The Horcrux

Grindelwald was considerably more gray haired than his light side counterpart of the same age (Harry had to admit seeing color in Dumbledore's hair had been nothing short of bizarre for him, but he'd been a little more focused on not getting his eyes pecked out at the time), but not less intimidating for it.

"Perhaps if you make yourself useful and surrender all your secrets unto us, we'll let you live," Riddle said a little too cockily. "I would like to know what you know of soul magic, in particular." Maybe wait until they'd actually beaten him, Riddle? But then, he'd always been like this, hadn't he?

"My lord, no matter what we throw at them, they don't seem to die. That one took a curse that should have split him in half!" a witch jabbed her wand in Harry's direction, and he gave a grim smile. "He's not an Inferus, he's something else, mi'lord, something very dark and dangerous. The other one appears to be a student but they move in sync like they've been fighting together for a very long time."

Grindelwald surveyed him, and made a slight wave of the elder wand in some sort of detection spell. Harry was ready to dodge, but the dark magic merely brushed up against his own, and Grindelwald hissed, "Horcrux." Harry immediately stiffened, and Riddle was fascinated. How did Grindelwald know? And damn it, this meant Riddle had learned the word early - or, if they were stuck in a time loop (something Hermione acknowledged as a possibility if things went wrong), maybe he'd just provided the damn inspiration for Riddle to go and track down what it meant from Slughorn! He hated time travel. Unfortunately, they really had no other choice, and there was no going back now on what he'd done. "Or something very like it. What madman would make a living horcrux?" Grindelwald moved slowly, circling around them and not yet attacking, speaking more to himself and to his followers than to them. "But if one was a horcrux of the other, that would explain it. My people!" He pitched his voice wider. "You must utilize fiend-fyre! Only it or stronger magics will do against such a foe utilizing the darkest of magics!"

Shit. That should actually work, shouldn't it?

He couldn't believe it hadn't occurred to him earlier, actually, and could only blame the discombobulation of the hectic past few days. If he was now a full blown horcrux, instead of the more vulnerable improper one he'd used to be, then nothing less than very strong magics would be enough to destroy him, such as basilisk venom coated on Gryffindor's sword*, not that any of his foes here would have anything like that, most likely. But fiendfyre? That they could definitely do.

Actually, maybe he should just let them. He felt someone throwing a selective anti-apparation ward up like the one they'd managed before on Diagon Alley, and he knew Tom wouldn't survive here without him. Harry stood still as the group of wizards began to cast. How much did he really deserve to live, anyway?

Immediately, he felt Tom's rage and indignation. "Now is not the time for your suicidal tendencies!" the younger man shouted, shoving into him and forcing him away from the first round of fire. Abruptly, the urge to preserve his own life became far more intense, as well as the pain from his wounds, although those started to fade as Tom started to heal him. "You said you'd show me things? So keep your bloody promise!"

Right, right. He supposed he could do that. Harry forced more statues of earth to life to dance in front of them as shields, created a wall of water (not that this was a good long term solution, but it made a temporary barrier for a second or two), then sent out his own flame to add to the inferno. His hope of wresting control of the entire thing was zero, but he could make it more chaotic and use the existing flame to provide cover for which direction his own might be traveling, and Harry managed to boil a trio of wizards to death that way.

But he had to reluctantly admit, Grindelwald was more skilled: having others disappear he simply took hold of their flames himself like a master.

He could also feel Tom's fear and anxiety spike. It was one thing to agree to a fight when you thought nothing could kill you, it was another when you realized that not only did your opponent know your weaknesses better than you did, but he was stronger and more skillful than you too and had shown zero interest in bargaining with you.

The growing flames reminded him of something else, however, which was a little more urgent. The freed prisoners! As many had apparently been Muggles, they hadn't managed to get far away yet without assistance and now were in danger of being devoured by the flames as they grew nearer. Children screamed. Harry cursed - while Riddle threw out curses without pause, but seemed to note Harry's distraction and made an exasperated noise. "Keep him from killing us all and I'll try to take the wards down, then start apparating them out." Ward breaking was a specialized profession that a 16 year old should have had no chance at, but Riddle was no average 16 year old.

