A/N: This was written as prompt for the Downworlders Network Battles on tumblr (the prompt was crossover, Shadowhunter Chronicles and another fandom) and it totally ran away with me oops. I didn't mean for it to be so long, and this is only part one, which is really just introducing the characters omg. I reckon it will have about three parts but idk yet

This is a Mortal Instruments and Fullmetal Alchemist crossover, but I reckon it can be read without knowledge of fma tbh, as it's set in the tmi universe and I've changed and explained all the characters and things that I've brought in from fma
(it contains royed too oh god i'm such trash)


It all started when two strange boys showed up at the Institute.

Things had been settled since they had returned from Idris after defeating Sebastian, and for once shadowhunting duties had been going about as normal. Isabelle had been having a hard time adjusting to this new Simon, a Simon who was still trying to piece together the Shadow World and his role in it, but she was trying as well to accept him as he was now, and not lingering on the past, because there was nothing she could do about it now. Alec had finally packed up his things and moved in with Magnus, but he was still at the Institute virtually every day. But things had finally settled into something of a routine, something normal, or normal enough for the shadowhunters of New York.

But then one day, two strangers tumbled out of the elevator, bloody and bruised. They were both blond, and had similar facial features, which led Isabelle to immediately think that they were brothers. The taller one was carrying the shorter one in his arms since he was unconscious, his breathing shallow. There was a nasty cut on his left shoulder, blood oozing out lazily yet fatally. There was a stench in the air, something familiar and awful, reminding her of one of the worst days of her life: the day Alec had been poisoned. The short boy with the long hair tied back in a braid had been poisoned by a demon, and a powerful one by the looks of him. He was fading quickly, his skin pale and dull as he hung limply in his brothers arms.

At first she was so shocked to see these two seemingly mundane strangers having found their way into the Institute with wounds as serious as demon poisoning. They had no obvious runes on them that she could see so she doubted they were Shadowhunters, and they had no obvious markings of a Downworlder, though she wouldn't rule out the possibility. But all she could do was stand and gape as the short haired boy hauled his brother into the corridor, trailing a deep red colour along the floor.

She wasn't sure what to do until she saw the boy's eyes. They were a rich golden colour, reminding her of Jace, but they were wide and frantic. They conveyed the utter panic and terror that the boy was feeling at that moment; he was petrified for his brother's life. He could see his brother's life bleeding out in front of him, knew that the poison was consuming him slowly, and he was petrified.

Isabelle knew that look, knew it well, because she had worn it that day, that day when Alec had been poisoned by Abbadon and she had thought that he was going to die.

"Please," the boy whispered. His voice was small, but confident still. It was not an American accent, British if anything, though there was something else mixed in there too. "Please, help him. Help us."

Without a word, Isabelle was helping him, picking up the smaller boy and then they were carrying him, and she was leading them towards the infirmary. She knew that was perhaps being a bit too spontaneous, that she should question them first and see who, and what, they were, but that would take too long. This boy needed help now, and after seeing the raw love and care his brother had for him, no matter who they turned out to be, Isabelle knew that she was going to help them. She was not going to let this boy die, and she certainly was not going to let his brother be devastated. She simply would not allow it, not with thoughts of her and Alec being in that position racing through her mind.

"Who are you? And what happened here?" Depending on how powerful the demon was, she knew that she might have to call for more help, probably from Magnus. Especially if she could not rune them, because she had very rarely had to treat mundanes or Downworlders before.

They were nearly at the infirmary when he answered. "I'm Alphonse Elric, and this is my older brother, Edward." He looked at her apprehensively, as if unsure whether to trust her, then down at his brother, before carrying on. "We're Shadowhunters," he seemed to blurt, flashing his voyance rune on his right hand in front of Isabelle's face. She frowned as she realised that the permanent rune given to all shadowhunters seemed to be the only one on his body. She realised something else: she'd thought that he was British before, but now she realised that his accent was unmistakeably from Idris.

Confused as she was, she wasn't going to start questioning it now. There were more important things to be worrying about. They reached the infirmary and laid Edward down on a bed just as Alphonse said, "We were attacked by a group of Moloch demons—"

Isabelle cut him off. "Moloch demons couldn't do something like this. Unless…unless you faced their leader."

