This might just be a one-shot for now. All characters and concepts belon to DC and Terry Pratchett.
Idea came to me a month ago when I re-read Thud. Hopefully I didn't mess up any of Discworld or Batman's canon in my attempt to merge them. I was a bit lazy on the research, I admit.
The Bat-Man of Ankh-Morpork
A wagon rolled up to the gate.
"Alright, state your name and what you've got in the wagon, stranger."
"Lord Wayne has returned. In the wagon, he rests. I would advise you not to wake him, the master can be somewhat cranky when roused."
"That's as may be, sir, but Mister Vimes would have my head if we gave some bugger half a chance to smuggle in something dangerous in the city, so soon after the Roundworld Incursion dumped loads of gonnes in the Shades a month ago. Open the back, please."
"Very well."
The wagon's door was opened.
Within, a young man, dressed in clearly well worn traveling gear was slumped asleep on the floor, murmuring about a cave and shadows.
"We have had a rather trying time in Überwald, when we left after some madman killed his parents in the Shades, damn silly fools they were. The Lord has not rested easily until now, returning back home where he belongs. He is a Wayne. You look too young to remember, but his parents were one of the few aristocratic families who assisted the rebels in the Glorious Revolution. He has spent twenty years waiting for the circumstances to change, for Morpork to be suitable for his intentions of charitable works to not be blocked by another Snapcase."
"Well, I can't guarantee that, but yeah, it's a bit better nowadays. You're free to pass. But, please, do yourself a favour, guv, and get yourself registered with the Guild of Servants, Aides, and Hired Help, or they'll come down on you like a ton of featherdusters and polish."
"I... See some things have changed. I am sure I will learn."
Stately Wayne manor had been badly damaged. One of Ronny "Stupid" Johnson's finest works, it was intended as a water purification facility for the Ankh, to make it more like water, and as such, due to the Johnson method, ended up as a chaotic mess of pipe work that had a sizeable mansion attached to it, and the cavern below had seemingly been uncovered, then very quickly hidden and abandoned by dwarves upon the slow creation of the Under City of Ankh-Morpork. Something kept the dwarves from wanting to investigate the cavern.
Bruce Wayne entered this cave now, ignoring the squelching noise of the moist bat guano beneath his feet.
"I know you can see me, Watcher. You lurk in the shadows, striking only when needed, utilisng fear and confusion to aide you. This city needs you. I need you."
There was an opening there. Bruce had trained with Bardic Monks of Llamedos, who were trained in the art of ensuring events fitted a particular story of their own making, with the intent to change other stories to make them fit into the overarching plot of their own design. Good storytellers were often given a chair as prize. The talented ones manipulated the story of reality so they got a throne, and all that came with it.
The best seemingly lived ordinary lives as musicians and storytellers, but somehow gained their every desire in the process.
Never underestimate the bard in a world that is based on stories.
There was a flicker of darkness, darker than the gloom all around.
"You once had no name, but I felt your call, far from here."
A faint outline of a man holding a lantern, in watchman's gear, black on the black surroundings was faintly visible as Wayne blinked.
"You are a newborn deity of sorts. Forged from dwarven lore..."
The sound of footsteps, in time with the jostling movements of bats above.
"I serve you... Guarding Darkness."
The faint symbol of a watchman's lantern appeared in the darkness, for the briefest moment, shining the brightest light he had even seen, or so Bruce claimed later to Alfred.
Startled,a flock of bats came from the shadows, and buffeted Bruce, as they had in his youth before he fled with his butler to the frozen wastes of Uberwald, but this time, he stood firm.
And then they knocked him over.
That did not fit the plan for how the story would make sense. Falling over meant that it was less dramatic. That Ruined The Story.
But it was of no matter. The Guarding Darkness had acknowledged his existence, and given him a warning too, by knocking him over. It was not beholden to the whims of a mere human, and it was not to bow before him, although it would assist so long as it suited it. Deities need followers, and the Guarding Darkness felt stronger with the human's worship.
It was time to return to society. It was time to secure the materials to become the Knight this city needed, a Watchman unbound by their rules, but adhering to his own set of rules all the same, complimenting each other.
Discworld is rather like a sponge, made of narrativium. It absorbs and regurgitates ideas, in and out of itself, concepts from others universes.
It had just absorbed Batman. With the Green Lantern logo somehow getting in the leak from the DC multiverse.
The suit was complicated.
He wasn't actually sure how to fit so much in the belt. He considered compressing it all, and having each compartment springloaded, but it ended up being too risky. If he jumped with the special harness he had on, random bits of metal would pop out. Also, sometimes it would get stuck, and upon being forced open, a curly Thing he did not remember putting in there be the cause. It was enough to nearly make him a devout Anoinian, except that he knew that his ambiguity over his religious worshipped gave him ample capability to effectively summon a lightning storm.
A Bard-Monk (Barte-Mon? Ah, Bat-Man, So be it, Darkness! I will be the Bat-Man!) used whatever dramatic effect he had available, because the sort of world they lived in occasionally would attempt to steal the drama for comedic purposes. Understanding the mechanics of the world was important.
Knowing how to fight was equally so. But knowing how to fight in his chosen outfit would be more useful.
The problem was that he could not wear plate or chain. Chain was cheaper, and could bunch up against piercing strikes, but wasn't entirely suitable for stealthy use. Same problem with plate, but with bonus weight. Thick leather could be used, but it would be too squeaky, at least if he got it new. He needed something protective, non-magical, and thick enough to take a knife, but he can move quickly in.
He considered getting some rubber from the Sonky factory, and dying it in black, but somewhere, deep in his mind, he felt a sudden sense of foreboding with that idea, as he suspected the Times would run an article calling him something embarrassing.
Stealthy. Agile. Strong. Protective.
He sketched out a simple design on a piece of paper, but then tossed it aside. The eyebrows were silly.
Bruce Wayne could not work it out alone. He decided, ultimately to request help, off the Artificer's Guild, and perhaps the Seamstress' Guild.