Moving close to his side to better protect him, Harry said quietly, just loudly enough to be heard over the crackle of flame but not so much he had to worry about distant enemies hearing them: "I'm surprised you care."

"I don't," Riddle said bitterly. "But you do and I can feel that you do. Is that good enough for you, or do you want to wait for someone more noble to show up?"

Harry supposed considering the situation it would have to do. And one couldn't expect miracle personality changes over-night. "Thank you."

To- Marvolo seemed a little perplexed at his genuine gratitude, but didn't actively dislike it. The boy turned his attention to the wards, keeping just half an eye on Harry in case he decided to do something ridiculously suicidal again and couldn't be trusted to actually watch his back.

It was at this point that Grindelwald switched strategies, taking advantage of the selective wards and apparating behind them or to the sides and firing off spells while letting the fiendfyre grow wild and loose so that Harry would have multiple problems to deal with, even though most of his minions had fled already and it was just Grindelwald now, this had if anything made the fight harder because now Grindelwald didn't have to bother with controlling the flame to make sure it didn't eat anyone he actually wanted to keep alive on his side.

Then Grindelwald began to cast a spell Harry didn't recognize but looked an awful lot like a shield, and instead of trying to hit them with it steadily grew it around them like a bubble. Harry didn't need to guess what it did on completion to guess that this was a not a great thing to let Grindelwald just do, and he fired an Avada Kedavra to force the man to move and break concentration. Instead of dodging, the man held up another wand in his other hand, gave a twist, and a mirror took the blow, shattering into a thousand pieces.

Dual casting from both hands? Shit. He'd literately never seen that before, but didn't need to to know it was damn useful. Just how accomplished was this wizard? How had Dumbledore ever defeated him? He hated to say it, but Grindelwald might actually be a tougher opponent than Voldemort, except for the whole 'mortal' thing. That might be their only advantage.

Now the bubble had completely surrounded them. The good news is that the flames suddenly got a lot duller.

The bad news is that it was almost certainly cutting them off from all fresh air. And daggers started to materialize all along the bubble.

fuck.

"I've got the wards!" Marvolo said excitedly, and in that moment, several things happened.

The daggers fired toward them from all directions. A phoenix popped out of the air in a glorious blaze of light, and a wand flick arrested the thousand blades headed toward their direction, done by the free hand of a familiar red-headed man holding on to the phoenix.

"Grindelwald! Our non-interference agreement held that you would not attack one of my students!"

"They attacked me and my men first, Albus. Or are we no longer on first name terms, hm? But very well. Take them and make sure they do not get in my way again, and I will not attempt to detain anyone here. Although I truly wonder if you truly want the older one; he's as dark as they come. Mark my words, Albus, you should get rid of him before he causes harm even I wouldn't dream of." Now that was just unfair - but Harry was a little too shocked to be indignant about it.

Albus Dumbledore had arrived, and he gave them a look that told them they were in very deep trouble.

"Sir," Riddle said a little uneasily. It was interesting to be able to feel what was an act and what wasn't. Marvolo was definitely anxious. He was not, however, feeling particularly genuinely respectful. "I can explain-"

Dumbledore grabbed their hands and they collectively vanished, reappearing in the cobble-stoned halls of a familiar school. Then the old man turned, barely restraining his phoenix from making a go at Harry again with his hands.

"What were you thinking?" he barked with uncharacteristic rage. "A young man not even out of school, trying to take on one of the most powerful wizards in the entire world and many times your age?" Ironically, this made Harry go from being cowed to wanting to laugh. Really? Albus was lecturing Harry on not facing dark wizards many times his age and skill? Really? Of course the man didn't know the future, but it still felt so hypocritical. "Do you have any idea how easily you could have died? How close you were to doing so before I arrived, alerted by a frantic auror that two students under his watch had gone missing and were from reports apparently chasing the war front?"

