Summary: Tommy's got a tattoo. Magneto disapproves. Because Tommy's tattoo is an identification number under the label "TEST SUBJECT." And if Magneto had ever fought for anything, it was to keep that from happening to his children or their children.

Numbered

Magneto had his fair share of failures. More than his fair share. In large part because he'd attempted many things that most would consider impossible. Of course not all of them would end in success.

He'd made mistakes. Many, many mistakes. At some point or another, he'd lost every single person he'd ever loved.

He'd been fortunate enough to get some of them back.

Like everyone who's ever lived, he had regrets, but what his greatest regret was, what his biggest mistake was, he would have had a difficult time deciding on it. Especially when somehow, impossibly, everything was going right in his life.

Working with the X-Men, he had hope for the future, both for humans and mutants. He and his son Pietro were on speaking terms again. His daughter Wanda had been found, and her memory had been restored. His grandchildren, Billy and Tommy, had been reincarnated and given new lives, and both of them had proven to be fine, upstanding young mutants.

For the first time in his life, Magneto was able to take joy in all the little mundane things that he had never been able to before. Things like family dinners or walks with his daughter, a phone conversation with his son, or a surprise visit with his grandchildren.

It was on one such visit that Magneto found it: his greatest regret. The one thing that would forever stand out in his mind as his worst failure, even amongst all the other mistakes he'd made, or things he should have done or shouldn't have done. The one thing that he would have given anything, anything at all to change.

The Young Avengers, or what was left of them, were just returning to their base when he arrived to drop in on them. Whatever happened had clearly left them roughed up a bit, but not too much worse for wear. Injuries were limited to a few singes and scrapes. Their uniforms had a few burns and tears in them, and they were all dusted with soot, but they had clearly returned victorious.

"Hello Thomas. William." Magneto greeted his grandsons, levitating himself down slowly so as not to startle them. Granted, the pushy and excitable Patriot, who had been the biggest advocate of keeping Billy and Tommy away from Magneto had quit, and the four Young Avengers who remained had always been among the most tolerant of Magneto, but there was no sense in needlessly provoking feelings of aggression or defensiveness in any other them. "I hope I haven't caught you at too inopportune a time."

"Magneto. Hi," said Billy, looking at him with the awe that always lit up his eyes every time Magneto dropped in on him. Magneto found that quite endearing, even though that same trait in Billy's boyfriend Hulkling was not nearly as tolerable. Hulkling simply lacked the inheritted good looks to be able to pull it off.

"Hey Magneto," said Tommy, and perhaps it was Magneto's imagination, but his elder grandson looked a bit uncomfortable. Distracted.

"Hulkling. It is good to see you again. And Miss Hawkeye, beautiful as always."

The other two Young Avengers greeted him politely and Magneto was invited inside their base.

"You came at a good time, if you don't mind seeing us a little bit charred," Hawkeye told him, ushering him inside.

"Hey guys, I'm just gonna run up and change real quick since I'm kind of a mess," Tommy said, trying to step around Hulkling who was blocking the stairs.

"Tommy! Your grandfather came all this way to see you," Hawkeye chided him. "Sit. Spend some time with him. He doesn't care how you look."

"But I –"

"Sit," the leader ordered.

Tommy's jaw clenched and he looked even more uncomfortable than earlier.

"If there was something else you had to take care of this afternoon, please don't hold off on it on my account, Thomas," Magneto said quickly. "I know I dropped in rather suddenly."

"It's not that," Tommy said, fiddling with his torn sleeve like he was trying to hide the gap that showed off a few inches of skin just above his elbow. "I'd just really rather go change."

"Come on, Tommy," Billy said, slinging an arm around Tommy and leading him to the sofa. "How often do we really get to see our grandfather?"

Tommy muttered something indecipherable but stayed seated.

"Would you like something to drink, Magneto?" Hulkling asked as he peered into their main room's minifridge, always the polite one. "We've got . . . iced tea, Coke, and mineral water."

