Vis harvesting spells query

Games Discussion Ars Magica
1

Now take a situation where you have a Vis source where the Vis is spread out throughout an object in such a way that if it were a beast you would need to cast 'gather the essence of the beast'.

Supposing also this same Vis source had more Vis in it than you can safely remove. Because the Vis in it focusses the magic and creates more Vis. Kinda like a congealing process.

Now you could probably blag jut casting gather the essence of teh beast if you are greedy and to hell woth the consequences... but a sane magus is never gonna do that. So how does he extract 'some' of it. I should add this follows on from a conversation last year about poto-Vis - which I know is not to everyone's taste but this is the situation.

Rego VIM: Base 10: Move Raw Vis from one physical form to another without
needing a laboratory.
Range +1 (touch)
Duration +0 (momentary)
Target +1 (part)
final lvl = 20
This would harvest a KNOWN quantity of vis form a source of proto Vis (or dispersed Vis) - as
in - removing that which you decide based on what you know by other means.

Rego VIM: Base 10: Move Raw Vis from one physical form to another without
needing a laboratory.
Range +1 (touch)
Duration +0 (momentary)
Target +1 (part)
Req: Intellego +1
final lvl = 25
This would determine a safe amount to harvest and then draw it
out. That would be what the intellego requisite adds.

Now, one of the players quite rightly pointed out that target:part is probably not necessary because you are affecting the whole source. Then again, you are not taking formthe whole pool. I wondered what otehr people felt and where they would go with this. I moved twoards removing the 'part' requirement formthe second spell as the spell actually scrys the whole thing then choosesa bit. I wondered about leaving the frst one as part and having it remove a single pawn.

Any suggestions?

2

I always thought that affecting magic with magic in a "gather the vis" process should be extremely easy with hermetic magic by how vis sources are described in the core books. Several sources are said that "well you gather the stuff with magic et al" without miuch details and without assuming you have specific spells for it, so I assume that sponting or a minor trinket that takes hours to prepare in the lab (not counted towards distractions from the lab) is a clear possibility here.

As such I would dsay that individual is enough.

Cheers,
Xavi

3

I often have renewable vis sources that require a "seed" to stay "renewable" - you harvest all of it, it's done. Puts a damper on dull players, and makes any vis source a minor and ongoing side story, as the more subtle players take their time to understand it before disturbing it.

Target:Part would do it - and/or an additional magnitude for "complexity". Just that simple imo.