Disclaimer: I do not own any characters, ideas, or products of the Justice League Unlimited or Young Justice. They belong to their respective owners.

Summary: In this story, the team of sidekicks from the Young Justice universe encounter the Justice League from the Justice League Unlimited universe who don't have sidekicks or proteges. See the reaction of the League as they deal with their young legacies and the adventures they share as the young sidekicks adjust to a world without sidekicks.

Author's Note: This is just a little side story, something to give me a small break while writing the "Once A Hero, Always A Hero" crossover. I am pretty sure this story will be easier to write.

Author's Note #2: Young Justice characters will be at the point where it is a year after Season 1 ended. Team will consist of Robin, Kid Flash, Aqualad, Superboy, Miss Martian, Artemis, and Zatanna. (I did not put Rocket in because well...I don't know anything about her.) Justice League will almost be at the beginning of Justice League Unlimited. Before the League officially starts up with all the additional heroes.

Chapter 1: That Was Unexpected

Batman's fingers rapidly glided over the computer console, his eyes fixed on the giant display screen of the new monitor room, giving the whole station one last check through. With the improvements made to the new Watchtower, there was so much more maintenance to be done. Added docking bays for the number of Javelins they had added to the Watchtower, the number of living quarters added for the increased amount of members, locker rooms, improved training facilities, storage rooms, and even fusion energy generators for the Watchtower's defenses, not to mention the new teleportation system.

"Everything coming together alright? You've been up here all day and night. Should I be worried?" Batman didn't even acknowledge Superman as he landed down next to the Dark Knight. When everything on the screen flashed green, giving a positive beep of approval, a smirk appeared on Batman's lips for a brief moment.

"I guess that answers that question."

Flash zipped up next to Superman, placing his arm nonchalantly on the Man of Steel's shoulder, "I love what you've done with the place Bats. Real homey, you know?" He looked around for a few moments before rubbing his chin, "Is this place bigger, or is that just me?"

Green Lantern hovered down from above, the familiar green energy of his ring surrounding his body as he touched down on the platform next to Flash, "It's not just you, I've noticed it too. You added a lot of things, didn't you? It's certainly larger and has way more equipment than our last Watchtower did."

When Flash and Superman looked at Batman, his expression hadn't changed. He still had that sort of brooding face as he stared right back at the three, "With the discussion of expanding the Justice League we had a few months ago, I had to make a few changes. I predict that with the increased amount of activity and staff the Watchtower will be experiencing, the increased space and equipment will be a very welcome change."

The three heroes glanced at one another, sharing a knowing look. Leave it to Batman to think of everything in just a few months.

Batman turned back to the computer console, once again typing into it as the screen blinked rapidly, pulling up a long list of names. Each name had a photo of the hero next to it along with a short description, "This is the list of names of some of the heroes everyone has been able to contact and suggest with the utmost scrutiny."

As the list slowly scrolled upwards along the twenty or thirty names, Flash scratched the back of his head when he caught the name of one in particular, "Hey Bats, I know we discussed this at length before but... The Question? I mean, sure the guy practically knows everything about anything and is a pretty good information gatherer... But you know he's kind of...paranoid."

At the last word, everyone looked at him funny except Batman, who sent the speedster a small glare. Flash looked at each of them quickly before scratching the back of his head again, "Uh...not that there's anything wrong with paranoid. Except...you know. He questions everything, true to his name, and he's all jittery and...kind of creepy."

Batman resisted the urge to sigh before he turned his gaze back to the screen, his fingers once again moving over the computer console as a screen with the information on the hero at hand popped onto the screen, "The Question is considered a paranoid conspiracy theorist, but the fact is, he is a vast source of information on a variety of subjects. He has infiltrated and has even obtained data on people such as Lex Luthor. Not only is he an impressive detective, he is also a master in several forms of martial arts. And despite his slightly warped personality, he is a great philosopher and makes good judgments most of the time."

With that, everyone looked back at Flash who gave the three another quick glance before smiling sheepishly, "Okay okay... So now what? We got a response from all of them and they agreed to come and hear us out, right?"

Batman shook his head as he pulled up another screen, this time of a certain archer in green, "Green Arrow has yet to respond to our invitation. So has Hawkgirl."

