Disclaimer: The worlds I write about herein belong to J.K. Rowling, Glen A. Larson, Ronald D. Moore, and David Eick. I do not gain any money by writing this.
Authors Note: I am writing this for my own personal edification and to try to annihilate that silly bit of logic that J.K. Rowling uses to make it seem like the Wizarding World cannot use electricity. This will be a one shot.
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It was a beautiful day in the highlands of Scotland. At a mysterious hidden castle no one was any the wiser that anything nefarious was about to happen. However by the end of the day, that beauty was going to be no more.
Up in the office of a man who looked like he better belonged in the novels of one J.R.R. Tolkein rather than the real world, the fireplace suddenly flared green and voices could be heard emanating from within…
"GAH! SOMEBODY H-!"
"Anyone! Anyone Please!"
"No, I don't want to—"
And just as suddenly the fire went out. The old man looked up from where he had been sitting with some concern at what had just happened when suddenly there was a violent and loud booming noise unlike anything the old man had heard in a very long time…
"No, that can't be…" he started to say and began to stand up, but suddenly all the glass in his office shattered inwards and he was knocked off his feet by the concussive boom that issued from the window just behind him.
=0=
Meanwhile down in the courtyard of Hogwarts, a large portion of the student population had just witnessed the entry into the atmosphere of a rather large spacecraft. The Muggleborn and Half-Bloods though were the only ones that even knew it was a spacecraft, and they only knew it was a spacecraft based on the fact that it arrived from the upper atmosphere and appeared to be holding position about 500 feet in the air.
This spacecraft had the most peculiar star-point pattern to its design. One Muggleborn Student, Hermione Granger, was looking at this ship and mouthing "No, no, please god, no!" over and over again as she at least seemed to realize what she might be looking at.
Just as suddenly as it had arrived, several hundred much smaller craft began swarming out of the ship and raining all hell down upon the young Witches and Wizards. Some who had been standing within the Castle Entry way scrambled back inside one Teacher ran behind the doors and passed a wand over the outward ward stone that would send the castle into complete lockdown. That wouldn't help any of the students that were caught outside unfortunately.
Of the 800 students, 30 falculty, and 100 House Elves, 100 students died in that initial volley.
=0=
When the Aliens realized that they could not breach the Castle's defenses with their dogfighters, they brought in the heavy artillery. Ground-Units were brought down. Each armed with heavy assault blasters. These blasted relentlessly at the main doors while a humanoid model stood by watching. It took several hours, but finally the doors were battered down through the use of their heavy assault blasters. Thus began the culling of Hogwarts.
You might be asking, how the Cylons were able to operate within Hogwarts at all given the high magical output on the grounds surrounding Hogwarts. Well, the reason might surprise you. You see, the Cylons spent many, many, years learning how to operate within the confines of a Thermo-Nuclear Apocalypse. As such they have made all of their systems out of circuitry that is hardened against various types of radiation. In doing so, they just happened to create a cocktail of circuitry hardening that rendered them immune to magical feedback. This is how the thirteenth generation of Cylons was able to conquer the Earth nearly five millennium after the fall of Caprica.