Disclaimer: I do not own Justice League or Ben 10. Which is why I like setting farm animals on fire.

OK, this tale was mostly inspired by Agent-G's fanfic "Justice League: The Spider". It's an amazing story, and you should read it after you're done with this one. Or before reading this, your choice.

Anyway, this begins a few years after "Ben 10: Ultimate Alien", so Ben is eighteen.

It also begins at the beginning of season 3 of JLU.

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Chapter 1: Second Chances

This wasn't what he wanted. This wasn't how it was supposed to be. He had been a hero, and for what? They were dead. All dead. Mom, Dad, Grandpa, Aunt Lily, Uncle Frank, Kevin, Gwen, Julie...

"Why me?" the eighteen-year-old Benjamin Tennyson asked, the tears streaming down his face. It was around midnight in Bellwood, and the smoke was still visible on the horizon. Ben was seated on the ledge of a twenty-story building, his legs dangling off the side. While his clothes were unscathed, his body was covered in bruises and cuts.

Ben wiped his tears on the sleeve of his emerald jacket. Unfortunately, he used his left arm to do it, and he froze upon seeing the cursed device on his forearm.

The Ultimatrix glowed green in the dark, almost as if trying to reason with Ben. But it wasn't going to happen. Ben had made up his mind on what he wanted to do.

Eight years ago, he had been given the original Omnitrix, and he had loved it. He had become a hero, saving the world and even saving the galaxy. He had fought villains both alien and human. Animo, Hex, Sixsix... And, of course, Vilgax.

But after that summer, Ben wanted a normal life, and he had the alien watch removed from his wrist.

Five years later, Ben took on the role of hero once more, putting the Omnitrix back on to investigate an alien invasion. Ben soon became the savior of the universe, stopping the Highbreed from annihilating all life.

Then Vilgax returned, and Ben lost the Omnitrix. However, he gained the Ultimatrix, and he managed to get rid of his squid-faced archenemy.

A year after that, his secret identity was blown by a little kid who idolized him, and then came the world's biggest pain in the ass: Will Harangue, the reporter who hated Ben for no goddamn reason other than fear.

However, Ben put up with it for three years, still battling enemies old and new, and the public soon backed him up. The teenager was amazed how things changed. His old rivalry with his cousin soon became a close family bond, one of his oldest enemies became one of his best friends, and he actually managed to get himself a girlfriend. Things were going perfectly...

Why did this have to happen? Ever since he had gotten the Omnitrix, Ben had used it for good. He had saved the entire universe multiple times. He had given up so much in the pursuit of justice... But now he had paid the ultimate price.

Even if his body still cried in pain from the battle, he didn't care. It was the mental pain that truly broke him, not the physical pain.

"I can't do this. Not anymore," Ben muttered to himself. What was there to fight for? What was there to live for? Azmuth could have his godforsaken watch back. Ben didn't want it anymore.

The last of the Tennyson family stood and looked down at the pavement below. He would be meeting it up close and personal real soon. The hero known as Ben 10 closed his eyes and toppled forward, the air hitting his face as he prepared for oblivion.

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Inside the newly-built Justice League Watchtower, six well-known heroes were in their meeting room, discussing their plans for recruitment. They were expanding the League, bringing in more firepower to help combat the rising number of villains on the planet. The members were currently going over a checklist of potentials.

"Well, what about this Green Arrow guy? He looks like he has some skill, and he seems to have the whole 'Robin Hood' thing going for him," John Stewart suggested. "I'm not sure he's someone like us. We fight large threats like aliens and supervillains. This guy stops bank robberies and convenience store hold-ups," Flash said, adding his view to the discussion.

"So, he's a maybe. Personally, I think Kara is ready," Superman suggested. Half the table winced, causing the Man of Steel to roll his eyes. "I know, I know, but she's improved. With a little team experience, she could be very good," he pointed out.

"Well, there's always the chance that something crazy happens and we get a new recruit by complete accident," Flash suggested, hoping to cheer up the group. The six of them had been a little saddened since the whole incident with Hawkgirl. Flash and Green Lantern had been affected the most by the whole ordeal.

It was in that moment that a bright flash of light appeared above the heads of the group, and a figure landed on their table as the light died down. The six heroes jumped out of their chairs and prepared themselves. "Um... Is this a sign?" Flash asked upon seeing their surprise guest clearly.

Ben Tennyson groaned and rolled off the table. Since he was in pain, still covered in cuts and bruises, and still wearing the Ultimatrix, he guessed he was definitely alive.

Damn. I wonder if Azmuth had something to do wi-, Ben's thoughts were cut off as a figure grabbed him from behind. An arm covered in a tight gray outfit was wrapped around his throat, causing him to gasp for air.

"Who are you? Where did you come from?" a voice growled from behind him.

At that moment, something inside Ben Tennyson snapped. All the pain and grief he had experienced over the past few hours suddenly bubbled up, filling the legendary hero with an inhuman rage. Someone actually wanted to take him on? Oh, he'd be happy to oblige.

Remembering what Gwen told him about breaking grips, Ben did a quick combination of an elbow to the stomach (knocking the air out of Batman's lungs), a kick to the knee (making Batman lose his choke hold and fall to one knee), and twisted around to deliver a left hook to the dark knight's face.

As Batman hit the ground, Ben jumped over the table and ran through a door out of the room.

Diana ran over to Batman, who seemed surprised by the beating he had received. "The kid's been trained. Didn't see that coming," he said, wiping blood off of his lip.

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Ben Tennyson charged down the hallways, making sure he didn't run into unexpected company. However, it appeared that the space station was almost completely empty. "Come on... Where's the exit in this place?" he muttered as he turned another corner.

