Hogwarts.
Swarms of green-eyed black rats flooded the dungeons, just like any other place.
However, the Hogwarts Dungeons, especially the largest Dungeon — the Potions Classroom — were perhaps the only places remaining where the rats carrying the Bubonic Plague had failed to enter.
It hadn't come without a cost, though.
The corridors leading to the Dungeons were filled with the bodies of Wizards, Witches, and… Muggles — soldiers and researchers who had been invited to Hogwarts by Professor Dumbledore to learn and share knowledge, heralding a new era; an era of Magitech!
Most of these people were still alive, wishing for the fate of those who weren't.
No matter how brave a front they had put up against the flood of ghostly rats, they had seen no end to their numbers.
Even now, the horrifying black coffin still hung beyond Hogsmeade Village, spewing constant waves of rats.
Fires burned everywhere.
Survivors had grouped to survive a few moments longer.
Of the tens of thousands of people who had been staying on the Hogwarts Grounds, a third had already succumbed to the magical Black Death. Worse, more than half were on their way to join those numbers, gasping for every single breath as they suffered from the plague.
And the only reason all these people, the survivors and the sufferers, hadn't given up was because they knew there were people at Hogwarts working on a solution to save them all. They knew that even as they fought for their lives, while looking into the ghostly green eyes of Death, the most brilliant minds were gathered in the Potions Classroom at Hogwarts, imprisoning themselves with no way out.
So, it didn't come as a surprise that people would guard that Classroom, despite the rats having a clear advantage within the Castle.
Despite the losses scattered across a vast number of these corridors leading to the Potions Classroom, the black rats had yet to break through the last defense to reach the people within.
Black. Harry. Werewolf-Hermione. Ron. Draco. Daphne with her Pokemon. McGonagall. Flitwick, and many other Hogwarts Professors and students.
All standing on their last legs.
The black rats seemingly had no sentience, letting the defenders annihilate them as they willed. However, their numbers clearly had no end as well, making up for the lack of any strategy on their part many times over.
No matter how many they killed, only a few moments later, more rats would show up.
Magic was mighty.
But it also exacted a toll on bodies and minds.
The children panted, barely managing to lift their Wands.
The adults kept charging forward, sacrificing themselves one after another, giving the children another moment.
And it was all for what was happening in the Dungeon; it was all in the hope of seeing a miracle.
In the Potions Classroom, in stark contrast to the chaos outside, there was utter silence… other than an occasional exchange of words and broken squeaks.
The Hogwarts Dungeons had always boasted an unnatural coldness.
Presently, they felt even colder, a thin mist lingering ankle-high on the stony floor.
Darcie, Snape, Slughorn, and a few other Potioneering experts from other Schools, including a group of Medical Scientists from among the Muggles, were all experimenting to find a viable antidote.
However, similar to the people outside, their faces were pale as well; paler, in fact.
Their eyes had gone red as if they hadn't blinked in days. Despite the uncharacteristic coldness, their backs were drenched in sweat. Then there was the tremor — in their gait, in their hands, in their jaws; an anxiety.
"Instead of a common rat's liver," Darcie suggested, "how about we use a liver from a rat carrying the plague?"
Snape and Slughorn paused, their eyes narrowing.
From the opposite end of the Classroom, a Potioneer already acted, bringing out a black rat from the ones they had hoarded for experiments.
Then, without exchanging more words, the Hogwarts trio restarted brewing the Potion… for a record fiftieth time.
Even then, in their hearts, they knew that successfully brewing an antidote was only half a success.
As long as the Black Coffin kept spewing out all those rats, it didn't matter how many they saved.
With the people being confined to the Hogwarts Grounds, the sea of Black Rats would continue chipping away at their numbers little by little. It wasn't like they had an unlimited supply of ingredients, either. Even now, the never-ending supply of ingredients at Hogwarts had gone so low that merely the thought of counting them would make them lose focus.
It was then that McGonagall and Draco suddenly barged into the Potions Classroom.
"It's gone!" McGonagall screamed. "We can Disapparate again!"
Silence.
Darcie and Snape exchanged a glance, terror flashing in their pupils.
As the others rejoiced, only the two of them knew that this couldn't have happened at a worse time.
Along with the people, the Magic around the Hogwarts Grounds had also been containing the black rats.
Now…
Moreover, right after the fake Madam Villanelle had unleashed the Black Death upon them, they had canceled the Magic placed around the Hogwarts Grounds by Dumbledore as well, hoping that would have let the people escape.
Which meant, not only could the plague-carrying black rats go out now, but just about anyone could come and go as they pleased.
The groups of survivors were still attracting a major chunk of these rats toward them, giving them enough time to continue with their experiments.
Once those survivors Disapparated, most of the rats would storm the castle.
Then… what would they do?
Run or continue with the experiments?
However, just as Darcie and Snape thought of the inevitable, ugly battle with morals, outside, a figure fell from the sky, heading straight toward the Black Coffin.
It was so fast that one could barely see its features.
The only distinguishable thing about this figure was the redness it carried, as if it were drenched in blood.
Slowly, just as it reached a hundred feet above the Black Coffin, another distinguishable thing appeared in the eyes watching it.
An iridescent and jagged dagger.
Then, just as the blurry figure was about to crash, it lifted that strange dagger and…
… plunged it right into the Black Coffin, causing a blinding, black-and-white explosion!