The dog had been killed. Blood was dripping from all of its three snouts, pooling on the floor next to the trapdoor. Snape surmised that it had been blasted against the far wall rather than hit with the Killing Curse; a dark red stain suggested as much, and the Avada Kedavra left no bloody traces. The harp they had played to calm it when they needed to check on the Stone lay broken in a corner; a sneering message to anyone who had ever used it. The trapdoor was a scorched, gaping hole in the floor.

“You’re not going in there, Albus,” Minerva McGonagall said. She was trying her best to sound firm, but Snape could tell that the sight of the dead Cerberus had shaken her badly. “You simply can’t-”

“But I do, Minerva,” the Headmaster said, not unkindly. “I would ask you, Filius and Pomona to make sure your Houses are safely in their common rooms. Quirinus, if you’d be so kind to take care of Slytherin House for Severus.”

Quirrel, who’d been lingering close by the door, nodded hastily and left without a look back.

“I’m going with you,” McGonagall announced. “I can help-”

“- by making sure everyone’s safe,” Dumbledore said firmly. “Severus will accompany me.”

“But Albus-”

“Could you for once spare us your Gryffindor heroics,” Snape erupted, far more viciously than he’d intended – not that he felt sorry for a second. “It might have escaped your attention and perhaps you don’t care, but there’s one of my students down there with Lord Voldemort!”

McGonagall winced as if she’d been struck. “Severus, how can you-”

“Please!” Dumbledore did not raise his voice, but they both fell silent at once. “Minerva, I need you to trust me and do as I say. Please.”

She didn’t look happy, but nodded. “Very well, Albus. But if you’re not back within two hours-”

“- I trust you to do the right thing and evacuate the school,” Dumbledore finished quite calmly. “If Severus and I do not return, it means that our students are no longer safe here.”

McGonagall’s face lost color, but to her credit she merely nodded. “Be careful down there.”

“Certainly,” Dumbledore replied, smiling slightly. “Oh, and do make sure the children are not overly worried, Minerva. There may be no reason to scare them unnecessarily.”

Snape could have screamed. “If we could finish with the chitchat, Headmaster-”

“Of course you’re right, Severus. Minerva…”

She left, not without a final, worried glance at the pair of them. Not willing to waste another second, Snape strode over to the hole that had been the trapdoor, wand in hand. It seemed to have been hit with a forceful Diffindo, judging by the scorch marks on the floor and the splinters of wood still attached to the bent hinges. Snape lit his wand and pointed it downwards. Far below, he could see an uneven shape on the floor, like a huge molten stump.

“I believe Tom disposed of the Devil’s Snare the same way he did of Fluffy,” Dumbledore said, his eyebrows drawn together. “He always did resort to crude violence whenever he felt pressured.”

Snape said nothing, merely cast a Cushioning Charm that would break his fall and jumped. Air rushed past him as he fell through the darkness, and a rustle of robes from above told him that the Headmaster had followed suit. They landed on the air cushion Snape had created, a few inches above the burned stem that used to be one of Britain’s largest Devil’s Snares.

Dumbledore stood and shook out his robes. “Lumos.”

The entire place bore witness to violent destruction. As they walked towards the Key Chamber, an acrid smell grew stronger and stronger, and on entering the chamber, Snape saw where it came from: The keys, each carefully bewitched by Flitwick and enchanted to behave like humming birds, had been blasted from the ceiling. Molten and shapeless, they littered the stone floor of the chamber, their burned wings emitting the revolting smell that filled the room. The door on the far side of the chamber no longer existed. Like with the trapdoor, only a scorched hole had been left by the spell that had hit it.

Much the same was true for McGonagall’s chess game. The chamber was filled with the rocky debris of the chess pieces, which had been blasted to bits. Snape looked around, and not for the first time wondered why they had bothered at all. He, if perhaps not the other teachers, knew perfectly well that Voldemort’s world was not one of childish games and fair sportsmanship. Tom Riddle had always refused to play by any rules life set him, so why this? Why set up a number of elaborate “tasks”, as in a school competition, for a man who enchanted decaying bodies to come to life and kill the families of those who stood in his way? What had they expected?

