Harry woke up to a burning scar and a great pain in the back of his head.
His wand was laying nearby, under a sink.
Harry pushed himself up and crawled to his wand. Warmth flooded his body, and sparks shot out the end of it.
A jolt went through his mind, a single thought: Voldemort!
He jumped to his feet and raced for the door, bursting out into the corridor!
He had to- to-
He stopped, he breathed, lowering his quivering arms.
He had to...think. He had to find the professors - his mother - he had to warn them.
Harry continued on, now, with a clear sense of direction, navigating the corridors as fast as he could to reach the nearest classroom - the Potions lab he had only just left.
He ran around a corner and down the hall, reaching the Potions classroom at last and banging the door wide open.
Heaving, out of breath.
Snape was there, his mother was there - teaching another class. First years, it looked like. Hufflepuffs and Slytherins.
"Potter - what reason could you have for coming in here and disrupting my-" Snape started furiously, whirling toward the door.
"Harry," his mother cut the man off. "What's wrong?"
"Voldemort's here - he just-" Harry began quickly.
A green light flashed on the walls, and a jet of energy flew past Harry's shoulder, on through the classroom, to strike an unsuspecting Snape in the chest.
Snape fell backwards, crashing against his desk before sliding off to hit the floor with a loud crack.
Harry's mother drew her wand and raised her free hand at the same time; Harry was yanked forward across the room, and a jet of dark blue light flew from the end of his mother's wand to sail past him.
His mother seized his arm and pushed him back, snapping out a firm, "Don't do a thing," then waved her wand at the classroom; the chairs of the students all slid across the room to gather at the far wall - to gather the students all there - and the desks and cauldrons flipped themselves over and flew toward the classroom's exit.
Voldemort stood in the doorway, giving a lazy twitch of his wand. The desks vanished, and a shimmering magic shield appeared to protect him from the contents of the cauldrons, before that, too, vanished away.
Nagini flourished her wand; the door behind Voldemort tore itself off its hinges and struck him in the back, knocking him forward. She jabbed her wand, and a bolt of green flew for him.
Voldemort slashed his wand across himself; Snape's desk flew across the room, faster than the spell, to intercept it in a great explosion of flames and splintered wood. He retaliated with a Killing Curse of his own, in the now barren dungeons classroom.
Nowhere for anyone to go, nowhere to hide!
Harry stepped forward and aimed his wand at Voldemort, crying out with, "Confringo!"
"NO!" his mother shouted, waving her wand in nearly the same moment as Voldemort next began to.
Voldemort summoned up a strange, physical shield of shimmering silver; the Curse struck it, and then shot off to the right - straight toward the other students behind Nagini's barrier. The students looked to be yelling, terrified and panicked, but Harry couldn't hear any of them (he had to wonder why his mother had included a Silencing Spell in her barrier).
One of the student's chairs shot out from behind the barrier, meeting the Blasting Curse head on - and being, predictably, blown apart.
Fragments of the chair flew back to strike the barrier. Those pieces seemed to stick to it, and began to glow and crackle with red lightning. The lightning stretched out across the barrier like spiderwebs, or veins, and then the barrier became solid scarlet itself, and it began to rapidly close in on the students.
Nagini thrust her wand at Voldemort, sending out a Killing Curse again. Then she snapped around and aimed her wand at her own barrier, her face set with sheer concentration. The lightning dissipated, and the barrier turned into something truly solid, like glass or crystal, before shattering. The pieces littered the floor, scattering in all directions. Nagini flicked her wand, and those shards glowed bright white and flew toward Voldemort.
Voldemort sent his silver shield flying forward to take Nagini's Killing Curse - when they met, it exploded into silver vapor - while at the same time he turned toward the barrier shards and held his wand across him body horizontally, his lips drawn back in a snarl.
Nagini's glowing shards met a barrier of dark purple...they began to push and strain, sinking through it a few centimeters...
Nagini twitched her wand, and the shards exploded in a brilliant burst of white light, blinding Harry!
In that second or two of pure, overwhelming light, it seemed as if a dozen things had already happened.
Voldemort had moved further into the room - toward the students, where a second barrier of Nagini's had been put into place, restored again - and Nagini was waving and twirling her wand in spirals and complex motions, as dark purple orbs materialized all around her!
Voldemort's wand tip burst with a bright purple light, and a haze of gas began to spew out into the room.