Alphonse looked down at his brother on the bed. "I don't know for sure. And I don't care much. All I know is that he's hurt, that he's been poisoned. I didn't know what to do; I drew a couple of iratzes, but they didn't do much. And we've only just arrived in New York really, we still don't know many people here, so I panicked and then we ended up here."

Isabelle could only nod as she looked down to examine Edward. The entire sleeve of the left arm of his jacket had been shredded and ripped, and the wound on his shoulder was deep. She could see the hastily drawn iratzes that Alphonse had mentioned, but they were already fading.

"Shit," she muttered under her breath. "This is really bad. I'm going to have to call Magnus, there's not much that I can do with just runes."

"Magnus? As in Magnus Bane, the High Warlock of Brooklyn?"

Under any other circumstance, she would have grinned at him, but that didn't really seem appropriate. "The one and only. Look, I'm going to go and call him, I'll tell him it's urgent and that he better haul his ass here like immediately. And then I'm going to find Clary, I think she's in the training room with Jace, and see if she has any runes that will help. I'll be five minutes tops, but you should stay here with him."

Alphonse nodded, albeit looking a bit confused, and she brought out her phone as she started to walk out of the room.

"Wait!" he called out after her. She turned around to look at him, his molten gold eyes piercing her. "I don't even know your name."

This time she did flash him a grin, even though it was small and short. "It's Isabelle. Isabelle Lightwood."


Isabelle returned, true to her word, exactly five minutes later. She had a short red-haired girl in tow, with bright green eyes and a smattering of freckles across her face. This must be Clary, who Isabelle had mentioned before. And behind her, there was a tall blond boy, who Al could only assume to be Jace. His eyes were a striking golden colour, and Al held his breath as he wondered what that could mean. With such distinctive eyes, the same eyes as his and Ed's, there had to be some story behind them.

"Magnus is on his way," said Isabelle, her dark eyes steady and her voice unwavering. She had been so amazing and so kind; just thinking about it made his heart swell.

But he knew that it was far from over. Because Ed was still lying on the bed, his eyes still closed and his breathing shallow.

Clary took her stele out, and leant over Ed, drawing swirling runes near his gaping wound. Some of them were runes that he didn't recognise, which confused Al as eh had studied virtually all of the runes in the Grey Book when he was younger. He couldn't bring himself to question it too much, because all he could think of was Ed, and how he couldn't possibly die. He couldn't because he was Ed, he was his big brother who had always been there to protect him, who would walk to the ends of the Earth just to make sure that Al was safe. Ed's presence always filled a room, and even when their life had turned to shit, he could always make Al smile. Al couldn't even bear the possibility of losing him.

But Clary's runes did seem to be doing something, as Al was fairly certain that Ed wasn't bleeding as horrifically as before.

And then the doors to Institute opened once more, and two more people stepped in. The man in the front was wearing a long black thing that resembled a cloak and ripped skinny jeans, along with an extremely high quantity of glitter. His skin was caramel coloured, and he was probably from somewhere in far-east Asia. His eyes were the most unusual feature of his face: they were green gold and with slit pupils like a cat's. An unmistakeable warlock mark. This must be Magnus Bane.

Behind him was someone who was even taller than Magnus, with pale skin and dark hair. His stand out feature was definitely his eyes, which were like blue lamps shining from his face. He was wearing a more sombre outfit of an unremarkable grey sweater and jeans. He looked quite a lot like Isabelle, and Al decided that they were probably siblings. He wondered absently if they were as close and him and Ed.

"Magnus, thank God," Isabelle sighed, and the genuineness behind her voice struck him yet again. They were all being so incredibly helpful, and Al was a bit overwhelmed by their kindness. They didn't know him or Ed, and yet they all seemed to care about whether Ed lived or not. Those kinds of people were the best sort.

Magnus looked at him briefly, their eyes meeting in a flash. His cat eyes were unnerving, but Al didn't dare look away. It was Magnus who broke his gaze, proceeding to look down at Ed. His eyes narrowed.

"Everyone get out," Magnus demanded, his voice cool and collected. "This is going to take a while, and it won't help to have all of you here distracting me."

He didn't want to leave, and getting up and moving away from Ed was real struggle. It was so hard, knowing that he was leaving Ed's life in the hands of a complete stranger. He knew that he had no choice, but it was difficult nevertheless.

