Today it sounded like Quentin said "ARshdon." Makes it difficult to do a search on this word to see if it could be a real place ... Ozchden? Arzhdon? There are so many possibilities.
The hand of Count Petofi has "powers that were granted in the Forest of Oshden." ... Any ideas how the DS writers might have come up with this idea of powers being granted to a cut-off hand, if that's what Magda meant by this?
I had completely forgotten that I had some notes on this that may answer my own question; I discovered them among some papers last night ...
Although the story "The Monkey's Paw" by W. W. [need to check the last name -- but please note, the story in question is NOT by Guy de Maupassant!] is often cited as being the inspiration for the hand of Count Petofi, I tend not to think that's it. For one thing, there's a big difference between a monkey's paw and a human hand.
A more interesting possibility is the Hand of Glory. I believe that this is a concept from European pagan times -- it's a severed hand invested with magical powers.
There is a Hand of Glory on display somewhere in Yorkshire. It is supposed to be the hand of an executed criminal that was cut off and thereby has occult powers.
Perhaps there's no one single "source" that sparked the DS writers' imagination, or it could be an old movie that I don't know about.
In a discussion regarding the Head of Judah Zachary, Luciaphil informed us that the inspiration for the head came from an old B-movie, "The Thing That Couldn't Die." After seeing the movie, I would agree that that seems to be the direct "source" for the head of JZ, in that it's a severed head that controls people with its powers. On the other hand, severed heads that continue to live and talk are common in many world mythologies (including Norse). One might ask what the inspiration was for the writers of "The Thing That Couldn't Die" ... I think it was a short story, but then how did THAT writer come up with the idea?
Perhaps these are more or less archetypes that recurr in stories and legends.