Marvolo, of course, did not understand or know the source of his amusement, and just shifted in confusion at the feeling he'd gotten from him at his side, although he agreed with the feeling of disdain that accompanied it.

"Sir, we weren't really trying to go after Grindelwald," Marvolo lied. "We rescued people-"

"And that is very noble of you, if that was indeed your plan," Dumbledore stated with none of his firmness lost; one could tell he didn't really believe Riddle. "But you still should not have done what you did. You are not aurors, you are students." Finally, he looked at Harry, like he was some sort of dirt under his shoe. It was both hilarious and rather sad: he hadn't thought at this time that Dumbledore could possibly dislike any student more than Riddle, but apparently Harry had managed to 'win' that contest without even trying. All because he was drenched in dark magic. Which, to be fair, would have made Harry himself uneasy about a person only a few months ago, but he'd learned the hard way beggars couldn't always be choosers about allies, so it wouldn't completely stop him from giving them a chance if they made themselves useful enough. War that you had to fight, instead of hiding behind walls while others died at the hands of your 'friend', had a way of making you pragmatic - sometimes, you had to use what tools were available even if it stained your hands permanently. "You. This is not the sort of reckless behavior Mr. Riddle normally engages in. I assume this was your doing?" Stealing, tormenting, that sort of reckless yes, running off to fight wars almost solo with only one person for backup, no, was the hidden statement.

"I can't take all the credit," Harry huffed. "Marv isn't exactly a mindless minion."

Marvolo stiffened. "Did you just call me 'Marv'?" he hissed.

"Oh, come on, Marvolo is awkward and stiff," Harry complained. "I keep accidentally calling you Tom in my head all the time, and I know you hate that worse. Or, hm, how about Marvo?" He brushed a hand against Marv's to allow a silent communication between them, 'besides, I think if you met the real Marvolo you would not be too keen to share the same sound with them. This differentiates you a bit but still gives you something more serious to put in writing, right Marvo?'

Marv gave an agitated twitch, and Dumbledore looked faintly amused, his anger finally fading slightly, though not gone. "Be as it may, I will have to assign the both of you detention when you finally start term."

"What?" Marv gasped, doubtlessly thinking of his near-perfect record and image as a student. "But we were being heroic like one of your brainless Gryffindors! I thought this was what you always wanted me to do? This is a horrible double standard!"

Albus sighed. "No, it is not, Tom," Didn't Dumbledore just overhear the conversation between them about how much Marvo hated being called Tom? Well, then again, he called him Tom after he started going by Voldemort, it just... somehow hadn't seemed so petty and dickish at the time, probably because they were talking about a mass murderer and not a teenager with family issues.**

Hm. Which sounded better? Marvo, Marv, Marvo, Marv...

Would you shut up? came a thought that wasn't his own. Oh yeah, he was still brushing his hand against his, wasn't he?

If it makes you feel better, I don't have any murderous feelings associated with those names.

That made Riddle awfully quiet, before jerking his hand away, but there was one confused thought he caught half of first. Why would he have murderous feelings associated with-

Harry needed to be more careful or he was going to give everything away. Lying really wasn't his strong point.

"As it is, I suppose there is nothing left to do for now but to give you accommodations here at Hogwarts, since you clearly cannot be trusted unsupervised anywhere else." Here, both Harry and Marv exchanged looks of delighted surprise.

This was a big difference. If Harry knew one thing, it was that Tom Marvolo Riddle had not been allowed to stay during any summer at Hogwarts, despite begging for his life as bombs rained. That meant, however small, Harry Evans had officially just changed history.

"Of course, considering term is about to start, you won't be enjoying this for very long," Dumbledore said wryly. "And since you are already here, you may as well get started on those detentions. Scrubbing, without wands."

Harry groaned. Marv-o was too dignified to, but Harry could tell he wanted to. 'Lighten up,' he told him with a quick smack. Marv gave him an annoyed quick smack back in the shoulder, before remembering Dumbledore was watching and growing embarrassed, since it looked like they were roughhousing for no reason (or perhaps from silently blaming the other for their misfortune) and that was beneath his dignity, apparently.