At the mention of their former teammate, everyone froze except Batman who continued to type on the screen before turning to the three heroes, "I need one of you to go get Green Arrow personally. If he isn't going to answer our call, we'll bring him in ourselves."

Green Lantern frowned, shrugging off his shock from Hawkgirl, "Well if he isn't answering, then he's obviously not interested. Why bother?"

Batman stared at Green Lantern for a few moments before speaking, "I have a few theories on why Green Arrow isn't responding. If I'm correct, several of those theories can be resolved if he just comes up here to see what the League is really about and experience what we really do."

Lantern merely raised a brow at Batman's logic and was about to respond when they felt the station rumble. All heroes looked at one another for a brief moment before Batman rapidly turned to the computer console, bringing up diagnostics of the Watchtower.

"Uh, what was that?" Flash ran up next to Batman, peering down at the Dark Knight.

"I am not sure. There has been no breach in the perimeter. Defenses are green. Nothing is attacking us." Batman's eyes narrowed slightly, "But there are traces of an off world energy..."

Superman stepped up on the other side of Batman, "What sort of off world energy?"

Batman glanced up at the Kryptonian, "The same kind of readings a Boom Tube would generate."

The other three heroes suddenly had determined looks on their faces as they looked up at the screen as well, "Last time a Boom Tube popped up, it was Darkseid paying us an unwanted visit. Do you think he survived?" Flash looked at Batman who was scowling at the screen.

"No." Surprisingly it was Superman who spoke up, "Nothing could have survived that. Not even Darkseid. We checked every inch of what used to be Brainiac's base. We looked for any sign of Darkseid, as well as any piece of Brainiac. There was nothing." He glanced down at Batman who merely nodded.

"Any idea who then?" Green Lantern gestured to the screen.

Batman suddenly turned around, glaring at the open platform, "We're about to find out." As the three heroes turned around like Batman did, a large boom shook the room as it echoed through the room. Green Lantern pointed his right fist at the large glowing gateway in front of them, Flash and Superman taking guarded stances as the air started to get sucked in.

Batman's hand went up to his ear as he pressed the communicator, his eyes never leaving the Boom Tube gateway, "J'onn, it's me. Get down here now."

"What's happening? I just finished installing the equipment in the medical facility, are we under attack?"

"Just get here, now." Batman shut off his communicator as he drew a batarang when he spotted shadowy figures moving out of the gateway. Each of the heroes paused when out popped seven teens, tumbling out of the gateway.

"Well... Out of all the horrible and apocalyptic things I expected to come out of a Boom Tube wormhole, that was not even on the list." Flash straightened up, waving his hand at the teens.

Green Lantern also straightened up, dropping his arm as he eyed the costumes that some of the teens were dressed in. Some looked kind of familiar, especially a certain yellow and red armor with a red lightning bolt on the chest. It seemed like someone had a Flash fixation.

Batman still had his arm up, glaring at the teens who were getting up, "Don't let your guard down, these are not normal kids. They infiltrated the Watchtower with a Boom Tube."

Flash blinked before grinning, lifting his arms up in a shrug, "Oh come on Bats! They're kids, how much trouble could they give us?" As soon as the words were out of his mouth, one of the teens across from the four heroes shook his head of his grogginess. He looked up with wide eyes before a snarl finally left his lips.

Flash's eyes widened in surprise when one of the teen boys wearing a black shirt with Superman's logo printed on the front, cried out in rage and jumped very high up into the air. Moving on instinct, Batman threw his explosive batarang with all his might towards the teen before diving to the right, "Scatter!"

Flash immediately ran right while Green Lantern flew up into the air, Superman right alongside him. Each hero blinked once in surprise when the small explosion didn't even phase the teen, who slammed his fist down onto the ground where the heroes used to be.

Seeing the rather large dent the boy had made into the reinforced steel, Batman's eyes narrowed. Definitely not normal teenagers.

Batman ducked just in time as he heard the swish of an arrow leaving it's notch, an explosive arrow similar to that of Green Arrow's own invention, exploding a few feet away. Batman turned, glaring at a blonde haired archer as she notched another arrow, aiming for him.