“Symbols, Severus,” Dumbledore said softly, and Snape suspected that the old man had been reading his thoughts again. “They matter more than we think. He can blast apart any protection we set up, but he cannot force us to stoop to his level, no matter what.”

Snape shrugged it off, barely sparing a glance at the dead troll or his own potions riddle. Not that there was much to see anymore. Nettle wine, poison and Flamefreezing Draught were pooling on the floor around the shattered bottles. The black fire that should have protected the entrance to the last chamber had been extinguished, no doubt by an All Flame Vanishing Charm. Only few wizards knew how to cast it, but the Dark Lord had never had problems mastering spells other people didn’t.

They slowly approached the opening to the Mirror Chamber. This, Snape knew, was one obstacle Voldemort could not blast out of his way without destroying the very thing he had come for. The only real protection the Stone had been given. Perhaps the “symbols”, as Dumbledore called them, had fulfilled their purpose simply by putting Voldemort off his guard.

“Harry,” Dumbledore said softly.

The boy was standing in front of the Mirror of Erised, his back to them. He saw them coming, of course; Snape saw those white eyes following their every move in the mirror. The bloodied lips parted in a parody of Harry’s grin.

Severus, the voice filled the room, even though Harry’s mouth never moved. You’ve been missed.

Snape trained his wand on the figure in front of the mirror, whose blood-flecked smile widened. Oh yes, Severus. The boy… he is quite fond of you. “Don’t hurt Professor Snape!” It’s all he’s been telling me.

“You won’t get what you’re here for, Tom,” Dumbledore said as if Voldemort had never spoken. “I believe you realize how the mirror works?”

You believe you’re so ingenious, Dumbledore, the voice hissed. Tell me, does it hurt? Does it disappoint you that your Golden Boy cares more for your little turncoat there than you? Doesn’t it smart that he was Sorted into Salazar’s noble House… my House?

“Your House, Tom? It may have been, when you still called this school your home. You lost that privilege a long time ago.”

At that, the boy turned around, his smile gone. You are wrong, Dumbledore. I never called this school my home. I merely called it mine… and I still do.

“Oh, I am quite aware of the complexities of your delusions. That does not change the fact that you will not see through the mirror, so to speak. The Stone is quite safe.”

Harry’s hand shot up in an angry gesture, and flames rose around the chamber, burning too bright to be natural fire. Oh, is it?

 “Yes, I believe so. And while I may have swayed your mind once with a burning wardrobe, you would be amiss to assume that your little display will change mine.”

We shall see, Dumbledore… Harry’s hand made a beckoning gesture towards the flames. A ball of bright fire floated towards him, growing larger as it approached his outstretched hand. Just before it touched his palm, the boy drew back and threw the flames with all his might, hurtling them at Snape.

“Protego!”

Dumbledore and he shouted the spell at the same time, but the ball of flames passed through their Shield. As a reflex, Snape threw up his arms to protect his face when the fire enveloped him. Yet the horrible heat, the pain he’d expected didn’t come. All he felt was a strange itching on the exposed parts of his body, where the flames were touching his skin. He stared at his hand, waiting for the blisters to break out and the skin to blacken, but nothing happened. He was burning alive without feeling a single thing.

Dumbledore threw a rapid succession of spells at him, none of which made the slightest difference, except that they seemed to amuse the thing inside Harry’s body.

You’ll wear yourself out, old man… only I can extinguish the fire. And I will do so – as soon as young Harry looks in the mirror and tells me where to find the Stone!

See for yourself, Harry…

The milky white sheen on Harry’s eyes disappeared, and suddenly the boy was back, gasping, shaking.

