As you wander through the various corridors of Hogwarts you find your way to the most forbidding parts of the castle, where the dungeons looms before you.

You hear a loud scraping from further down the corridor, followed by a grating noise that sounds like stone crashing against stone..

A figure approaches you, wearing robes of green and running his fingers through his long grey beard, looking at you suspiciously.

You, who are you to be wandering these corridors? Explain yourself.