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It began the way most things did in Wayne Manor: with Damian bursting into a room like he owned the place. He shoved open the double doors to the sitting room, his feet hitting the floorboards with the same precision as a soldier marching into battle. Heads turned.
Jason was sprawled on the couch with a book, Steph and Cass were mid–card game on the rug, and Tim and Bruce were playing chess, both staring the other down intensely. Dick had claimed the armchair, legs tucked beneath him like a cat, and was chatting with Barbara, who was next to him. Alfred drifted in with a tray of tea, calm as ever, while the fire threw a soft glow across the room.
Damian stopped dead centre with a blanket cape flaring out behind him and crossed his arms as everyone stared at him, except for Tim and Bruce, who were locked in a silent battle of wills over the chessboard.
He drew himself up to his full height, as if he was about to impart life-altering information. His voice rang with the seriousness of a briefing in the Cave. “I have been invited to a civilian ritual. One involving the collection of sugar-based confections while in disguise, followed by an overnight siege.”
Jason’s head tilted, dropping his book into his lap. “Translation, please.”
Tim didn’t even glance up from the chessboard. “Trick-or-treating. Then a sleepover.”
“Yes.” Damian’s tone was clipped. “My first such event. Failure is not an option. I require a disguise.”
For a moment, there was silence. Then Dick lit up, practically bouncing out of his chair. “Oh my god, your first Halloween? You’d look adorable as a pumpkin!”
Damian’s glare could’ve cut glass. “I am not a toddler.”
For the last few years, Damian had flat-out refused to participate in what he called “An American capitalist agenda disguised as mass sugar consumption.” No amount of cajoling, bribery, or Bat-level psychological warfare could sway him.
The family had tried everything: Dick’s pep talks about childhood joy, Jason’s threats to eat all the candy himself, and a live performance with various costumes by Tim, Steph, and Duke. None of it worked.
The only holiday they’d managed to make a dent in was Christmas, but that was less about festive cheer and more about Damian’s insistence that Santa Claus was clearly a home intruder, and he must be brought to justice. Every Christmas Eve, he prowled the Manor like a miniature security detail, armed with grappling hooks and a grim determination to catch the old man red-handed.
What had started as a headache had, inevitably, become tradition. “The Santa Protocol” was now a fully-fledged event: the rest of the family working together with near-military coordination to deliver presents under Damian’s nose.
It was absurd, exhausting, and absolutely hilarious. It was a Christmas tradition.
Halloween, however? Damian had point-blank refused to participate in until now.
Jason dropped his book on his chest, smirking. “Zombie assassin. Low effort. Mess some fake blood on your face, carry a sword. Boom.”
“Derivative,” Damian shot back. “Sloppy.”
Steph leaned over the back of the couch, eyes sparkling. “Cereal killer. We glue some knives to a Lucky Charms box, and you carry it around. Classic pun. Very you.”
“You are an embarrassment.”
Cass padded over quietly and held up a simple black headband with cat ears that she appeared to have produced out of thin air. Her expression was neutral, maybe even a little hopeful. Damian hesitated, just a fraction too long, eyes narrowed in consideration. Then his mouth hardened. “…No.”
Tim didn’t bother looking up; instead, he frowned at the chessboard as he considered the move Bruce had just made. He glanced up at Bruce, but the man’s face was poker-blank. Tim narrowed his eyes at him, then looked back at the board. “Go as me. Scariest thing imaginable.”
Damian actually tilted his head, as if considering it. “…Tempting. But no.”
Barbara chipped in. “What about Harry Potter? Or a Jedi? Recognisable, crowd-pleasers, and no one will mess with you.”
“Corporate mascots for greed,” Damian said flatly.
Bruce, who had been silent, finally looked away from the chessboard and made one suggestion. “…Batman.”
The look Damian gave him could have burned Gotham down. “Unacceptable.”
Jason piped in. “Robin? Red Hood, but shorter? Mini-Nightwing?”
Dick made an excited noise.
Damian scowled more. “Redundant. And crass. I am already Robin.”
Alfred, sliding into the room with a plate full of snacks, offered in his most dignified tone. “Perhaps a butler costume, Master Damian?”
Damian paused.
“To impersonate you would be presumptuous,” he said at last, voice measured. “I would never mock your station.”
