Chapter Text
The instant before the bright green light of the Killing Curse hit him, Harry closed his eyes and let go. The jeers of the Death Eaters faded and, as his Dad had promised, there wasn’t any pain. It was over. Finally, finally it was going to be over. He could be with his family again.
When he opened his eyes, he was in a dimly lit room with three huge pillars stretching up into pitch-black darkness. There was an eerie stillness in the place; even the candles were burning in complete silence.
As if summoned by that thought, a blood-curdling scream cut through the air, making Harry jump in fright. He looked around one of the pillars to see a bassinet on top of one of three plinths on a corner of the room, and something was crying inside. He approached the bassinet warily, extending his arm to turn it around to at least try to soothe the baby.
"Don't touch him."
Harry jerkily pulled his hand away and spun around, feeling his heart jump to his throat. He would always recognize that voice. Though when he turned, the person in the room with him was his brother… and it wasn't. He looked a few years older than he had ever been and his clothes were different. He had a crown of golden laurels and a tunic decorated with animal skulls on his shoulder and in his belt. His feet were bare and left a trail of cooling embers as he walked.
"Zag?"
The man tried to smile, but the slump of his shoulders and the crease of his eyebrows belied the expression.
"Yes. It's me, Harry."
"But… how… what is going on?"
Zag grimaced, still looking far too old for his body. It was an expression that Harry had seen before and always dismissed; now he thought that he shouldn’t have.
“Harry, I… I am not human. I have never been. Remember that argument I had with Hermione, back in our first year? I am Zagreus, one of the chthonic gods. My first father is Hades, Lord of the Dead. My first mother is Persephone, Queen of the Underworld. You’ve known her as Kore.”
“What? But then…” He tried to make sense of it all, and couldn’t. “Why?”
“Before you were born,” Zagreus said, “there was a prophecy. It wasn’t Trelawney’s. It was older and a lot more powerful. It spoke of a mortal that would be given power over the gods. Harry, Riddle was only ever going to be a distraction. You always had a greater, truer destiny. You are the Master of Death."
“You mean… the Hallows?”
"You already knew they were real. You know they are powerful. And Death… Death is my family. I couldn't simply let a mortal wander in and try to leash him again. So I made a deal with the Fates, to watch over the chosen one. Over you. Once I had their blessing, it was easy to create a conduit: so Lily had twins, and no one ever suspected that one of them was different."
"So then we… were we ever brothers then?"
"We are, of course we are!" The god lurched forward, grasping Harry’s shoulders. His hands were warm and calloused and a knot of fear in Harry’s stomach relaxed under the touch. Zagreus continued.
“I… At first, yes, I wanted to make sure that the chosen mortal wouldn’t be like… that they would not abuse that power. But, Harry, I’ve known for years that you would never do something like that. I know I, we can trust you with the Hallows.” Zagreus looked at him, with all the determination that Harry had always found comforting. “We have grown up together; we have fought together. You are my brother. Blood doesn’t change that.”
Harry found that he believed him. Even with this change, he knew Zag well enough to recognize his sincerity. For the first time in days, Harry smiled, slumping to rest his head on his brother’s chest, feeling his arms wrapping gently around him. The hug was almost unfamiliar since their heights were now different, but it was still just what Harry needed. He closed his eyes, letting go of the desperate fear that had carried him until this moment in time.
"Now what happens?" he murmured at last.
Zagreus flinched. Harry looked up, not expecting the guilt he could see on his face. "I wish I could tell you that you had a choice to stay… but your thread wasn't meant to be cut in this battle. You must go back."
"Can't you come back too? Please? You’ve already done it once. No one has to know what happened!"
Zag looked at him and for the first time the shadows of the room seemed to lift. His red eye gleamed eerily but the sorrow on his face made Harry’s heart break again. "I wish I could. I'm a being of the Underworld, brother. I don't belong in your world. The only reason I survived for so long before was because of Lily's sacrifice. My cousin destroyed that vessel. There's no going back from that."
He detached one of the gold-red leaves in his crown and it shifted, becoming a golden brooch as soon as Harry touched it. He held it carefully in his hands, marvelling at its strange warmth.
"Harry," Zagreus said. “When you return, there will be one final fight, and then it will be over. So live. Live a long, happy life, see the world, do whatever you want to, regardless of what destiny says. I will watch over you from here; and know that when your time comes, we'll meet again in the House of my father."
Looking up, Harry clutched the brooch against his borrowed wand. He tried to keep his voice steady, but still, the words were lost in his throat and he couldn’t stop the flow of tears. Zagreus moved forward, and gathered him in another hug, one that was a little desperate, but Harry didn’t care. It was still his brother. Always.
"...Do you promise?"
"I promise."