I vaguely remember that vis can be harvested from a dead magus, but can't recall how much or if this is canonical or someone's (perhaps my) house rule. Does anyone know?
thanks,
Matt Ryan
Only if he is wearing the vis as a ring or something. Unless the Mage is aligned with the Magic realm ( with a might score) then they would have no vis.
We allow vis to be harvested from a dead magus, and calculate it based on his two highest arts-- generally providing a number of pawns equal to the form bonus along with a pawn of Vim vis for each point of warping. It's not much, but we feel it reflects the exposures of intense study and the effects of all that magic use. A powerful magus might yield +/- a rook, not enough to start harvesting magi. 
In our saga, Tainted with Evil has also been used to "color" vis gathered from a fallen magus.
-Ben.
That's close to how we've been doing it as well, but I'm currently curious if its canonical or just fan-invented.
(thanks)
Matt
I have only just started playing 5th edition, but have played 3rd for many years. In my 3rd edition campaign vis can be harvested from a dead Magus who has started taking a longevity potion, or who has acquired Twilight points. The rule of thumb that I use is that the number of pawns that can be gained is equal to one fifth of the Magus's Vim score. The Art(s) of the vis is usually based upon the Magus's magical specialities.
Obviously if the dead Magus had a 'personal vis source', then that can be harvested.
I can't say...My primary SG's been playing since about ArM3, and so some of his rulings can blend between editions with a healthy dose of his own invention. I can't recall anything in any of the canon for ArM5 that would state this, though now you've got me curious, too.
-Ben.
As a SG, I'd not allow vis to be collected from every dead magus - I don't think killing magi deserves a reward. Non-lethal resolutions (breaking and entering, intrigue etc) can also lead to getting a comparable reward.
Anyway, vis is pretty useless compared to books, a change of the local aura, an apprentice or a familiar, or a useful companion or a pact with a local nonle/fairie etc.
Hi,
If you're a Diedne, quite a bit.... 
Anyway,
Ken
I do not recall reading this anywhere, so I guess it is a fan made rule. Not a bad one I would say! Gibven the berserker habits of some of my players I would hesitate to include it IMS, though, or we would see something really nasty with high penetration cast on a Grand Tribunal or something....
Cheers,
Xavi
I don't think it is canonical, in 5th Edition at least.
Now, I'm not your rules lawyer type and I'm not too big in mechanics either, but I can't recall any of the sort ever being mentioned. Only creatures with Might (of any sort) yield vis.
Harvesting dead magi for vis goes way back, but to the best of my knowledge was never included in any of the core rules (1st-3rd editions, can't say for 4th or 5th); perhaps it was in a supplement, or just included in the myriad house rules. So the amount varies from troupe to troupe. IMS we generally award an amount based on a number of factors, mainly a magus' arts at the time of death (around 1 pawn per 5 levels of the art), any magical affinities (Te/Fo affinities usually grant more than the "lesser" ones), personal vis sources, and the like. We consider a mage's specialties and affinities for the form of the vis (so a Creo master with a Cr 12 will definitely yield some Creo vis) but if nothing jumps out and says "It's this kind" then Vim is the default, or perhaps a half Vim/half Corpus cocktail. It's one of those things that can (and perhaps should) vary from mage to mage.
Mages are aligned with the Magic realm, hence they benefit fully from a Magic Aura. Their Arts are their Might score (and parma to a lesser extent).
Excellent point. Demon-tainted, faerie-blooded, etc. may also spice up their vis.
Another good idea, IMO. We used to rely solely on a magus' Vim score until someone juiced a dead wizard who had a lowly 6 in Vim but had four other Arts all over 12 (and one was a 16!) and received a paltry sum. We house-ruled on the spot in favor of dominant Arts rather than one arbitrary Art. But whatever works.
Of course killing magi deserves a reward. Why should one be rewarded for killing a pixie, but not a magus? Purely on the technical merits, anyway. As for the moral, political or social consequences of such an act that's for the SG to punish/reward as they see fit. Maybe I don't want the PC's in my story to kill the dragon, I want them to work out a diplomatic deal, but they kill it anyway. I still give them the vis, but the greater rewards are lost to them. The same should go for the magus. A good SG makes the negative consequences of a "wrong" act feel real, not like you're holding back the candy bag because your players did the "wrong" thing.
I don't think there are any RAW that describe how much vis would be in a magus. However, it is not true that it is only creatures with Might that yield vis. Many vis sources involve harvesting vis from creatures or plants at particular times. There is no suggestion that those creatures must necessarily have Might.
If needed, I think that I would make the amount of vis in a dead magus pawns equal to their Warping Score. But I'm not sure that I would make every magus contain vis. Of course, most magi would probably be carrying some vis too.
Good point. As I said, what I have is a rule of thumb; as a storyguide I will make a judgement based upon the particular circumstances.
I agree.
Perhaps it is also worth pointing out that PCs might harvest vis from a dead Magus without their having been responsible for the death.
There are so many recipes that make good use of a dead magus.
Not to mention that harvesting vis from a magus might involve processes that feel (perhaps accurately) an awful lot like desecrating a corpse. Time for those players to clarify how their characters feel about religion, sin, reputation...!
Back to the main point: thinking on the magical aura rules in RoP:M, there seem to be three categories of thing that generate magical auras: creatures with Magic Might, (nearly) perfect specimens, and astrologically resonant things. Magi don't seem to automatically belong to any of these categories (even though magi would nominate themselves for the second one), but individual magi might. (It's interesting that Warping usually has the effect of making the target a worse specimen: from that perspective, allowing a Warping score to correlate with vis in the corpse is more questionable.)
But Bjornaer always taste of chicken.
Excellent point. My current magus couldn't care less, a corpse (even his dead master, or Bonisagus himself) is just food for worms. But my first maga would have been stricken with horror at the very idea.
These are rules I ignore for the most part IMS. Magical Auras can be created by whatever the SG says created them--the above suggestions being three possibilities--but they are clearly defined as either Magic, Faerie, Divine, or Infernal (we don't use Reason Auras, and neither should you...LOL). Wizards are clearly in the Magic Realm (3rd edition stated this explicitly, perhaps 5th does not?), though they benefit from other auras to a lesser extent.
And I'm not too familiar with Warping Scores or their effects. IMS magi accumulate Twilight Pts. and the more they get the weirder they become, but this is left to SG and player to have fun with, not set down in any rules. The tradeoff, it seems, is that although you get more warped you have also (presumably) gotten some good benefits from twilight. But not necessarily. Seems like double jeopardy to me, but I'm unfamiliar with those rules. The "old" concept of Twilight accumulation meant that the more a wizard experienced it the more magical he became, until he literally "became" magic itself and just...went poof. So IIRC basing some vis gain on a warping score sounds reasonable, since he's been marinated in powerful magic.
And Flambeau are always well done.
Mmmm, Marinated mage.