Alfred inclined his head, the faintest hint of amusement tugging at his lips. “A wise answer, young sir.”
Jason, from across the room, immediately snorted. “Translation: you’d look adorable in a tux and you know it.”
Damian threw him a glare sharp enough to cut glass.
The room exploded with laughter. Dick actually slid off the couch. Steph wheezed. Even Jason had to wipe tears from his eyes. Damian’s scowl grew darker with each peal of laughter until, with a dramatic snap of his blanket cape, he stormed out of the room.
“Useless!” he barked as he vanished down the hall, ignoring Dick’s calls for him to come back. “All of you!”
The library was quiet in comparison. Damian found Duke slumped in one of the window alcoves, earbuds in, an open notebook in his lap. He was tapping a pen against his lips, furrow in his brow, as he considered the half-written poem in front of him. The page was covered in scribbles and half-blacked-out lines. The smell of books hung heavy in the air.
“Thomas,” Damian said sharply. “Assist me.”
Duke looked up, tugging one earbud free. “Uh… with what?”
“Drake is useless, Father mocks me, Todd insults me, and the others are clowns.” Damian planted himself squarely in front of him, chin raised. “You are the least ridiculous. Therefore, you will help me select an appropriate disguise.”
“Um. What for?”
“For the acquisition of confections under false identities.”
Duke made an ‘o’ of realisation with his mouth. “You’re asking me about a Halloween costume?”
“This is not a trivial matter.” Damian’s voice was iron. “My comrades—Rina, Skylar, Theo, Marcus—will all be there. This is my first such gathering. I cannot afford failure.”
There it was. Not stubborn pride, just nervousness, tucked into the corners of his mouth, the stiffness of his shoulders. Duke softened a little. He flipped his notebook closed and sat up.
“So this is about your D&D crew,” he said. “About fitting in.”
“It’s about winning,” Damian said instantly.
“Right,” Duke said dryly, pocketing his notebook and standing up. “Winning. Okay, soldier. Let me find my keys and steal Tim’s credit card, and then we’ll go raid Spirit Halloween.”
Spirit Halloween was sensory overload: flashing strobe lights, shrieking animatronics, racks of polyester crammed so close together they made claustrophobic aisles. A giant zombie lunged whenever someone passed its sensor. Plastic bones rattled on hooks, a rubber witch cackled overhead, and the air was a mix of cheap fog machine smoke and the faint tang of plastic packaging. Kids tore through the store like goblins loosed on a village, arms overflowing with candy buckets and superhero masks. Their parents, bleary-eyed and resigned, groaned at the price tags and muttered about how the same costumes had been half this price last year.
Duke was on high alert, not just for the perfect costume for Damian, but for trouble. Gotham on Halloween was like tossing a match into a pile of dry leaves; chaos was practically guaranteed. And Halloween stores? They were a breeding ground for it.
The animatronics shrieked, kids darted through aisles, parents snapped at one another—it was a ready-made distraction, the kind criminals loved to exploit. Duke’s shoulders stayed loose, but his eyes tracked the crowd with the instinct of someone who’d been burned before.
Last year, he’d busted an entire chain of pop-up Halloween shops that turned out to be a front for Calendar Man. The guy had rigged his chain of Halloween stores so that on certain dates, anyone who bought a costume or decoration on “sale” would unknowingly take home a booby-trapped item. The traps were timed to go off at exact calendar intervals. Duke had shut it down, but not before spending weeks combing through back rooms filled with rubber masks and clearance-bin skeletons, and tracking down every last one of the booby-trapped items. It had taken forever.
So yeah. He wasn’t about to let his guard down. Not in Gotham, not tonight, and especially not while babysitting a Wayne with the impulse control of a caffeinated crow.
Damian moved through the chaos like a commander inspecting fresh recruits. His arms were folded, his expression severe, as if the polyester horde arrayed before him had personally offended his honour.
“These so-called ‘ninja’ outfits,” he scoffed, plucking one from a rack by its flimsy hood. The fabric sagged sadly in his grip. “A disgrace. You’d be dead in minutes wearing this.” He tossed it back with a flick of disgust that nearly hit a passing six-year-old in a Flash mask. The child stuck out his tongue at him. Damian glared until the boy fled.