He followed the rest of the gathered teenagers out of the room, leaving his brother's fate completely and totally with Magnus.

He couldn't help but wince as the door shut behind him.


The waiting was utterly unbearable, and the tension in the air was making Al cringe.

The four of them had convened in the library, which was a huge room filled to the brim with books. Despite the circumstances, Al couldn't help but admire the overflowing shelves, and the smell of old books that hung in the air. It had been a long time since he'd been in an Institute library, so he'd almost forgotten how beautiful seeing all these books in one space was.

Clary and Jace had introduced themselves to him properly, and the other boy who had come in with Magnus had introduced himself as Alec Lightwood. He was right with his assumption that he was Isabelle's brother.

He'd told them all his and Ed's names and not much else; he was far too tired and worried to even begin to explain anything to them, though he did notice Isabelle looking at his lack of runes sceptically.

After a moment's silence, Alec spoke again, his voice quiet and tentative. "I was poisoned by a demon once. A Greater Demon, Abbadon. And Magnus was the one who healed me. Your brother is in good hands, Alphonse."

Al didn't really know how to respond, other than nodding. "Thank you," he murmured, looking down. Knowing that Alec was living, breathing proof that Ed had a chance comforted him, and made him feel a little bit lighter.

The thought hit him like a tonne of bricks after another few minutes of awkward silence.

"Shit," Al cursed, the violence of it surprising even himself. He was not usually one to swear: he had Ed for all that, but the word tumbled out of his lips anyway. "Shit, I need to call Roy."

He had four pairs of curious eyes on him, but he barely noticed. He was already taking out his mobile and finding Roy's number, his legs taking him out of the room and out of earshot of the other shadowhunters.

Thankfully, none of them followed him. He hit call as he found an empty room and waited with his breath held for Roy to answer. Phones didn't work in Alicante, but Roy lived just outside the glass city, and Al could only hope that he would be at his house. He didn't think he'd ever actually called Roy before, though he had heard him and Ed on the phone many times.

There were a few rings, during which Al's heart pounded in his chest, before Roy picked up.

"Ed, I do hope you realise it's two in the morning here." Roy's voice was deep and teasing, and Al got the feeling that Roy wouldn't actually mind if Ed woke him up just to talk. He also wasn't surprised that he assumed that it was Ed calling, but Roy's obliviousness made his chest hurt a little.

"Roy, it's Alphonse. I'm sorry for waking you, but it's an emergency. Brother's been hurt, we were attacked by a group of demons, and I think we may have faced a Greater Demon, I'm not really sure but it was going for me and then all of a sudden Ed was in front of me and he got hurt really bad. Demon poisoning. I panicked so I brought him to the New York Institute, but he was unconscious and bleeding everywhere and now he's in the infirmary with a warlock who's apparently healing him but—"

He was rambling and he was aware of it, but all the anxiety and worry and guilt he'd been feeling seemed to spill out. Talking to Roy wasn't like talking to the strangers of the Institute, nice as they were. Roy was someone who Al had known since he was eleven, someone who he'd admired growing up, and someone who cared about Ed completely. Someone, the only person really, who might love Ed as much as Al did.

"Fuck," Roy spat, and Al could hear ruffling sounds and crashes from the other end of the phone. He could envision Roy getting out of bed, his dark hair sticking up and his eyes wild. He could hear the worry and concern he had for Ed, even in that one curse. "Fuck, Al, he's gonna be alright. I'm gonna find someone who'll make me a portal or something, and I'm gonna get there as soon as I fucking can, okay? And if he wakes up before I get there, you tell him that I'm coming."

Al nodded, then stupidly realised that Roy couldn't see him, so quickly rectified it by saying, "Of course. I was so scared, Roy. That he was going to—"

"Stop there, Al, you know it won't do any good. He'll be fine, he's Edward fucking Elric, he's been through worse shit than this and you know it. I'll be there as soon as I can."

He was right, and Al knew he was right. Ed would be fine, he had to be. "Okay." It came out as barely more than a whisper. There were tears on his cheeks, and he didn't even know when they'd leaked out. Had it been during his conversation with Roy, or before? "Okay, we'll see you soon."

With that, he hung up.