A red blur zipped past him and quickly grabbed the girl's green bow, holding it up in the air as he wagged his index finger at her, "Now now, that isn't very nice archer girl. Why don't we all just calm down and..." Flash didn't get to finish his sentence as he experienced, for the first time, a fast punch to his face that he didn't have enough time to dodge. Granted he was caught off guard, he couldn't help the shock going through his mind as he flew back, letting go of the bow he just confiscated.

Batman watched with growing curiosity as a yellow blur, similar to Flash's movements, moved towards Flash and delivered a solid punch to the speedster's jaw. Again, definitely not normal teenagers.

Flash shook his head, looking up in mild shock at the yellow and red clad teen now standing next to the green costumed archer who was picking up her bow.

Meanwhile, the dark haired teen with the S-Shield symbol on his chest let out another cry of rage as he took another big leap towards the hovering Superman, whose eyes widened in surprise as he got body slammed by the teen. Green Lantern, with equally wide eyes quickly recovered from his shock as he pointed his ring at the teen. He gave a sudden grunt as he felt himself being pushed down onto the ground by an unseen force, before finally crashing down onto the ground.

Green Lantern shook his head, looking up just in time to see a dark skinned boy swipe his fists down at him, blue tattoos glowing all over his arm. Lantern just managed to bring his ring up and form a shield in front of himself, the boy's fists making contact with the solid green energy shield. Lantern blinked in surprise when the boy's fists crackled with electricity, causing little cracks all over his shield.

Green Lantern's eyes widened when he saw a green skinned girl hovering in the air a few feet away, her long red hair flowing down her back as she pointed her hands at him. He felt his body lift up into the air. Telekinesis. That explained it.

Without pause, the dark skinned boy took advantage of Green Lantern's moment of surprise to jump into the air, once again bringing his fists down towards the guardian. Reacting quickly, Green Lantern shot his fist out, firing a beam of green energy into the boy's midriff and sending him crashing into the wall, hard enough to knock him out.

The green skinned girl, temporarily losing focus as she watched her friend being blasted away, dropped the Lantern who remained hovering with his own power. Taking advantage of her distraction, Green Lantern shot a blast of energy out and into the girl as well, slamming her back into the metal wall. She yelped as she was blasted before collapsing onto the ground next to the dark skinned boy, lying still.

"M'gann!" Green Lantern turned to see the tall brunette with the Superman symbol stare at the downed girl for a moment before looking at him with eyes filled with rage. He snarled as his hands balled up into fists, "You'll pay for that!" He took another leap, pulling his right fist back as he neared the Lantern.

Suddenly, a blue and red blur slammed into the teen in midair, carrying him through the air for a few moments before slamming him into the metal wall. A large dent was formed as Superman pulled back, his hands on his hips, "You need to calm down."

"Erif niar nwod no pot fo mih!" Superman turned towards the sound of a girl's mystic voice echoing throughout the room. He cried out as large balls of fire crashed into him from above, knocking him down onto the ground.

A girl dressed in a tuxedo with a set of white gloves had both her hands pointed towards the Man of Steel, smiling in satisfaction for a few moments before a batarang suddenly swished through the air and stabbed into the ground under her feet. She looked down and gasped as the batarang beeped before exploding into a large puff of green smoke. She coughed, trying to cover her mouth but had already breathed in enough, her legs wobbling as she felt her consciousness fade before dropping onto the floor with a groan.

Three down, four to go. Batman looked towards the teens still standing. The Flash-Boy was currently in a fist fight with Flash, who was experiencing the surprising ordeal of having to actually block attacks pointed towards him instead of dodging. They were zipping around the whole place, exchanging blows. Batman noted with interest that while the Flash-Boy could land a few blows on Flash, he was still quite a bit slower than Flash himself.

His gaze turned to the green clad archer who was pointing her bow at the two speedsters, her bow whipping left and right as she bit her lip, trying to keep up with the super speed battle.

Deciding to end this little battle, Batman drew a batarang and threw it towards the archer's bow, fully intent on disarming her. His eyes widened as his batarang was intercepted by a red projectile similar to his own explosive discs. His gaze turned to land on the form of a small, dark haired boy sporting a domino mask, his eyes fixed on the dark knight. His mask hid his eyes fully, the white slits the only visible difference from the dark mask.