"Water will be fine," Magneto told him.

Hulkling collected two handfuls of drinks and passed them out to the rest of his team without even having to ask what they wanted, then settled down on the sofa, on the other side of Billy, who sat in the middle.

"What have you children been up to?" Magneto asked, and mentally chided himself when he saw the Young Avengers pull faces at his way of phrasing.

"We teens just finished dealing with some two bit new wannabe villain who was trying to torch Central Park," Hawkeye answered.

Magneto raised an eyebrow. "I thought that it rained this morning, and early this afternoon as well."

"It did," Billy told him. "Needless to say, the guy's plans didn't go so well."

"There was lots of smoke, but nothing really burned," added Hulkling.

"Except when he turned his flamethrower on us," Billy reminded him.

"But we didn't burn. We had to dodge some shrapnel though."

"Tommy needs to practice his dodging," teased Billy. "What were you doing, trying to catch all the pieces in midair?"

"Something like that," muttered Tommy. He was still fiddling with the tear on his sleeve, holding the two edges together like he thought that keeping them that way long enough might rejoin the fabric.

"Thomas? Are you feeling ill?" asked Magneto, feeling a spike of concern. Usually Tommy was much more attentive when Magneto was around. He was never particularly talkative, at least not in Magneto's presence, but always before Magneto had the feeling that Tommy was hanging on to his every word. He'd gotten a feeling of quiet respect. Now it felt like Tommy was trying to hide something from everyone, but especially from him. Something that he was likely worried would make him look weak. Had he been injured in their earlier scuffle?

"I'm fine," said Tommy, looking up with a little bit of surprise. "Thanks for asking, though."

"Are you certain you feel well, child?" Magneto asked again, not convinced.

This time a slight smile actually crossed Tommy's face. "Yes. I'm fine, Grand- er, Magneto." Neither Tommy nor Billy seemed comfortable calling him Grandfather yet, but Magneto hoped that in time, they would. "I'm not injured, or sick, or anything."

Then Tommy seemed to forget about holding his sleeve together and reached for the can of Coke Hulkling had left for him on the end table between the sofa and the chair where Magneto was sitting. The two edges of the fabric stretched apart at the movement, and Magneto got a glimpse of what Tommy had been trying to hide.

Without even being conscious of moving, he stood and seized Tommy's arm, knocking his bottle of water onto the floor, where it shattered.

"What the?" yelped Tommy, dropping his soda can to join the mess Magneto had just made. "Hey! Let go!"

"What? What's going on?" Billy was staring at them in surprise.

Hulkling looked slightly alarmed, and put a hand on Billy's shoulder, ready to pull his boyfriend behind him if need be. Hawkeye looked just as surprised as everyone else, and was the first of the other Young Avengers to get to her feet, after Tommy.

"What is this?" Magneto thundered, clenching Tommy's arm, hard.

"Nothing! Let go of me!" shouted Tommy. He tried to yank his arm away, but Magento's grip was like iron.

"What are you doing to him?" demanded Hawkeye.

"What's going on?" Billy asked again.

"Let go!"

"Magneto, you need to let go of him, right now," warned Hawkeye.

"Who did this to you?"

At the realization that Magento had spotted something wrong with Tommy, something that none of them had seen, the other Young Avengers immediately ceased regarding Magneto as a threat.

"Is something wrong with Tommy?" Billy asked, standing as well and putting a hand on Tommy's shoulder.

Tommy flinched away from him and tried again to pull out of Magneto's grasp. "It's nothing. Let me go, Magneto."

"It's not nothing," growled Magneto. "I'm only going to ask one more time, Thomas. Who did this to you?"

"What is it? What's wrong with him?"

The other Young Avengers crowded around trying to see. Once they did, they all fell silent.

Because tattooed on Tommy's left arm, several inches above his elbow, visible through the hole in the fabric were the words and numbers "TEST SUBJECT 14.23.07" right above a barcode.