His run through the halls was stopped when he found a window. A window that showed the dark void of space.

Seeing the darkness of the galaxy brought back memories of old adventures, such as the fight with Ghostfreak, the test for the Plumbers Helpers, and the fight with Ragnarok (though Ben technically wasn't there for that one).

Ben sighed and leaned on the glass, his adrenaline rush fading instantly.

"You don't seem too surprised to find yourself in space," a voice behind him said. He turned to see a green-skinned man phase through the wall. Ben instinctively lifted his arm that had the Ultimatrix on it.

"I've been in space more times than you'd believe," Ben growled, readying himself for an attack. However, the green man remained still and resumed speaking.

"I sense that you speak the truth. I also sense a great deal of pain coming from you," J'onn noted, scanning the boy's mind. At that moment, the other five founding members appeared from either side of the hallway, effectively trapping Ben.

"I lost everything I loved in a single moment. Wouldn't you feel the same way?" Ben growled, his eyes never leaving the martian. J'onn understood what the boy meant; he too had lost everything he loved, thanks to the invaders.

Superman and Batman also felt that pain, having both lost their family in one single instant. "You are right. I have lost everything I loved, and I felt the same pain you do," J'onn said quietly. Ben's expression cahnged from angry to surprised. He slowly lowered his left wrist.

"You're exhausted. Rest, and we'll talk later," J'onn said, his eyes glowing for a split second. Ben blinked in surprise before his eyes rolled into the back of his head and he tumbled onto the ground, asleep.

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In the medical ward, the six heroes were checking over Ben's health. After removing his shirt and jacket, the team discovered that he had numerous cuts and bruises all over his body, some fresh and some old.

"This kid's had a hard time, that's for sure," John Stewart noted, running his eyes over a large scar that ran down Ben's right shoulder.

While Diana and Batman were running the medical systems, J'onn was scanning the boy's mind. "His name is Benjamin Tennyson," he announced, looking over at his fellow leaguers.

"Alright, we know his name. Now what's with the watch thing?" Flash asked, pointing toward the Ultimatrix. While taking off Ben's shirt, the team had noticed the alien device and tried to remove it as well, to no avail.

"It is a powerful device known as the Ultimatrix, which allows him to transform into alien species and use their abilities," J'onn said after another brief mind scan.

Flash whistled. "Wow. That probably drew some attention," he said quietly. J'onn's eyes glowed again, and he proceeded to go into detail.

"That is correct. Apparently, he found a similar device called the Omnitrix when he was only ten years old. He spent his entire summer vacation traveling the country, fighting human and alien enemies," J'onn explained.

Everyone's eyes widened when they heard that this kid became a hero at age ten. That was, without a doubt, the youngest person in history to become a superhero. He had taken on a huge responsibility at a young age. At the computer, Batman sympathized with the kid. Being forced to grow up before he was ready, whether by taking on a powerful alien weapon or watching your parents get gunned down for money.

"Wait, if he was ten, how was he crossing the country to fight crime?" Flash asked. The others nodded, also curious.

J'onn smiled a little. "Summer vacation. He was on a cross-country road trip with his grandfather and cousin when he found the Omnitrix."

"Makes sense," Superman said, shrugging. J'onn nodded and completed his scan.

The martian tried to keep personal matters out of his scan, but some things were unavoidable. J'onn had seen many villains, such as Doctor Animo, Hex, Enoch, Albedo, Darkstar, Agreggor... and one that standed out named Vilgax.

But the most surprising thing J'onn found was Ben's place of origin. Apparently, he existed in another dimension, one where aliens were very common and this boy was the universe's greatest hero. When J'onn informed the others of this, there was another moment of stunned silence.

"The universe's greatest hero... And he was only fifteen when he did it?" Diana asked. J'onn nodded.

J'onn then wrapped up his tale with the story of Ben's battle with Vilgax where he lost the Omnitrix and gained the Ultimatrix. "That tells us a lot, but he said he 'lost everything'. What did he mean, J'onn?" Superman asked.

"I'm sorry. It's not my place to tell that part. All I can say is that it caused him an enormous amount of suffering. He was actually attempting suicide when he appeared on our meeting table," J'onn said, calmly but firmly.

"Well, if that's the case, one of us is going to have to watch over him and make sure he doesn't try it again," Green Lantern said, looking down at the so-called savior of the universe.

"I'll take first shift," Batman announced. The others didn't know how to react to this, since the dark knight rarely volunteered for things like this. "Okay, we'll go in shifts. And whatever happens, make sure he doesn't escape. We're in the middle of space; he could kill himself by stepping outside," Superman ordered.

The Man of Steel, who had been on the right side of the bed, turned and began to walk out of the room, everyone except Batman following.

However, as Superman walked in front of Ben's left side, a voice behind him said "UNKNOWN DNA DETECTED. SCANNING."

Superman turned as a yellow light erupted from the Ultimatrix and began running up and down his body. He was about to ask what was going on, but, after a few seconds, the light disappeared and the Ultimatrix went back to being normal. "Something tells me that things just got more complicated," Green Lantern muttered.

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Okay, I know this chapter was short, and there were no alien transformations, but I'm making up for that next chapter, I promise. I hope that little twist with the scanning was worth it, at least. Next chapter, Ben has to deal with the full grief over his dead loved ones, and he must decide what he will do in the future. So keep following my story, and reviews are appreciated.

Note: Like I said, this story was inspired by Agent-G's "Justice League: The Spider", so a few things might seem very similar. However, the Ben 10 part allows me to add my own plot ideas, so don't worry about me 'ripping off' Agent-G, because I wouldn't do that to a fellow author.