The boy seemed hesitant, a bit confused as he regarded the Dark Knight. Why, he did not know. And for the moment, he did not care.

Quickly drawing then throwing three explosive batarangs from his utility belt, Batman ran towards the boy dressed in a red, black, and slightly yellow uniform. In response, the lean boy performed a series of back flips as the batarangs exploded one after another in place of where the boy used to stand.

Across the room, the boy with the S-Shield on his chest was throwing fist after fist across Superman's face. Not wanting to hurt the young boy, but finding his strength very surprising, Superman grabbed the boy's left fist with his right hand before grabbing the boy's right fist with his left hand. The boy yelled and growled, trying to pull his hands away in vain.

Superman looked down at the boy with narrowed eyes, speaking in a strained voice, "I am only going to ask you one more time. Calm. Down." the boy looked up at Superman with defiant eyes, letting out another cry of rage as he kicked off the ground with surprising force, pushing Superman back.

As the teen was about to deliver a vicious headbutt to the last Kryptonian, J'onn phased through the floor slowly, his body barely visible courtesy of his intangibility. As soon as he was fully through, the Martian turned tangible once more before reaching out and placing his hands fully on the boy's head, his eyes glowing bright as he pushed one command into the teen's mind with all his might, "Sleep."

The teen let out a cry of pain before moaning, his shoulders slumping as he dropped to his knees. Superman let go of the boy's fists, watching as they limply fell to the ground, nodding at J'onn in thanks.

Green Lantern hated fighting kids, it was hard to blast them with full power, especially when they weren't as durable as some of the bad guys he usually fought. He grimaced slightly as another explosive arrow slammed into his energy shield. Though he supposed he couldn't just stay floating in the air and let himself get shot at, now could he?

Dodging swiftly to the right, Green Lantern thrust his right fist out, firing another blast of green energy at the blonde archer. She performed a barrel roll to the right while notching an arrow onto her bow. She straightened up on one knee, firing the arrow swiftly. Caught off guard, Green Lantern just watched as the arrow opened up, a steel cord firing out and wrapping around his arms. Just as he was about to break free, the cord suddenly charged up and he let out a cry of pain as a surge of electricity covered his body.

Batman, temporarily distracted by Green Lantern's cry of pain, looked away from his own opponent. He took stock of the metal cord around Green Lantern's arms and threw a batarang, the sharp edge cutting through the rope of metal.

The now free Green Lantern didn't hesitate as he formed a green energy fist and shot it out towards the blonde archer, slamming her right on the chin. She yelped and flew back, rolling across the floor before coming to a still.

Hearing the cry of his archer, the Flash-Boy stopped in his tracks, turning around to see her roll across the ground, "Artemis!" He ran towards her, dropping his arms in an attempt to scoop her up. He skidded to a halt when Superman landed in front of him with his arms crossed, blocking the young speedster's way. Eyes wide and mouth falling open he turned around to run the other way when the fist of the older speedster rammed into his face, sending him flying back into the Man of Steel.

Letting out a groan as his head shook from the impact, he blacked out. Flash looked up at Superman with a wink, grinning at their handiwork.

Six down. That left...

Batman's eyes widened as he looked around. He had lost track of the boy he was fighting, his gaze shifting around the room before it landed on the main computer console. The boy had some sort of electronic device on his left wrist, the fingers on his right hand typing rapidly along what seemed like a holographic keyboard. On the small holographic screen displayed above his wrist, was the Watchtower systems.

Batman's eyes widened as he saw a USB cord extending from the boy's wrist to one of the slots on the main computer console of the Watchtower. The five heroes made a move for the boy when he suddenly turned around with a smirk of triumph, holding his hand in the air, "Whoa... Unless you want me to use the thrusters to knock this whole place out of orbit and destroy the generators, I suggest you don't move."

Everyone stopped, eyes wide with the exception of Batman at the boy's words. Flash let out a laugh, his hands on his hips as he grinned at the young boy, "Nice bluff kid, but the Watchtower was programmed and designed by Batman. There's no way you could have-"

The young boy's smirk grew even wider as he cut the speedster off, looking right at Batman as he spoke in an amused tone, "Same system as the Batcave huh, BW?"