“This cape—” Damian snatched one up and held it against the light, the fluorescent glow revealing seams and loose threads. “—is insultingly short. It wouldn’t even conceal a dagger.”
He grabbed a plastic trident, gave it an experimental shake, and frowned deeply. “Weight distribution is wrong. Hollow plastic. Useless.”
Duke followed a few steps behind, biting down on the inside of his cheek to keep from laughing. “You know, costumes aren’t supposed to pass a weapons inspection. They’re supposed to be fun.”
Damian turned a sharp look on him. “Everything is tactical analysis.”
They passed a wall of vampire teeth and fake blood. Damian picked up a blister pack of fangs, considered it for a few seconds, and then grimaced. “Theo will undoubtedly choose these. I cannot copy him. Duplication is dishonourable.”
“Dude, it’s not dishonour. It’s Halloween.”
“It is always dishonour,” Damian said, voice firm.
Duke picked up a samurai costume from the rack next to him and held it up for Damian to see. “What about this one?”
Damian plucked the samurai costume from Duke’s hands, unfolding the flimsy fabric with a scowl and inspecting it.
“This,” he declared, “is not even close to ō-yoroi armour. No lamellar plates, no proper sode for the shoulders—just painted cloth pretending at steel.”
He flipped the plastic helmet over with disdain. “And this? A child’s toy. A true kabuto was made to turn blades and deflect arrows. This would shatter if struck with a spoon.”
With a sharp flick, he shoved the costume back onto the rack. “Pathetic. A disgrace to a noble warrior tradition.”
Duke straightened the costume on the rack and raised an eyebrow. “Right. So… not polyester samurai. Got it. Want me to check if they sell actual forged steel in the kids’ section?”
“Tt.” Damian’s glare was sharp. “Do not mock me, Thomas. I am taking this seriously.”
He muttered as they continued, his tone like a chess master plotting moves three turns ahead. “Rina favours wizards. But I cannot wield a foam staff without betraying the art of weaponry. Skylar prefers cats. That option is beneath me.” He sneered at a rack of headbands with twitching ears. “Marcus will mock me if I look unserious.”
“You could be Alfred the Cat?” Duke suggested, holding up a pair of black cat ears that moved from the rack that Damian had just been staring at. “You’d look cool. Look, the ears move and everything!” He popped the cat ears on his head to demonstrate.
Damian squinted at him. “No. Take those off, you are making a fool of yourself, Thomas.”
Duke grinned and removed the cat ears, sidestepping as Damian brushed past a row of inflatable dinosaur suits. He stopped to eye one, unimpressed. “This beast is extinct. A mockery of prehistory. Its proportions are inaccurate.”
A toddler in the same costume waddled by, tail bouncing. Damian frowned after him, clearly offended. The toddler tripped, fell, and promptly burst into tears.
Damian muttered, “Unfit for battle.”
“Damian. He’s four.”
“Tt. I was slaughtering enemies at four.”
Duke grimaced.
Damian didn’t notice, too busy glaring at a rack of food costumes—hot dogs, doughnuts, bananas, and several more.
Duke, trying to steer him away from the food, pulled a few things off the racks as they walked.
"What about this? Pirate. You get a hat, an eyepatch, and a plastic cutlass. Pretty swashbuckly."
Damian gave him a withering look. "A glorified thief. I will not debase myself."
Duke rolled his eyes and held up a ghost sheet with two holes. "Simple, classic. Everyone loves a ghost."
"I refuse to be mistaken for laundry," Damian replied, shoving it back onto the rack.
Next, Duke pulled down a plastic superhero mask. "Fine. Superhero. Not Batman. Like, Spider-Man or something."
Damian took one look at the moulded red plastic and sneered. “An arachnid that quips instead of kills? Laughable. A predator that refuses to consume its prey is no predator at all.”
Duke snorted. “You do realise he’s fictional, right?”
“All the more pitiful,” Damian said, pushing past him. “I will not shill for another corporation. Especially one that cannot depict a competent hunter."
Duke groaned. "You are impossible."
He tried again as they moved further down the aisle, lifting up a cowboy hat and toy lasso. "Okay, hear me out: cowboy. You like horses. It fits."
