On the one hand, these appear to be individual, tied to someone's particular type of magic. On the otherhand, there are mysteries confering you one, lineages confering you one (the Tremere being the most known)... And I've sometimes seen people here discuss foci in various topics, from longevity to wards to just about anything, as something frequent enough to be taken into consideration, OOH-wide.
So I've got 2 questions:
How frequent are magical foci in your saga? Does anyone have one? Are they rare, the mark of a precious and great talent in a goven field?
How frequent is a given focus in your saga? Even if everyone has a focus, your saga will be very different if these differ for each person (aside from the Tremere and Mysteries foci, which'll then be very unusual and powerful for a group) than if, say, half the flambeau have a focus in Creating Fire and 1 magus out of 10 a focus in Longevity.
Everybody has a magical focus IMS. If not it would be hermetic science, not hermetic arts. There are divergences in how your Gift manifests. Most (supernatural) people also has at least a minor supernatural ability.
About 3/5 has had a Focus i think. My own characters is more like maybe 1 in 4 or 1/3.
Out of those, maybe 1/3 have had more than one Focus.
I tend to prefer personalising a magi´s magic with less extreme means, even if a Focus is much more powerful.
A focus in Emotions, a focus in wild animals, a Potent Magic in destroying "foul spirits" (demons and fae) from a Twilight episode, A Mythic Blood minor focus of Circular Wards that the player feels a bit hampered by, but is coming around, and a former player who had a focus in metals, and another Mythic Blood from another former player conferring a focus in Ghosts.
Whether by "direct" choice of the virtue Magical Focus, or "indirect" choice e.g. because of House (Tremere) or Mythic Blood, in the sagas I've seen the breakdown is about:
15% Major Magical Focus
50% Minor Magical Focus
35% No Focus
Magical Focus is a very popular virtue in our sagas, because it allows a large boost in power if you choose to "taylor" your magic properly. It's also great from a "story" point of view, because it really pushes personalization. Minor Focuses are more popular than Major ones, both because the general feel is that you get more "bang for the buck", and because the limitation to a single Major Hermetic Virtue really is a big deal.
There are a few canon sources that indirectly hint at numbers. It all starts with the comment within the virtues that you cannot have a second focus, no matter the source. That is far different from even Major Hermeic Virtues, in which case the restriction is on character creation and not other sources. Then we turn our attention to certain groups, the most notable being House Tremere and House Verditius. House Tremere's case works both ways. First, it suggests the focus isn't inherently very common, or they would have a lot of trouble finding apprentices. However, since the entire house share a common focus, that makes sure a large fraction of the Order has a focus. House Verditius's confraternities follow a similar trend, but since the numbers are much smaller the issue is less convincing. About 1/3 of the house's members are in confraternities, and about half of those train foci, which means they only have to deal with 1/6 of the magi in the house.
All of this seems to indicate that magical foci are probably not inherently very common, but that they end up being reasonably common through training of one sort or another. I would interpret this as new magical foci being relatively uncommon and magical foci from training being relatively common.
There's certainly nothing very concrete there, but there are hints at what is likely.
Yes, of course, foci that are gained through "training" are going to be as common as the magi who belong to the groups that have that "training". Although, there is a question as to whether the training produces the focus, or whether only people with the right focus can be successfully trained.
Something else to bear in mind, is the in-character perspective.
If two magi have a minor focus in, say, "wolves", we might use the same game mechanics to represent it, but the magi might view their foci as being something entirely different --- one magus might consider his focus an aspect of his heartbeast, and the other maga might consider her focus to represent a mystical consequence of the fact that a wolf was killed by her father on the night of her conception. Or some other in-character explanation.
Equally, in-character, "a focus with wolves" might be seen as essentially the same thing as "a focus with badgers", and both be seen as very different to a "focus with fire".
That wasn't the point at all. The point was how common those groups are and that they cannot train someone in their focus if that magus already has a focus.
In the case of my Verditius examples, according to canon it is clearly via the training. In the case of House Tremere it seems highly unlikely that so many individuals would just happen to have such a focus innately. If that were the case there should be lots of magi outside of Tremere (including non-Hermetic ones) with the same focus because lots of the Gifted individuals they find to apprentice would have such a focus if we're saying it's innate.
Now if the debate were about lots of individuals having an innate but undefined focus, one that had to be honed later, that could work. But if we're talking about foci in particular areas only, I think it's pretty clear that training is dominant.
Although, the rule is that you can't have two foci. So, it is possible that the process of training can replace one focus with another.
You are probably right.
Although it is conceivable that the House Tremere has aggressively found and targetted all the appropriate apprentices. And we don't know how many inappropriate apprentices House Tremere has been forced to kill because they didn't turn out right...
It appears from the first answers that I was not very clear.
As some people have understood (and interestingly answered), I didn't meant "among your players", which may be quite exceptionnal and different from the average magus, but "in your saga, in the OOH".
This'll affect things like:
For those campains where most to all PCs had a focus, are such covenants of "magus with focus" an exception or the rule?
Aside from House Tremere or mysteries, is your focus in Longevity/wolves/fire/emotions/metal/whatever a rare thing that'll mark you as "the LR/wolves guy/fire/emotions/metal/whatever" of the OoH, or is it common enough that you can expect several other magi to have it?
With the condition that I'm not the Alpha storyguide, my impression is that foci are rather uncommon in "our" OOH. I am the only player with one (in longevity, he wants to live forever, be forever young ) and this makes him attractive as a Longevity expert in the Rhine tribunal at around 25 years Hermetic age.
So my guess is that you we have the official foci (Verditius and Tremere) and some specialized talents spread around, but from those we have met and know of only 10-20% have a focus.
As I said above, IMS most magi have a focus, be tnem PCs or not. That makes everybody share a system, but the Gift does not manifest equally in everybody. So most NPCs are defined by their focus since it shapes their magic.