Dumbledore looked torn between amusement at Riddle acting the most human he'd ever really seen him and wariness that this was all some strange new act concocted by the both of them, with a great deal of it centered on Harry.

"I hope Mr. Evans will not prove to be a disruptive influence on you, my dear boy." Riddle was hardly his 'dear anything'. And why was Harry the one getting blamed for this as the 'disruptive influence'?! C'mon, Dumbledore even knew what a bastard Riddle was! This was just totally unfair.

Riddle was silently laughing at him, he could just feel it. Literately, feel it.

Then Dumbledore presented them both with a bucket and two mops, and his humor vanished into the abyss of indignant rage.

Marvvvvv, it sucks to be you.

Not long after Dumbledore was gone, moving off to prevent Fawkes from committing a gruesome murder by pecking Harry to death (not that Harry was sure that would really work, but phoenixes did have some really powerful magic, maybe it could burn him?), the two of them started roughhousing for real, Harry irritating Tom (sorry not sorry, damn it, it really was hard to break old habits!) into starting it and then Harry definitely determined to finish it - at which point it was abruptly clear dear Marv was used to relying on his magic for everything and did not in fact know how to wrestle, whereas Harry had very quickly learned how such things worked in the house of Dursley: you squirm like the dickens out of any holds and if you have it, use your superior weight and muscle. Harry might not be the largest from his malnourished years, but To- Riddle was both younger and softer than him, clearly not used to hard physical labor the way Harry was. So Harry had the clear advantage, but Riddle had sheer spite driving every fiber of his being and that could not be discounted.

They ended up sloshing a lot of water everywhere and kicking the bucket over and having to refill it.

It was stupid, but it was also... kind of the first fun he'd had in a really long time, the close contact making him feel a lot less empty and the pestering reminding him of Ron or the twins. And because his mood was infectious, he knew Marv didn't have a completely terrible time, either, even if he was making a face every time Harry thought that nickname, and even if the merriment was causing him a lot of confusion. He really got the feeling Riddle had never done this before and was a little flustered at how undignified it was, and he got practically murderous when Harry tried to tickle him. OK, got it, no tickling, Merlin! Who knew one person could be so touchy?

"If you behave like that in front of other students I will kill you," Riddle warned him, trying and failing to give off a feeling of deadly seriousness when Harry's own fit of near-giggles was effecting him.

"Wouldn't dream of it, Marvo," Harry said with a mischievous grin.

"Ugh," said Marv.

"You still haven't said which of those you prefer. Marv or Marvo?"

"How about Voldemort?"

"No deal," Harry said flatly. "Not unless you want me to start thinking about murdering you again." He'd literately only just stopped, but if 'dear boy' Voldemort really was that eager...

"Fine," Marv said, exasperated. "Either, just pick one and be consistent about it if you insist on this. Marv sounds more like a real name but it also sounds like it's short for 'Marvin'," he said with faint distaste. "Marvo is closer to my actual name, so maybe you'll actually remember it, eventually, if you aren't a complete dunderhead. I couldn't help but notice how you keep accidentally switching to thinking of me as Tom, though you try to correct yourself. Is Marvolo really so many syllables you must shorten it to remember?"

Harry mock-gasped. "Marv, was that a compliment? Me, not a complete dunderhead?"

"Of course not. Your ego must be quite sad if you are willing to accept that as a compliment, but then," Marvolo added slyly, "I already knew you had non-existent self esteem from the way you keep trying to off yourself or refuse to take care of yourself in any way. Speaking of, how are your wounds?"

"You did a good job," he complimented, capable of giving one even if Marv wasn't. "Y'know, it's kinda funny that either Dumbledore was so pissed at us he forgot to check if we needed to go the wing, or he unconsciously trusted our abilities enough he didn't think he needed to."

Marv's lips quirked, most likely from the enjoyment of having his abilities accidentally acknowledged by a 'foe'. "That is a little funny. Your sense of humor is not completely demented, then."