“Harry!” Dumbledore called. “Harry, do not listen-”

But Harry ignored him. He was staring at Snape, eyes wide and frightened. “Professor…”

He is not hurting, the voice filled the room again. It had changed, Snape noticed. The malice in it was still there, but veiled, its tone gentle and almost caressing. And he need not be hurt at all. All you have to do is look in the mirror and give me that which is given to you… I promise, Harry…

Snape opened his mouth and found that the flames did not stop him from speaking. “He is lying, Harry. He’ll break his promise to you, just as he broke the one he made to me. He killed your mother, your parents. Do not listen. He- aaaahh!”

Suddenly there was pain in his left hand, pain so terrible that he could not keep the scream inside. The flames ate into his skin, leaving unbearable agony behind. He could not help wildly shaking his hand, could not help screaming-

“Professor!” Harry tried to run towards him, but his broken leg gave and sent him sprawling on the floor. “Stop it – leave him alone and I’ll give you the Stone! I promise!”

Do not lie to Lord Vordemort, boy. He knows.

Harry screamed, and then turned around, crawling back towards the mirror. “Harry, NO!” Dumbledore shouted, but Harry wasn’t listening, pushing himself up to be able to see his reflection. He stared into the mirror for a second, then reached into his pocket, and suddenly his eyes changed, becoming white and insane once more.

The horrible pain in Snape’s hand disappeared along with the flames. He fell to his knees, and watched through a haze as Harry’s hand emerged from the boy’s pocket, clutching a scarlet object that shone in the fire light.

Now, old man, Voldemort said, forcing Harry’s body to its feet. It seems that for once, you were wrong.

Snape looked at Dumbledore. There was a strange look on the old face; one of defeat and infinite sadness. And even before Dumbledore raised his wand, Snape knew what was going to happen, and he did something he had never done in his life: averting his face because he didn’t want to see.

“Avada Kedavra!”

The flash of green filled the chamber, illuminating it for a split second. A dull sound followed, surprisingly loud, of a body falling and hitting the stone floor. The flames around them flickered, hissed and died, and the room was plunged into complete darkness.

Snape got to his feet. He did not know how he had retrieved his wand, or whether he had dropped it at all. He lifted it and conjured the same blue light he’d conjured all those hours ago, when he and Harry had left the castle for the forest. The Bluefire rose and hovered like a ghost, waiting to be directed by his wand.

Dumbledore stood motionless. He held his wand limply at his side, his fingers slack around the wood. “Severus…”

Snape did not look at him. He walked past him and over to the body on the floor, sprawled in front of the mirror like a doll a careless child had thrown aside. He knelt down next to it, picked up the Stone that had fallen from the boy’s hand and tossed it away into the darkness. Then he pocketed his wand, gathered the small, limp figure into his arms and stood.

“Come, Albus. We must return.”

For a moment or two, it seemed as if Dumbledore would not be able to move. Then he finally did, walking like a man in a dream, following Snape through the broken chambers and towards the trapdoor.

The boy in his arms felt very light, and in the blue light Snape had conjured, his face looked  peaceful. Not as if he were sleeping; Snape had seen too many dead bodies to find consolation in that particular illusion. There was a thin trickle of blood under his nose, and his face was too blank, too expressionless for a slumbering child. But peaceful, yes. Murdered for the greater good in a game he was too young to understand, too young to play himself. Murdered because he’d wanted to protect the one person who deserved it the least.

They were waiting at the trapdoor, McGonagall and Flitwick, and thankfully they began asking their questions only after they’d pulled Snape and Dumbledore up with a charmed rope Flitwick had conjured. Snape spoke to none of them, ignored McGonagall’s horrified gasp when she saw what he was carrying, ignored Dumbledore’s soft “Severus, please” and Flitwick’s sobs. He walked away from them, towards the hospital wing where Pomfrey was waiting. He didn’t speak to her either, merely walked past her and towards the last bed on the far side on the room. There he laid the boy down, careful to arrange his arms and legs so that he would have been comfortable. He took a blanket from a shelf nearby and covered Harry up to his chest, making sure to tuck in his feet after he’d removed the boy’s trainers.

When all of this was done, Snape sat down on a chair next to the bed, put his head in his hands and thought of nothing, nothing at all.