Batman's eyes widened for a split second before narrowing into a glare. He held his arm up to the other four, "He's not bluffing. The Watchtower's programming is an almost exact replica of the supercomputer I designed in the Batcave. If he's familiar with it, hacking into the Watchtower's systems wouldn't be that hard."

Green Lantern waved his hand, sparing a glance at Batman, "But how would he know the Batcaves' supercomputer's systems in the first place. He's obviously bluffing!"

Batman glowered at Green Lantern's theory but kept his gaze on the boy, "The fact that he clearly knows who I am and even the existence of a supercomputer in the cave raises a high chance that he is in fact, telling the truth."

J'onn floated down next to Batman, speaking in a quiet tone, "BW... Bruce Wayne. It seems this young man does indeed know your identity, but he could just be a fanatic who managed to deduce your identity."

Batman resisted the urge to growl in frustration, gritting his teeth, "Yes, it is possible. But do you believe that these teens, most with super powered abilities and the fact that they used a Boom Tube to get aboard the Watchtower, are just some fanatic fans? We cannot afford to take the risk that it is also possible that he is telling the truth."

J'onn stayed silent for a few moments before nodding. Batman then spoke up, glaring at the boy, "Alright, you proved your point. What is it that you want?"

The brunette blinked, having not expected that answer but quickly recovered, "First things first, I want you to let us go." Though he was speaking to all them, his eyes were fixed on Batman. His breath suddenly hitched, his right hand moving up to grab his side as he bit his lip. This was not lost to Batman nor Superman as the boy quickly hid his pain, removing his hand, "Second, I want you to stop this repressive regime."

Everyone stood still for a few moments before Green Lantern spoke up, "Repressive regime? What in gods name are you talking about? We are heroes, not conquerors. We haven't repressed anyone! The Justice League is a force of good and protection, not repression!"

The boy seemed to go stock still, his mouth hanging open for a second before quickly closing. He gazed at each of them before quickly typing into his holographic keyboard. The heroes took a step forward but Batman shot his arm out, making them halt in their place. Each of them looked at the Bat in confusion before noticing the boy's activities were being shown on the large computer screen. He was searching through the database, going through their history file before finally bringing up an image of Metropolis in all it's glory, zooming in specifically on the Daily Planet's office floor.

Superman's eyes widened as he saw Lois Lane walk across the large window, talking on her cellphone with raised eyebrows. She must have been talking to a source. Either that or Jimmy by the way she seemed like she was resisting an urge to scream.

Superman narrowed his eyes at the young boy who looked at the Kryptonian with surprise, as if seeing him for the first time. Superman took one step forward, "If you hurt her, I'll make you regret it."

The boy didn't seem to register his threat as his shoulders sagged, as if a weight was lifted off his shoulders, "So we did it...we actually did it. KF was able to fix our..." the boy didn't finish his sentence as he suddenly started to fall forward.

Flash, moving on instinct, zipped towards the boy and caught him. At the same time, Batman dashed for the computer and moved right up to the console. His hands started to dance across the keyboard as he tried to regain control of the Watchtower. He scowled as green images of the boy's face, smirking mischievously, filled the screen.

Taking more time than he would have liked, Batman finally managed to regain control of all the Watchtower's systems, running three more diagnostic tests of the entire Watchtower before he felt satisfied. Turning away from the screen and towards his fellow Leaguers, who were currently laying out the unconscious teens in a row, he regarded these threats carefully.

What were they? Defective clones made by some sinister organization? Aliens from another planet? Were they some strange project made by Darkseid before his demise, come to exact their revenge? None of it made sense. They all seemed confused when they first arrived, a few of them even seemed shaken and weary from battle. Then there was the youngest one's reaction at the end, before he passed out. What was that?

Needing more answers and not having enough information, Batman stood up and made his way towards the group when Flash suddenly spoke up, "Batman, this kid. He's injured, and I don't think it was during our fight. He's bleeding pretty bad from his left side, seems he was wearing Kevlar under his armor but he's been shot in several places."