When Alphonse came back into the library, his golden eyes were red and puffy, as if he had been crying a little. Clary couldn't help but feel for him. His brother had very nearly died, and his life was totally in the hands of a complete stranger, she would be surprised if he didn't shed a tear or two.

After Alphonse had found a seat, Clary was about to open her mouth and ask if he was alright, but Jace got there before her.

"So, who's Roy?" Sometimes her boyfriend was really dense when it came to things like this. Alphonse looked more like he needed a hug than prying questions.

"Jace," she scolded, whacking his arm lightly. "Stop being so nosy."

He shot her a look that seemed to say, What? She glared at him until it turned at least a little sheepish.

"He's um, he's…" Alphonse seemed to be struggling for words. "He's a friend." She got the impression that there was a lot more to the story than that.

It was weird, because Alphonse and Edward looked like they could possibly be Jace's long lost relative or something, with eyes such an unusual hue of gold and glimmering, blond hair to match. Jace's golden eyes came from the blood of an angel running through his veins, and she couldn't help but wonder how they came about theirs.

The waiting after that was torturous. Clary had never even spoken a word to Edward Elric before, yet even she could feel anxiety swirling in the pit of her stomach. She couldn't imagine what Alphonse was feeling. She'd seen herself just how close Edward had been to the edge. He'd literally been hanging on for his dear life when Clary had come in. She could only hope that Magnus would do all he could to heal him.

Alphonse had taken to pacing, but she could see that it was only making him even more agitated. Finally, after a while, Alphonse said, "Do you mind if I look around at the books? It's been a long time since I've been in a library like this, and I wouldn't mind brushing up on some of my shadow world knowledge." The unspoken words were clear. He needed a distraction, desperately.

Clary sensed that the three Shadowhunters around her were a bit confused and curious about his statement, and she knew that there would be questions about it later. The whole circumstance of the Elrics was unusual: if they were Shadowhunters, why hadn't they come to stay or at the very least announce their presence to the Institute yet? And Clary was curious about the lack of runes and rune scars on his bare arms. Almost every shadowhunter she'd met had many runes all over their bodies, especially their arms. All that was on Alphonse's was the voyance rune and his brother's blood.

No one asked their questions then though, and Alec simply nodded as Alphonse went stalking through the shelves, his hands brushing along the spines of the old books.

When he was just out of ear shot, Isabelle began to speak. "I hope that this all turns out okay."

"I trust Magnus. I can understand why Alphonse is anxious, but we all know that Magnus won't let that boy die. And he's perfectly capable of doing something like this." Alec's voice was calm, but Clary figured that this whole thing was reminding him of the time when he himself had been poisoned like this. They couldn't be great memories to suddenly resurface.

There was a bit of silence, but then Isabelle cracked something of a smile. "That boy? You know, he does have a name, and besides, I think Edward is older than you, Alec. Didn't Alphonse say that he was eighteen? And Edward is his older brother."

Alec looked sceptical. "Really? He didn't look older than me…"

Alphonse appeared from behind a shelf, looking vaguely amused, which Clary supposed was better than the expression he'd had before. "You know, he'd probably kill you for that if he could hear you now. Ed has never been one to take jabs about his shortness lightly." Alphonse smiled fondly, as if imagining how Edward would react. His smile lit up his whole face, and was such a contrast to the pained expression he'd been wearing the whole time she'd known him.

He stalked off behind a shelf again, and the four members of the Institute were left with nothing to do but wonder what they had gotten themselves into.


After a while the waiting got a little easier, and conversation became a little less stilted between all of them. At one point they all got so hungry that Alec ordered pizza, although they had to move out of the library in order to eat it.

"Are you even allowed to order food to the Institute," Alphonse asked, halfway through a mouthful of his pizza.

Alec shrugged. He was growing more comfortable, yet also more intrigued with Alphonse and his brother by the second. "I don't even know, but our mom is away for the week for a Conclave meeting, so technically that means I'm in charge. And I'd rather order pizza than suffer through Isabelle's cooking again."

Isabelle grumbled from her place next to him. "I feel like my amazing cooking skills are being ridiculed far too often. Just because you can't appreciate my culinary genius—"

"Izzy," Jace cut in. "Whenever you take to the kitchen, even you can't stomach whatever you make afterwards."

