The prison here was under extremely tight security.
Even Dumbledore had to undergo a series of checks, for no other reason than that the Wizarding World had far too many things that could be used to impersonate others for all sorts of purposes, including, but by no means limited to, Polyjuice Potion.
And here, they held the most dangerous man recorded in thousands of years of history of magic, a man who had nearly overturned the entire Wizarding World.
Su Er was also inspected. Although he did not understand German, judging by the attitude of the man responsible for questioning him, the man was not friendly at all. He made it emphatically clear that only Dumbledore could enter, while Su Er could not.
Nevertheless, Su Er was eventually allowed into the Castle, with Dumbledore vouching for him.
Oh, of course, that came at a price: his wand was taken into temporary custody.
This place only looked like a castle from the outside. Inside, unlike Hogwarts, it had none of those wondrous magical things. It was more like a decrepit stone house abandoned for centuries. Naturally, no one had the leisure to sweep and clean here, either, and every surface exposed to the air was covered in a thick layer of dust.
"Skurge!"
Dumbledore was completely unaffected by this place. After looking around for a while, he raised his wand and spoke the incantation. With the incantation reinforcing it, the magic became even more powerful.
An invisible whirlwind swept up the dust, and the stones beneath it finally breathed fresh air.
Under the influence of magic, the dust condensed into a mass of gray-black matter and was guided out through a glassless window.
Su Er secretly gave it a try, only to find that his magic felt like the waters of