"They gave it to me in juvie," Tommy said in a voice that was soft but still laced with anger. When he tried to pull his arm away again, Magneto let him. "Thanks for showing everyone. Really. I can't thank you enough for that."

"Tommy . . ." Billy sounded horrified and tried to put a hand on Tommy's shoulder again.

And again, Tommy shrugged him off. "Don't touch me, damn it."

Magneto regarded his grandson for a moment, feeling emotions swell inside of him. Anger and rage were predominant at the moment, but were quickly giving way to sorrow and regret . . . and empathy.

"You have nothing to be ashamed of, Thomas," he said.

"Easy for you to say," muttered Tommy, glaring at the floor and not meeting anyone's eyes.

Magneto began rolling up his sleeve until his own tattoo was visible. His own identification numbers, from his time in the Nazi camp. "It is not easy to say, Tommy . . . and it took a very long time for me to be able to believe it. But that does not make it any less true." He clamped his free hand down on Tommy's shoulder, prepared to hang on if Tommy attempted to shrug him off like he had his brother. But Tommy didn't. Perhaps because it was his grandfather. Or perhaps because, for the first time ever, Magneto had called him Tommy rather than Thomas. Whatever the reason, Tommy had raised his eyes and locked them onto Magneto's tattoo. A noise of surprise caught in the back of his throat.

Magneto held his arm still until he knew that Tommy had gotten a good long look, then clamped his hand down on Tommy's other shoulder.

"You have nothing to be ashamed of," Magneto said again. "You did not deserve what happened to you and it was not your fault."

Tommy raised his shoulders slightly, shrugging in response to Magneto's remark, but not trying to shrug him off. "I know."

"It was not your fault, Thomas."

Tommy looked up to meet his eyes with a little bit of confusion. "I know . . ." he said, uncertainly.

"It was not your fault."

Tommy's shoulders began to shake and his eyes grew glassy. He broke off eye contact and looked to one side, only to find Billy standing right beside him, watching him with concern. When he averted his gaze to the other side, it was to find Hawkeye watching with that same concern, so he moved his gaze to the floor instead.

"It was not your fault, child."

Tommy gave a dry sob and quickly rubbed the back of one hand over his eyes, trying to stem his tears. His shoulders started shaking harder then he slumped forward so that his forehead was rested against Magneto's chest. He would have fallen completely had Magneto not held him up.

"I'm n-n-not crying," Tommy said defiantly, though anyone could tell just by his tone that his words were a lie. "I'm n-n-not."

"Hush, child. You have nothing to prove to anyone."

Magneto gave Billy an approving nod when he wrapped his arms around his brother , giving him a sideways hug. Hawkeye and Hulkling hung close but both seemed hesitant to touch him, like they were afraid they might spook him.

It took Tommy a few minutes to get himself under control again. That was good, in Magneto's opinion. He needed to let it all out. If he didn't, it would poison his life for years to come, just as Magneto had let his own life be poisoned . . . though the actions Magneto had subsequently taken weren't anywhere close to being his greatest regret.

"M-Magneto?" Tommy finally asked once he was all cried out.

"Yes, child?"

"I'm sorry for what happened to you." Tommy's voice cracked and he looked up at Magneto with sympathetic eyes. "You didn't deserve it either."

Magneto rested a hand on Tommy's white hair, unable to help marveling at the boy's strength. Where Magneto had only had hate and a thirst for revenge after the horrors he faced, Tommy had found empathy.

"I'm the one who's sorry, Thomas," Magneto told him. "I should have stopped this from ever happening to you."

Tommy shook his head. "You didn't know. And there was nothing you could have done."

But that wasn't true. Magneto hadn't known, but everything he'd ever done had been to try to stop any other mutants from ever experiencing what Magneto himself had. He'd wanted to make a world where no child would ever be locked up and experimented on because they had powers. He'd wanted to make the world a safe place for his children, and their children.

But he'd failed, and his grandson had paid the price.

And that, more than any of his other failures or mistakes, would weigh heavily on Magneto for the rest of his life.