Chapter Text
Ed and Al were sitting in their father's study, trying to unlock the secrets of human transmutation; to bring their mom back. Ed felt like he had all the pieces, but the connective tissue was missing. He knew all the components of a human body: "water 35 liters, carbon 20 kilograms, ammonium 4 liters, lime 1.5 kilograms, phosphorus 800 grams, salt 250 grams, potassium nitrate 100 grams, sulfur 80 grams, fluorine 7.5 grams, iron 5 grams, silicon 3 grams" he listed to himself. But the formula wasn't coming together as easily. He didn't know how to account for the soul. It just wasn't enough. Not if they wanted mom back as herself. They needed more.
"Just one leap, that's all it takes" Ed explained to Al, "that's what we need to figure out human transmutation."
Years passed, and during those years Ed and Al had found themselves taking a leap right into Izumi Curtis' tender mercies. Teacher was exacting in her expectations, and strict with the boys' education, but they both learned a lot in that short time. It was the perfect foundation to crack the secrets of the taboo.
She had them draw so many circles that the chalk dried out their hands and the alchemical symbols became muscle memory. She built up their understanding of the basics of alchemy and supplemented their training with lessons on how to live. She and her husband taught them how to cook and clean and create tableware from mud and gave them a gruff kind of love alongside their alchemical studies.
When the boys finally left it was with full minds and warm hearts. But that gruff love wasn't the same patient love of their mother. The path they'd set for themselves was unchanged.
The Curtis' couldn't replace Trisha Elric.
On their return to Resembool, the boys spent weeks using what they'd learned to guide their research. They poured over the books in their father's study, and silently passed papers back and forth with red edits and new notes in the margins. It was a quiet study, so much so that the silence reminded them of Teacher's training on the island. It was a silence so deep and so uninterrupted as they poured over books and passed research back and forth that it was a shock when it was broken.
"Blood!" Ed exclaimed. Al scrambled up, already moving books around to get to the first aid kit in the hallway, but Ed stopped him. He was transfixed by a paper cut welling up with blood on his thumb.
"Look!" he gestured, the blood now leaking down into his palm, "we have mom's blood!"
"Mom's blood" Al whispered back in realization, "but brother, what about- "
"Add a time component to the constructional formula!" Ed answered. It was all coming together!
"That would -"
"Yes!"
This was the answer they'd been looking for. Their blood would provide the necessary genetic soul data, and if they made the transmutation circle look backwards for matching data, then they could make sure the soul was hers. They could pull from a time when her "one" hadn't yet disappeared entirely into the "all."
"This is it Al" Ed whispered "We can bring her back."
Theo wasn't always Theo. At first he was just The Other. He supposed his creator didn't want to get attached before knowing it would work. Van Hohenheim was a tragic man after all. All his people were dead, and his ex-friend was the megalomaniacal homunculus who deceived him and killed them all. A life like that wasn't conducive to forming healthy bonds with others. Though, Theo supposed, his own life wasn't much better in that regard.
Hohenheim created The Other in the wake of the worst moment in his life. The complete devastation of Xerxes. At that time Hohenheim was desperately lonely. The man had lost every connection, both human and not, that he had ever formed in his miserable existence. He had looked down at the empty streets and empty homes of what once was his entire world, and he had felt equally empty. He didn't know who he was.
Was he Slave 23?
Was he Theophrastus Van Hohenheim?
Was he even human anymore?
He certainly didn't feel like it.
The Other was born from that desperate loneliness, that all consuming emptiness. Hohenheim looked out at nothingness, and needed someone, anyone, to look with him. He looked out and saw nothing, so he looked in and pulled. He pulled from the souls within himself to create that someone.
The Other became the only other physical being in those ruins.
But between The Other and Hohenheim, a burden shared wasn't a burden halved. Instead, Hohenheim's burden was transferred entirely. The Other carried the loneliness now, and Hohenheim was free of it.
Hohenheim started making plans: to leave, to explore, to find himself. Hohenheim could no longer relate to the moment of weakness that created The Other. He didn't need a companion anymore.
Hohenheim never got attached, and Theo named himself.
He named himself after a scrap of that too long name. The scrap that was discarded.
In the end, it wouldn't matter that Hohenheim never bothered to look back. Hohenheim abandoned his loneliness in the desert, and set off to Xing. He wouldn't return for a century.
When Theo wasn't still there, Hohenheim assumed the homunculus had done the same.