Nagini waved her wand, sending the purple orbs flying at Voldemort. They entered the spray of gas, and turned a bright emerald; lightning bolts shot from one sphere to the other, connecting them, and at the center a white light was pulsing, growing. The gas was suddenly sucked up into that white light, clearing the room. Then the emerald orbs and the lightning disappeared altogether.
Voldemort had moved another few feet, slashing and twisting, fighting with Nagini as they grew closer and closer to one another.
Harry tried to move to help her, but he ran smack into a shimmering barrier and bounced back again, falling against the wall.
"Mum!" he cried. "Take this down, I can help, I can-"
As he yelled and pleaded and struck at the barrier with fist and spells alike, a part of Harry thought that his mother couldn't even hear him - likely by design. Her design. Just like the other students.
That same part of him told him that his mother needed absolute focus in a battle with Lord Voldemort himself, and that he really couldn't do anything to help with that.
The rest of Harry overwhelmingly disagreed, and continued with its current course of action.
Trying to reach her.
Voldemort and Nagini fought across the last few feet of classroom, reaching the edge of the barrier together.
Just as they did, several familiar figures came spilling in through the open doorway.
McGonagall and Flitwick, and the new Professor Thorn!
Voldemort sent a swift, powerful Curse at Nagini, a strange grey jet of light that looked like smoke more than energy. When it reached her, it split apart and flowed around her, then expanded out to encase her. Voldemort turned away from her and advanced quickly toward the new arrivals, slashing his wand and sending out a massive torrent of cursed fire in the shape of a serpent.
McGonagall and Flitwick raised their wands together to it, and the flaming snake began to twist and tremble, parts of it becoming formless black smoke...
Professor Thorn sent a Curse at Voldemort directly, then waved her wand at him again to no apparent effect.
The fire serpent suddenly exploded into dark smoke, as grey smoke blew out in all directions behind Voldemort.
Nagini was free!
The grey smoke coalesced and flew toward Voldemort's back as a compact orb of swirling smoke, glistening with a golden light in its core.
Voldemort sent a Killing Curse at McGonagall, waved his wand at Flitwick - the stone burst at Flitwick's feet, sending him high into the air amidst burning shrapnel. He whirled around and slashed his wand, and Nagini's orb turned pure black and hit the floor with a clunk, as if it were a cannonball. The orb seemed to become infinitely heavier, cracking the floor and then sinking down into it, tendrils of black smoke drifting off of it, up out of the hole...
Those tendrils surged across the classroom for Nagini's barrier, and pierced it. They went right on through, hardly stopping, and two of their wispy tips struck the chests of two students - a girl and a boy, one a Hufflepuff, and one a Slytherin. And passed on through them.
Voldemort waved his wand, slamming McGonagall against the wall and racing past her, disappearing out the door in a near glide.
Nagini, Professor Thorn, and a recovered McGonagall and Flitwick all turned their wands on the writhing tendrils of smoke.
The tendrils were struck with flashes of light, their insides burst and they were torn apart...only to reform.
The students who had been affected were on the floor, convulsing, their bodies changing color and bubbling, clothes and flesh melting like wax...
Nagini slashed her wand and twirled it over her head like a lasso, drawing a ring of thick purple energy in the air. Bolts of lightning cast off, striking the tendrils. They flowed with that electricity, and then they disintegrated into nothing.
The four professors turned their wands on the source - the orb in the floor - and began casting a variety of spells all together, lights flashing and energy bursting.
Finally, it seemed they had done it; Harry watched as dark smoke rose up from the hole, and disappeared into nothing.
Nagini waved her wand at her barrier, tearing it down, allowing the teachers access to the students finally.
To the ones who were...
The teachers waved and aimed their wands, all kinds of lights bursting, flowing down onto the two students' bodies, enveloping them...seeping into the wounds...
But in the end, Harry knew nothing had worked.
He knew it in the way the stern and harsh McGonagall was crying. He knew it in the way Flitwick was shaking his head and backing away. He knew it in the way Professor Thorn was just...standing there with her wand nearly fallen right from her hand of painted, bright yellow nails, her face extremely pale - and not because of what she was.
And he knew it in the way his mother was down on her knees before the students, her head bowed and her wand still pointed at them loosely, come to a stop in mid-motion, mid casting.
