Vis Extraction from Non-Magical Auras

I know that the RAW on p94 state that vis can be extracted from an area with a magical aura but I have noticed that sometimes writers use the term "magical" when they should probably say "mystic". Whats the basic practice in most campaigns?

Basic concept is Hermetic Magic and the Gift is originated from the Magic realm.
As a rule of thumb I would only allow it for a maga if her gift is also aligned with the realm in question... and avoiding in general the extracting from Divine Aura idea.

I can easily imagine a Merinita mage extracting Faerie Vis from Faerie Auras, I would only ask for a minor breakthrough.
Of course, as per Covenants, this could be easily recognized as syphoning / robbing by the locals.

I generally go for a hermetic magus can only extract vis from a magic aura. Holy Magic from RoP:the Divine specifically allows extraction from a divine aura, so I wouldn't let anyone without it extract vis from a divine aura.

Same with darkwing, but I would add to the list of virtues to do that the Virtue from Hedge Magic Natural Magician, I understand than that is the useful part of the virtue.

Extracting Vis from infernal auras will produce infernal vis, IIRC RoP:I correctly.

Thanks for your feedback guys. I forgot about the references to extraction in ROP:I. The idea of a breakthrough to extract faerie vis is something I'll incorporate. I appreciate all of your assistance.

Realms of Power: Faeries also suggests that extraction from a Faerie aura is possible.

As far as the Faerie vis extraction causing the aura to fall, I'd rely upon Realms of Power:Magic to determine whether or not the extraction causes the aura to fall, and if it doesn't fall the presiding Faerie doesn't do anything.

I've always thought it is possible to extract vis from an aura. Extracted vis is just aligned with the aura from which it is drawn, and may not work as intended...

By LoH p.14f the Minor Breakthrough Confluence of the Realms "provides the understanding needed to extract vis from any of the four realms" plus some other insights.
So extracting useful vis from a non-magical aura requires successful Hermetic research quite achievable by the dedicated specialist magus.
Extracting (RoP:tI p.19) vis prava from an Infernal aura is possible without such a breakthrough, but this vis is extremely dangerous and useless for those not aligned to the Infernal - leading to their corruption or destruction.

Cheers

It is interesting you quote that section Jonathan because it was the section I reading before I started to mull over the issue of vis extraction in the first place. That raised a few issues for me which were as follows:

  • Did the writers meant extraction in the same sense as the RAW in ArM5? In the game there are clearly two ways to extract vis. The first is by simply finding and taking (which any person could theoretically do, whether they are aware of its nature or not)) and the second is from "concentrating the magical energies" to make vim vis - p94. The second seems to be a special aspect of hermetic practice.

  • A faerie aura becomes a faerie aura in the first instance (as it is suggested in RoP:F) because faeries hang out in a place which is a different from how an aura becomes magical or infernal. Basically a faerie aura has vis in because the faeries living there have shed it (accrued) or flogged it from a magical aura (encased).

  • A magical aura is formed because vis becomes the source of the aura in the first place; the source of a faerie aura is the might of the big kahuna faerie living there and an infernal one because someone fornicates with a black chicken on the spot. So if you were going to extract vis from a faerie aura in the hermetic sense, it would appear that you would be leeching it from the big kahuna?

I appreciate the reference to the LoH virtue since I had not read that previously.

Vis does not follow laws of conservation. Magical auras generate magic vis. Faeries generate vis when they "consume" human vitality, divine simply generate vis and the infernal gets vis from corrupting human or divine powers.
Generally if you are taking faerie vis the faeries want something in return, generally vitality in terms of the story through which you interact with them. Since people gain experience through this process it is generally a win win situation- generally. Sometimes the human winds up dead or injured...

In terms of the source of an aura, how do you see the law of conservation having relevance? I see it in relation to some types of vis. For example vis bought into an infernal aura becomes tatined RoP:I 18. And it is correct that faeries are attracted to vitality sites which is in turn how they create an aura because of their continued presence in that place. However the aura does not directly come into existence because of vitality. Nor does the aura produce vis like a magic aura. In my reading of RoP:F the vis produced is simply the by product of their finding, deception or death.

With magical auras it is quite straight forward because the aura is usually bought into existence through vis in the first place. The vis is like an oil well. You are simply extracting and refining the product of the aura. The only extracting I can see from a faerie aura is walking around and finding the by-products of the above.

WRT faerie auras, one type of faerie aura is created when a certain type f faerie is present (one with the virtue of an extended glamour). If vis were conserved then to extract vis from the aura would have to take it directly from the might of that faerie, since there is nothing else supporting the aura.

Let me clarify this. Your saying that if vis could be conserved (which in your view it cannot) you could take it from the might of the faerie? Therefore since vis does not follow the laws of conservation it cannot come from the faerie? So the point your making is that it must by necessity come from somewhere else other than the might of the big kahuna in the aura???

No.
If the vis comes from the big kahuna faerie then, typically, each pawn of vis would lower that faerie's might by 5 and by extension the aura by 1. However in ROP:faerie we find that with a pretense cost of 10+might a faerie can gain a minor virtue (with the aid of a creative human) which can be "increased might score" which increases a faerie's might by 5.

So what I am saying is that just because it is coming from BK's aura does not make it a zero sum game where BK has to lose all of what the magi gets. The aura falls by one due to the insult to the BK's essence, not because of some mechanical conservation of vis/might.

In theory a truly adept magus could extract enough vis from a faerie aura to turn around and give to someone with free expression and actually net the BK positive growth in their might and an overall increase to the aura. Because it ain't science, it's magic.