"Ah, please." Harry scoffed. "All of it is demented. I'm just a terrible influence and I'm corrupting you, remember?"

Now T. Marvolo Riddle really did give a small groan. Though some of that might have been from all his new bruises. Then, he grew serious, and asked a question he'd been dreading:

"Harry. What exactly is a horcrux?"

Voldemort- well, alright, maybe for the sake of self preservation when around someone who occasionally could read his mind, he'd think of himself as Marvolo for now (And definitely not 'Marvo' damn him, that sounded ridiculous) - could tell Harry very much did not want to answer.

"Maybe I'll tell you later," Harry hedged, indecisive. It was funny (well, not really) how he could be so firm and powerful one moment, cold and monstrous, and then seem like such a weak fool and clown the next. How he could both so fearlessly go after Grindelwald, survive, but also nearly get them both killed doing the same thing because he didn't plan things out enough before charging in.

Although, depending on what a horcrux was, maybe it was not entirely his fault, if he hadn't known or realized the weakness. Still, since he had clearly been keeping things secret and had some recognition of what it was, it was his fault for not telling Marvolo sooner so he could identify it as a possibility for him, as he was sure he would have. He was the most brilliant student of his generation after all, no one matched Lord Vol-

ahem, Marvolo.

"I want to know now. It clearly has to do with our bond, and if you don't tell me, I'll track down the information for myself," he threatened.

Harry sighed. "I know you will." That was... surprising. Did Harry really have such confidence in his abilities (as he should!), or was that his seer-nature coming through? The more he knew about him, the more it fit. Being a seer was the only possible way Harry could have already developed a hatred for the 'Lord Voldemort' name, even when one took mind-reading into account that just didn't explain the sheer vehemence. "I suppose it won't actually help you figure out our situation that much. A horcrux is a soul fragment."

A soul fragment. One could shred souls? Marvolo was riveted. If this meant what he thought it did then... "You could split yourself and attain immortality," he almost salivated over it, except, of course, such was below his dignity. "But you couldn't possibly be my soul fragment. I would remember if I had attempted such a ritual," Riddle stated with a frown. It was genuinely perplexing and didn't make much sense. "Were you attempting such a ritual on me and botched it up?" It was the only thing that made sense, except in that case, Riddle should be Harry's horcrux, not the other way around... but maybe in this situation it didn't matter, or he had somehow messed up so bad they were both each other's horcrux?

Harry hesitated again.

"Don't lie to me," Marvolo demanded, annoyed that the other boy had the gall to be so transparent about it. Honestly, he could have sworn he was more effective at lying when he first met him... now wasn't that a strange thought? At least he didn't remember him being quite so sheepish.

"No, I wasn't attempting it on you. But I did meddle with dark soul magic right before I met you," Harry admitted. "Which is certainly the cause of our predicament, and why Grindelwald thought I was a horcrux. Resistance to most magics was a known possible side-effect of the ritual I was a part of."

"Which you will not be teaching me, I take it," Marvolo stated.

Harry shook his head. "No. But like I said, I'm sure you'll eventually figure out the same magics. You don't really need me to do it."

Morgana, Harry was so frustrating. But he was so knowledgeable and powerful, Marvolo couldn't help but crave the thought of what could happen if he could actually get Harry to do his bidding, to eat out of his palm. The problem was, what motivated him? He had very little self preservation or self-esteem, so appeal to ego was out. He liked going after Grindelwald and enjoyed a good challenge, that was something, at least. And Harry wanted Marvolo to feign... empathy, or something, though heavens knew why. If he knew exactly what he got out of it, maybe he could coax him to something more worthy of someone of his power. The weak didn't deserve protecting. If he had to empathize, why not with the strong? Maybe it was the admiration of the weak he wanted. He could understand that, but there were other ways of getting it, or at least, one should demand the weak offer proper obeisance first. Someone who was willing to meddle in dark magic couldn't be as big a fool as Dumbledore, and Dumbledore had already hideously mis-stepped in automatically treating him as an enemy, potentially pushing him closer to Marvolo's side instead of the light. He even admitted muggles could be a threat, so he wasn't a total lover of them. There were threads he could work with here, he just had to figure out how to twist them, weave them to his purposes, in such a way that even a seer would have trouble evading his traps. He couldn't possibly evade everything, especially if the trap was verbal, could he?