All five of them shared a well needed laugh, and for a little while they could pretend that they were just normal teenagers hanging out and laughing. These were Alec's favourite moments, because they could just be friends without any of the weirdness and worry that came with shadowhunting. He wouldn't trade in being a Shadowhunter for the world, but sometimes it was nice to forget the burdens that came with that life.

Before they could finish their meal, someone burst into the room.

He was quite short, and oddly enough dressed in what Alec deduced to be pyjamas. His dark hair was ruffled, as if he'd just gotten out of bed, and his impossibly dark eyes were wild. The whole just-got-out-of-bed look was completed by the fact that he wasn't even wearing shoes, but navy blue slippers. He looked to be older, late twenties if Alec had to guess, but he couldn't say exactly. He had runes in various stages of fading swirling on his bare skin, and Alec could only assume that this was Roy, the person who Alphonse had called earlier.

Alphonse stood up a little awkwardly as probably-Roy entered the room.

"Angel, I forgot how big Institutes are. It took me fifteen minutes of wandering around this place to find you. I mean, I went to the infirmary first, of course, but promptly got kicked out by a guy who I hope is the warlock healing Ed, and then promptly got hopelessly lost. I'm just glad that I didn't end up wandering these corridors for the rest of my life."

"Ed would be disappointed if that were to happen." Alphonse gave the dark haired man a smile. "I'm glad you managed to get here so quickly, Roy. He'll be so happy to see you when he wakes up. It's been far too long since he's seen you."

Roy nodded, and then sat down next to Alphonse, who also took his seat. He could probably feel all the eyes in the room on him, because he said, "What? Okay yes, my attire is not at its greatest, but it's about 2:30am in Idris, and I didn't exactly have time to pick out my most dashing suit or anything." He looked around at all of them. "So, I'm guessing you're all residents of the Institute?"

Alec nodded and introduced all of them to Roy. "And you're Roy…?"

"Mustang. Roy Mustang."

"Hey, I've heard of you!" Isabelle said, almost excitedly. "You put your name forward for the position of Consul after Malachi died."

"I'm surprised anyone even knows or remembers. But yes, I did. It's always been my dream to become Consul, but I have no regrets about losing out to Jia. She makes a great Consul, and I suppose that someone like her, who's a little more experienced than me, was better suited to the job at the time. Isn't your father Inquisitor now?"

The sour look that must have passed across his face probably said more than words could about his precarious relationship with his father, because Roy didn't press the topic when nobody answered. Robert may have opened up a little at Jocelyn's wedding, but it was only the first step to mending his relationship with Alec, and both of them had known it. He hadn't even seen his father since then.

Alec wondered why someone like Roy, who he now vaguely remembered seeing in Clave meetings and around Alicante, had bothered to somehow come all the way to New York in the middle of the night. He couldn't help but wonder what the relationship between Edward and Roy really was.

"I hope he's alright," Roy whispered, almost to himself.

Alphonse sighed. "Me too."

A sadness and worry hung in the room. Seeing both of these people so worried about someone they cared about, someone who was in virtually the exact same position as he had been a few months ago, made Alec wonder if Izzy and Jace had been like this when he had been poisoned. He knew that they had been worried, but some part of him hoped that it had been like this, because it was so painstakingly obvious how much both Roy and Alphonse cared about Edward. It was etched all over their faces.

The conversation had turned awkward again, all their minds having been reminded of Edward and his condition pretty quickly.

And then, with no warning, Magnus appeared in the doorway. Alec's heart leapt at the sight of his boyfriend, who looked worn out and tired. Alec had to fight down the urge to wrap his arms round the warlock and kiss him.

"Is he okay?" Alphonse's voice was quick and hopeful. His golden eyes were shining.

Magnus nodded, and it was like the entire room let out a breath it hadn't known it was holding. Alec was certainly surprised about the relief that swept through him for a boy he hadn't even met before. Alphonse and Roy's anxiety had apparently been infectious.

"He's still asleep, but I don't know how long for. He'll be fine though."

Alphonse and Roy were both gone after that, their love for Edward, in whatever way that might be, making Alec smile a little as he watched their backs run towards the infirmary.


A/N: I'm sorry if the characters seem ooc, especially Al and Roy, but I guess that their worry for Ed is making them a bit different ahah and also they've had slightly different experiences than in canon haha

Also i am aware Elric and Mustang aren't Shadowhunter names, but I can't help that