Before Batman could respond, Superman flew towards Flash, "Get him to the infirmary, now." Flash nodded before zipping away with the boy in his arms, earning Superman a very dark glare from Batman.

"Hostile, super powered beings infiltrate the Watchtower and attack us on sight and you think it's a good idea to give one of them treatment?" Batman spoke in that irritating 'you are stupid and I am right' tone at Superman.

The Man of Steel shook his head, placing his hands on his hips, "They may have attacked us, but they didn't seem to have much of a malicious intent. Besides, they're children."

J'onn spoke up as he stepped up besides Batman, "Correction, they are super powered beings who seem to have remarkably similar powers to our own." J'onn's eyes drifted towards the green skinned girl, his heart giving a slight squeeze at the sight of what appeared to be another Martian.

Green Lantern landed down next to Superman, waving his arm at the unconscious teens, "And you call the attack they made 'non-malicious'? They seemed pretty malicious to me." He crossed his arms, glaring at the downed teens.

J'onn spoke up again, looking away from the green skinned girl, "No, I am in agreement with Superman. While I cannot fully read their minds, I could sense fear and desperation as they fought, not malicious intent."

Green Lantern raised an eyebrow, "They're the ones who invaded us, what were they so afraid of?"

Batman stepped forward, his eyes narrowing, "What do you mean you can't 'fully read their minds', J'onn?"

The Martian looked towards Batman, nodding his head, "During the battle, and a few moments ago, when I attempted to read their thoughts I encountered a powerful mental barrier around their minds. A barrier made specifically to shield them from mental probing or attack. While I can break through it, I fear I might cause permanent damage to their minds if I tried."

Batman glanced at the teens before looking back at his fellow Leaguers, "First things first, we need to secure them in holding cells. Ones strong enough to hold each of them. Which means we'll have to-"

Superman cut him off, shaking his head, "No, we are not going to lock them all up with equipment that should be used to hold each of us. I refuse to put children through that."

Batman stepped forward, glaring at Superman, "If you hadn't noticed, Kent. One of these so called 'children' you are trying to protect almost went blow for blow with you, even if it was only for a few moments. They are dangerous threats, and should be treated as such."

Superman crossed his arms, staring right back at Batman without flinching, "They were just scared and probably confused. They didn't exactly come through the Boom Tube organized, they fell through like they were running from something. You can't blame them for defending themselves."

Green Lantern raised his hand, "To be fair, they attacked us first."

Superman gave Green Lantern a pointed look, "The point is, they didn't come here to attack us. They are just a bunch of scared and desperate kids, from the way J'onn was describing it. So why don't we just wait for them to wake up and talk?"

Batman barely held in his frustration as he spoke in a strained voice, "In case you didn't hear me, these are not 'just some scared and desperate kids'. They are super powered threats who attacked us first, and to some degree, caused us quite a bit of trouble. They should be in holding cells. Right. Now."

Superman and Batman had a silent battle as they glared at one another while Green Lantern and J'onn looked from one to the other. Just as they thought the staring contest would go on for hours, they heard a low groan from one of the teens.

The Flash-Boy slowly sat up, his right knee bending as he rubbed his face with his right hand, "Ugh... I so don't want to do that again... Going up against the League once is enough...but four times... Jeez..."

The boy abruptly froze when Green Lantern cleared his throat, his head whipping up to attention. His eyes widened and he scrambled up, placing his right foot back as he prepared to make a run for it when Superman held out his hand, "Wait! Please just wait. We aren't going to hurt you, we just want to talk."

The Flash-Boy froze in place, his right arm raised and his left arm stretched behind his back. He stared at the four heroes in front of him for a long time, his mind racing and his eyes full of questions. He stood up straight, dropping his arms by his sides as he glanced at his fellow teammates then back at the heroes. Biting his lip and thinking for a minute he nodded, looking at the heroes with uncertainty, "Talk...alright. Talking is good... How should I start?"

Author's Note: This was another story I really wanted to write my own variation on, it seemed like a fun idea to write and I hope it'll be equally loved with my other one. I promise it won't distract me from my first story. And like my other story, Flash is Barry Allen, NOT Wally West.