He joined the team two weeks after Superboy, the Justice League bringing him in this time.

"Come on," Black Canary sighed to herself, watching as Superboy sparred against Robin. "It's like he's not even trying..." She looked up in surprise when she heard a crash and saw a crater in the ground where the clone smashed his fist. Steely blue eyes met hers, anger rushing through them, and it was then that she remembered that the boy had super hearing, "Superboy-"

"I've heard enough," He stopped himself, storming out of the training room. He ignored Robin and Wally's questionings, entering his room and slamming the door shut. He marched over to his bed, sitting down heavily, and looked down at his hands. He clenched them, feeling the strength running through them. He glanced up in confusion when he heard an unfamiliar heartbeat, followed by frantic foot falls. He stood up and opened his door, nearly falling back in surprise when a blur shot inside, "What the-"

"Shh, he'll hear you!" The person shot forward, covering the clone's mouth with his hands.

Superboy blinked, studying the stranger in his room. He had windswept black hair and tan skin. He wore a pair of pitch black goggles, somehow making it look good. He had on a black sleeveless shirt with the same colored cargo pants and boots. He had on finger-less gloves like himself and a couple of leather cuffs on his arms. "Who are you?" He asked bluntly, moving the person's hand away/

"Um, I shouldn't say right now," The stranger shifted from foot-to-foot. "Superman might hear."

"Superman doesn't come to the mountain," Superboy said, feeling annoyance at the name mentioned. "He won't hear you."

"Oh," The person stepped back, taking a look around the room. "I'm still not sure I should say my name. Batman is kind of sensitive about that stuff," He huffed at that part. "I swear, guy will never let me do my own thing."

"Wait, Batman? How do you know him?"

"Oh, we're old friends," The guy shrugged, a light grin making it's way on his face. "I help around his place when he's too busy."

"Okay," Superboy nodded slowly, processing the information. "And why were you running from Superman?"

"I'm not supposed to leave the League's care," He seemed to roll his eyes by the tone of his voice.

"Why not? Why are they keeping you..." The clone fished his thoughts for the right words, "Locked up?"

"Well, I'm not... Well. Kind of sick, actually. They get all protective over me and stuff. It's kind of annoying though," The guy huffed, frowning lightly. "I mean, I feel fine."

"Well, no one's coming down here for a while," Superboy shrugged, moving to his dresser. "They're not coming near me for a bit."

"Why? You seem like a pretty cool guy," The stranger grinned, moving to flop down on the clone's bed, getting comfortable criss-crossed. "What happened?"

"I'm making no progress in my training." Why was Superboy getting so comfortable around this guy? There was just something about him that relaxed the clone. "Canary said it was like I wasn't even trying and I... punched a hole in the ground."

"Oh, you're Superboy," The person nodded, rocking back and forth slightly. "The League really likes you. What's Canary doing for your training?"

'The League likes me?' "She's having me spar against my teammates to get used to fighting different people," Superboy shrugged.

"Okay, that won't do," The guy raised an eyebrow when the clone looked over in confusion. "Don't get me wrong, she has the right idea. It's just... She's two steps ahead. Right now, you need to focus on form and control. Having super strength is nice and all but, if you have no form, you're just a kid throwing a tantrum. Talk to Canary about it. That should help your training more."

Superboy went still for a moment, pausing in his action of opening one of the drawers to his dresser. It could help him? "Could you..."

"Could I what?" The kid leaned to the side, trying to look at his face from the side.

"Could you train me?" The clone turned to the other to see his expression and was surprised that the guy wasn't on the bed but standing next to him.

"You don't even know my name," Superboy felt rather than saw the penetrating gaze coming from the goggles. "For all you know, I could be an enemy of the League."

"I can hear your heartbeat," Superboy deadpanned, tilting his head to the side.

"Oh, true true," He nodded, hand on his chin. "Sure, I'll train ya. We'll start next week, though. I gotta make sure Bats and the rest aren't looking for me here."

"So, are you just Batman's friend?"

"Well, I mean, kind of? I lived with him for a month or two when I was homeless," The guy shrugged, not noticing the clone's wide eyes. "Before that, I kind of just lived on a bus, traveling around whenever I could."

"So, you have no home?" The super was shocked, looking at the guy more closely. No wonder the guy got sick sometimes. He must've had no protection against any sickness going around.

"Nope," The other gave a grin, seeming unconcerned with the news. "But that's besides the point. I lived with Batman for a month or two, got to know his little protegee, Robin. He was such a sweet kid. I helped around the place and took care of Robin when he was sick or injured while Bats went to raise Hell to the kid's attackers."

"Huh," Superboy opened his dresser drawer, pulling out a pair of sweats and throwing it at the other. "Here, wear these."

"Wha?" The guy caught the fabric in surprise, arching an eyebrow at the clone.

"Well, you need a place to stay, right? You can stay here. No one comes in my room. I can set something up for you to sleep on."

"Oh, I can stay in the closet," He grinned brightly, revealing pearly white teeth. "What? It sounds weird and all but I've seen the closets in the mountain. They're huge. Plus, if someone does come in, they don't see me hanging around or see any of my stuff."

"Alright," Superboy shrugged. "I think I have an extra bed or something. What do I call you?"

"Huh?" The guy tilted his head in confusion.

"Well, I don't know your name. I mean, what can I call you if not by your real name? And how old are you?"

"Oh, um... The League calls me Core sometimes and I'm nineteen," The stranger shrugged.

"Core? Why?"

"I don't know. They said I 'hold them together' or some crap like that. I'm the 'core' for the League. Green Lantern calls me a human lantern or something like that."

"Alright, I can call you that," The clone nodded. "Let me set up your, uh, bed."

"You are more trusting than I thought," Core laughed, shaking his head. "Here, let me help."

"You seem happy," Wally said when he got in the living room in the morning, looking at the super. "Why are you happy?" His face flushed when the clone raised an eyebrow at him, "Not that you can't be happy. It's just-"

"Recognize Batman B01."

The two looked over at the Dark Knight, Kid Flash grateful for the interruption. The man strode over and the rest of the Young Justice came to see what the man had to say.

"The League is searching for someone," The Bat began, studying the children.

"Who is it?" M'gann wondered, tilting her head in curiosity.

"We call him Core."

"Core?" Robin perked up before he grinned brightly, something that Superboy realized the boy must've gotten from Core himself because it looked familiar. "Wait, you lost him?"

"We did not lose him," The man aimed a Bat Glare at his protegee. "He managed to run away."

"Who's Core?" Wally asked, scrunching his eyebrows together.

Superboy looked over at the speedster with curiosity. Shouldn't he know who Core is since he's the closest to Robin?

"Core's this really cool guy. He lived with Batman and I when I was four. He was really cool. He was, what, twenty when we saw hm?"

"Nineteen, actually. He managed to escape the League and now we can't find him. We sent Superman but he said he can't find him."

'Yeah because he won't come near the mountain,' Superboy thought before he realized something. 'Wait... If he was nineteen when Robin was four, shouldn't he be twenty-eight now? I'll have to ask him later...'

"If you find him, contact me. Do not engage him. He won't attack you but he acts on self defense," Batman said, turning and striding out.

"I made cookies," M'gann said after a moment of silence, motioning towards the kitchen, and everyone but Superboy followed her.