Ed and Al clapped their hands in a dusty basement and knelt at the edge of the complex array they'd made. The light of the circle illuminated their faces with a pale blue glow, until smoke began to rise in streams around the circumference and dyed the light red.
"Ed, something doesn't feel right" Al's voice shook.
An eye emerged at that moment from the middle of the array, and the smoke coalesced into black tendrils. Tendrils that reached out to touch the boys.
"Ahhhhhhh! Brother!" Al's arm was coming apart like a poorly woven fabric.
"Al! Ahhhhh!" Ed looked down at himself and saw the tendrils pulling at the seams of his flesh. His leg was unravelling. He looked up to see more of the same tendrils finding new purchase in every part of Al's soon to be unwoven form.
"Ed! Help! Ed!" Al screamed.
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A blank white void.
A door.
Ed found himself suddenly transported, and the confusion of the sudden shift from terror to silence shocked him into stillness. It felt like the terror had just been a nightmare.
"Al?"
"..."
"Wait, what was I doing? I jus-"
"Hello" The void spoke.
"Who are you?"
"Oh, I'm so glad you asked" it said gleefully, "I'm called by many names, I'm the world, I'm the universe, I'm Truth, I am ALL, I am ONE, and I am also you"
The door opened, the eye appeared once more, and Ed could hardly hear over the terror rushing through his veins as he turned to see the tendrils reaching for him once more, this time to drag him into the blackness. The last thing he heard before the doors closed on the white void was that strange voice once more.
"I will show you the Truth."
And the truth was what he saw. The truth of everything. Knowledge of everything. It all flowed into his mind, and it was too much. It was too much.
"It's too much!" he sobbed "make it stop!"
His leg was pulled apart.
"Mom, Mom please!"
he reached out and touched something. It felt like skin, like a hand, but then it was gone. Ed was back in the white void.
He didn't notice that he'd brought something with him.
"How was it"
"I see now" Ed muttered, shock having fully taken hold, "My theory of human transmutation wasn't wrong. It's still just missing something. Please, you have to show it to me again!"
"I can't do that, I've already shown you all I can for the toll you've paid." The malicious tone of that creature, Truth it called itself, was enough to bring Ed back to himself. His brother! His leg! He looked down. His leg, which had already unraveled twice, once in the physical world and once behind the gate, disappeared in this space too and appeared opposite him on the otherwise formless being.
"It's the law of equivalent exchange. Right young alchemist?" Truth mocked.
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Ed was back. Back in his own personal hell. The stump of his leg was filling a puddle of blood on the stone floor, and his brother's clothes lay empty beside him.
"No! This can't be happening! What have I done?" Ed cried out, "Please, someone help me!" He just wanted his mom. "Please, Mom." Ed looked to the middle of the circle where his mom was meant to be. Mom would fix this all, she would help him. Help them.
But no. it was all wrong! A grotesquely twisted humanoid form lay where his mom was meant to be. It moved and breathed as if it were in agony, and every inch of it was coated in blood dripping over too-tight skin.
"this... this isn't what we wanted" Ed gasped, horrified at the poor creature they'd made, and even more horrified that their mother's soul may be trapped within. But that thought was too horrible for his young mind to hold, so it slipped away.
Ed turned away from the tortured creature, and as he did he turned to his brother's empty clothes. "Al, Alphonse" he whispered "this is all my fault..."
He was breaking.
"No, dammit! you won't take him too." Ed cried out.
"Give him back, he's my brother! Take my leg, take my arm take my heart, take anything! You can have it. Just give him back. He's my little brother and he's all I have left!" With those words Ed dragged an old suit of armor down to the floor and drew an array in his blood on the inside. He clapped his hands and the blue light exposed the desperation painted across his face.
Ed didn't notice that the broken body they'd created was shining with it's own light behind him. Red crackled across all the misaligned bones, misplaced muscles, and broken synapses. Each piece brutally snapping into place and a humanoid form rising from the viscous puddle beneath it. All it's skin and hair had sloughed off into a mess of biological mass and had been replaced with golden hair and bronzed skin.
It struggled to walk at first. It's steps were unsteady and jerky initially, but they smoothed by the time it reached Ed.
Ed finally noticed it when it placed it's hand over Ed's on the array.
"Who?" he asked, but didn't move. He couldn't move or else he might truly lose his brother forever.
"You may call me Theo" Theo answered, "I heard your cries for help."