"You can count on it," Riddle promised darkly, but his mind was already on something else that he was determined to do.

He was going to unravel Harry Evans and make him useful or make him gone.

And if he could figure out immortality without him, as Evans assured he could, well... while having two sources of immortality was better than one, if he couldn't overpower Evans and get him properly under heel, it would probably be better to just make him gone.

A/N:

**Everyone and their brother probably knows at this point about Rowling being a giant shitweasel to trans people, so in hindsight, the 'people have to keep their birth names forever' thing should have been a red-flag. Also, I will neeeever, ever forget how she said wizards used to just shit themselves where they stood and vanish it before plumbing was invented. What the hell, Rowling? You are really sending your reputation down the... vanishing charm. Considering part of her own books have Harry and Ron in a girl's bathroom not once but multiple times, I do have to wonder if she was always this transphobic or if this is new, though, or if this is 'it is okay if someone I likes does it but not someone I dislike' syndrome. (Suffice to say, the vanishing charm thing isn't going to be treated as canon here, like rofl.)

Anyway, it's really hard to break old habits and even I use the wrong name for him, hence why Harry keeps doing it too. Nothing to be ashamed of there, just acknowledge your screw-ups and move on.

*So this was hard to write and hopefully I didn't screw it up (Did Nagini require Gryffindor's sword dipped in basilisk venom or would any sword have done the job? I can't remember) since it's been some years since I read the books; I recalled horcruxes could only be destroyed in certain ways, yet Harry as one of them didn't seem to count or we wouldn't have needed to be so worried about him every time he had a scrape with death, now would we? So my explanation here is that he was an improper horcrux before, and now he's more like a proper one with a variety of protections laid on him by Hermione, who of course being willing to sacrifice everything doesn't care any longer just how dark she makes the magic around him if it'll keep him alive. If what he has right now can truly be called life, of course. So, Harry is a little OP, but fiend-fyre and basilisk venom is still able to destroy/kill his body; I tried to keep it relatively canon here and not just him being strong for the sake of being strong.

The rough-housing scene was unplanned, but Riddle doesn't strike me as the sort of person to take being smacked without retaliation, even if he's currently expected to do no magic and a little too exhausted for wandless casting, so I don't think Harry would have too much trouble provoking him into it. And we know from Harry's many pithy comments in the series, such as suggesting that a toilet might be sick if Dudley was introduced to it, that he's not actually devoid of a sense of humor. Young men tend to rough-house, and Ron seems pretty stereotypical, so I imagine he and Harry would on occasion, and it sort of just developed spontaneously here. Friendly touching is, like I've written before, really important to proper psychological development and healing if one didn't receive it as a child, so this is a (tiny) step forward. Of course, next time they'll probably just hex each other when they get their wands back...

For Harry's mental health, he's feeling a bit better and acting more like his old self due to proximity with the rest of 'his' soul, which, naturally, Riddle hates with a passion. No jokes at his expense allowed, dammit! Being proactive again helped too. Harry is the sort who likes rescuing people, so it boosts his morale.

Science Notes: Lastly, for those interested, I read about a new study that found psychopaths can experience regret (in terms of things like gambling), they're just really bad at actually acting on what they learn from it because of malformed decision making skills. Pretty much meshes with all the other articles out there.

Also interesting are 'Machiavellian personality types', individuals who aren't necessarily psychopathic but are pretty awful in their own right; it isn't a mental disorder, those individuals are terrifyingly sane. If things work out, Tom will probably graduate to 'merely' being fairly Machiavellian instead of pure psychopath. Which could end up making him worse to deal with, really; if he decides to go after you, who would you rather have, the impulsive version or the one who can properly respond to past mistakes and plot long-term and resist torturing his followers so they have more incentive to be actually loyal to him?