman teaching Robin advanced combat techniques in a secret, underground training facility. Robin struggles at first but gradually masters the moves.