Nagini suddenly stood, turning to walk across the room, right toward Harry. A flick of her wand at her side, and Harry was let free too. Free to run to her, right to her arms.
He didn't want to see that look on her face, he didn't want to feel how she was shaking as much as he was, and he didn't want to feel the wetness of her tears on the top of his head as he buried his face in her chest.
But he was aware of it all anyway.
He hugged her tighter, for her as much as himself.
She probably knew.
Voldemort...had come and gone like a ghost.
No portraits reported seeing him anywhere (though, there were very few paintings in the dungeons, which made it much harder to know if anyone was roaming down there anyway).
No one knew how he'd even entered the castle, or even for what purpose. Just to prove he could?
To strike terror into everyone's hearts, like he had at the World Cup?
For sadistic pleasure and satisfaction?
Regardless of means, method, or reason, the already heightened security at Hogwarts increased tenfold.
Auror teams were brought in to patrol the corridors, the ghosts and paintings were all put on high alert, and a number of other security measures were being implemented within 24 hours of the incident.
Even a very special, secret one that Harry only knew about because of Sirius and Remus.
There was a Map his father and friends had made at school, called the Marauders' Map. A clever, powerful artifact that tracked the movements and names of everyone in Hogwarts.
Apparently, Fred and George Weasley had had it, but after the other day they came forward and gave it to Dumbledore, feeling as if he could use it to see if Voldemort ever came back into the school again.
Dumbledore had brought Sirius and Remus in to help create a duplicate, which the three of them together did manage to make after three days of intense spellwork in the Headmaster's office. A duplicate to be kept by the Headmaster alone, a secret from the entire school. This duplicate had some modifications, though - like an alert system that would trigger whenever it detected certain people in the castle, like Voldemort or any known Death Eaters, or when anyone accessed certain secret passageways in and out of the school grounds (though, Dumbledore had reportedly, personally sealed them all off, and told Fred and George not to use them on pain of perhaps literal death).
It had been reasoned that those passages might be the way Voldemort had gotten inside, since Pettigrew had known of them too, used them before.
Regardless, it was better safer than sorry.
With Snape dead now, Nagini had immediately accepted Dumbledore's request to step into the role full time; she was spending long hours of nights studying textbooks and teacher's guides, even as she figured out how to teach during the day. It was a learn as she went experience, born of necessity.
Speaking of Nagini...
"When I tell you not to do a single thing, I mean it, and you're going to listen to me!"
Near the end of the week, Harry found himself in his mother's quarters, under her harsh gaze of glistening brown eyes.
They hadn't talked about the incident, about any of it - not in any details beyond, "How are you feeling?" and "Are you doing alright?", anyway. Until tonight.
Tonight, when it had all come spilling out.
"What if my barrier hadn't been there? You could have killed any of those children, you could have gotten me killed - do you realize that in that split second that I had to make that decision, I could have lost my life in a dozen different ways? Or that Voldemort might have had a faster, more clever way of getting past my barrier? What if he had killed more than just two students, because you handed him the means to do it? I already had to counteract him because you gave him the means of using it against those children! You forced me to-"
She wasn't yelling - she hadn't once yelled at him in his life - but she was getting close to it. The way she was shaking, the expression on her face, the tightness in her voice...
"Mum, I'm sorry, please, I just wanted to help, I didn't want you to die - I couldn't stand back and let you-"
"Professor Snape is dead, two first year students are dead! You don't get to just go, 'I'm sorry, I screwed this up!' This isn't practice, this isn't homework, this was-" His mother cut herself off, making a choked noise and whirling away. "If I have to Stun you next time we're in a life and death situation, I will, Harry!"
"I- I'm sorry..."
Nagini turned back to face him, stepping forward. She looked him right in the eye. "You. Will. Listen to me: I don't care if it looks as if I'm on the ropes, I don't care if there's a Killing Curse coming for the back of my head - you're going to do nothing except stay out of the way! You will not raise your wand for anything except to put up a shield! Because when you foolishly try to put yourself into a fight that's so far above your paygrade it's not even a joke...you're just a danger, Harry. A danger for me, for yourself, and for anyone else around at the time! Do you understand me?"
"Y-yes! I'm-" Harry cut himself off, bowing his head as tears spilled.
Nagini let a great woosh of air go, her shoulders heaving. She stepped in closer and hugged him fiercely.