Damian sniffed. “Romanticised nonsense. They were ranch labourers, not warriors. Half-starved men chasing cattle across barren land. This hat provides no protection from blades, and this—” he flicked the lasso so it spun limply “—is hardly a weapon. A true horseman was a Mongol, an armoured lancer, a knight. Not… this.” He shoved the lasso back onto the shelf and handed the lasso back to Duke with a grimace. “A caricature for tourists.”
“... right. Noted.” Duke sighed, putting the lasso back and wondering if they’d ever find something that met Damian’s impossible standards.
A few steps later, Duke pointed toward a sparkly vampire cape. "Classic vampire? Cape, fangs, drama. Easy win."
Damian scowled. "That is simply Grandfather. I will not imitate him."
And then he stopped. There, hanging on the rack under a flickering light, was a child’s knight costume: a plastic breastplate moulded with fake musculature, a foam sword stuck through loops, and a scarlet cape that glittered faintly under the harsh fluorescent glow. Compared to the neon wigs and zombie masks surrounding it, the costume looked almost regal.
Damian stared at it as though he’d stumbled upon the Holy Grail. Slowly, reverently, he lifted a hand and touched the plastic chestplate.
“At last,” he whispered. “Noble. Dignified. Accurate.”
Duke raised an eyebrow. The “armour” sagged on its hanger, held together by nothing more than Velcro straps. “That’s hollow plastic, man.”
“It is a symbol,” Damian said, voice low and almost reverent as he unhooked it from the rack. He held it against himself with the solemnity of a knight taking his oath. “A warrior’s garb. I will do it justice.”
Duke scrubbed a hand over his face. “Yeah,” he muttered, already dreading what came next. “Sir Damian of Aisle Seven, terror of the clearance rack. This is gonna be a nightmare.”
Back at the Manor, Damian wasted no time in “improving” his find.
Duke walked into the foyer to find him clanking across the marble floor, real chainmail draped over his shoulders with the flimsy plastic breastplate strapped on top. Every step echoed metallically through the hall.
“You’ve got to be kidding me.” Duke groaned, looking around for someone else to deal with this and finding that everyone else seemed to have conveniently disappeared. “You’re not trick-or-treating in forty pounds of armour.”
“It must be authentic,” Damian replied without hesitation. He lifted his chin with knightly gravity.
“Nope. Strip it. Right now.”
Damian scowled and begrudgingly removed the chainmail.
An hour later, Duke caught him with a gleaming longsword in hand. The foam sword lay discarded on the floor like trash.
“Damian!” Duke nearly choked on his tongue. “You cannot bring a real sword to trick-or-treating.”
“A knight must bear arms.” Damian replied, voice low and reverent. He tested the blade’s balance, utterly unbothered.
“A knight also doesn’t get arrested for brandishing a deadly weapon in public!”
Thirty minutes later, Duke found him in the east wing, crouched in front of an armour stand and fiddling with its boots.
He sighed heavily and dragged a hand down his face. “Damian.”
Damian jumped, spinning around and straightening up like his army sergeant had just snapped his name. “Thomas.”
“What are you doing?”
“...polishing the boots.” Damian said stiffly, sliding half a step to block the clearly unbuckled straps.
Duke arched an eyebrow. “Uh-huh. Wow. Yeah. Totally convincing.”
He gently grabbed Damian by the shoulder and frogmarched him back to his bedroom, ignoring his spluttering protests—only to find an entire dragon’s hoard of medieval armour and weaponry organised neatly across his bed, scavaged from around the Manor.
Duke let out the heaviest sigh of his life. When he’d agreed to help Damian pick out a Halloween costume, he hadn’t expected it to involve single-handedly stopping him from looting Wayne Manor’s entire antique collection.
Later still, Alfred discovered Damian in the study, carefully polishing an antique breastplate liberated from a display stand in the hallway outside. The boy’s expression was solemn, devout, as though preparing for battle.
He had, it seemed, successfully given Duke the slip, which explained why the young man was currently storming through the Manor, calling Damian’s name with the air of someone rapidly approaching a nervous breakdown.
“Master Damian,” Alfred said, perfectly calm, “I would appreciate it if you refrained from dismantling the household artefacts to enhance your costume.”
“It is not a costume.” Damian declared. “It is a proving ground.”
“Regardless,” Alfred replied, not missing a beat, “the armour stays.”
The cycle repeated itself endlessly. Every time Duke confiscated something, Damian emerged with something new.
“Didn’t I say no gauntlets?” Duke barked when Damian came clanking down the stairs again.
“These are vambraces,” Damian corrected, tone prim and superior. “Entirely different.”
It finally ended when Bruce stepped in, a massive hand landing on Damian’s shoulder.
“Plastic,” Bruce said firmly. “Or you don’t go.”
Damian’s jaw tightened, eyes flashing with indignation—but he obeyed. Barely.
When Damian finally came down the grand staircase, the family actually went quiet. His outfit was a strange but striking compromise: the plastic breastplate sat snug over his tunic, but his cape was a true Wayne heirloom, heavy and dramatic as it swept behind him. His toy sword looked almost noble in his grip, and Duke had spray-painted his gloves silver to soften the blow of confiscating the real gauntlets.
He looked both like a child playing knight and like he truly believed he was one.
Dick clasped his hands together. “My little gallant knight in shining armour!”
“Retract that immediately.”
Jason snorted. “Needs more blood. Maybe an eyepatch.”
“Silence, Todd.”
Steph wiggled a glitter canister threateningly. “Glitter sword. Come on, it’d be amazing.”
Damian’s toy blade was in her face instantly. “Touch me and perish.”
Cass studied him seriously, then gave a slow thumbs-up. Damian blinked, then returned the gesture just as solemnly.
Tim smirked. “You look like you escaped a Renaissance fair.”
Bruce said nothing, but the faintest of smiles touched his lips.
Alfred bowed his head, eyes kind. “Quite distinguished, Master Damian.”
Duke lifted his phone to snap a picture. “For the scrapbook. Promise I won’t share.”
The group chat pinged three seconds later. Damian’s furious growl echoed through the hall while Jason doubled over laughing.
The October air was crisp as the car waited at the foot of the Manor’s long drive. Fog clung to the ground, and the headlights cut sharp beams through the mist. Damian stood at the door, plastic sword in hand, cape swaying dramatically in the light wind.
“I embark now,” he said, chest puffed out, voice steady as a commander’s. “This is reconnaissance. If successful, it may be repeated.”
“Good luck, little knight!” Dick called from the doorway.
“Loot all the candy!” Barbara added, grinning.
“Perish,” Damian muttered, but there was no heat to it. If anything, his eyes sparked with something close to excitement. He turned toward Duke and solemnly saluted him. “You have my thanks. Others would have sabotaged my efforts. You understood the mission.”
Duke grinned at him. “So you’re saying I helped you land the perfect Halloween fit?”
“Precisely. This costume is without flaw. Adequate tribute will be arranged.”
“You’re welcome, Damian. Any time.”
Bruce watched silently, expression softer than usual. Alfred murmured about preparing cocoa for when the boy returned. Cass slipped closer to the window for a better view, while Steph and Jason jostled each other to peek.
Duke leaned against the frame (Bruce beside him), arms crossed, smiling faintly. “Kid’s gonna crush it.”
At the end of the driveway, four small figures waved at Damian enthusiastically from by the car they were standing next to. A wizard, a cat, a vampire, and a miniature Batman.
Damian strode towards them, cape billowing dramatically.
Marcus, mini-Batman, pointed at Damian’s breastplate, “Hey, Damian! You look awesome!”
Theo, the vampire, hissed dramatically, exposing bloody fangs in his mouth, then said, with a lisp caused by his fake fangs, “Your costume is so cool! Also, my mom got big candy buckets for us all! This is yours!”
He held out an orange, pumpkin-shaped bucket for Damian.
His mum, waiting in the car behind them, waved at Damian through the windscreen.
Damian took the bucket.
Rina, the wizard, punched him in the shoulder, “Looking good!”
Damian’s chest swelled at the praise from his friends.
Skylar grinned, already opening the car doors and scrambling in. “C’mon, guys! We'd better hurry if we want to get the good candy from the big houses!”
Damian nodded solemnly in agreement, “Tonight, we claim tribute in sweets. None shall stand in our way.”
His friends erupted into cheers, and together, they clambered into the car and set out to adventure into the night.