I think I'm learning to ask just one question per post. Otherwise many questions seem to get lost in the crossfire 
. Today my question is about Vis Sources. I recently purchased Covenants (not quite in time for the start of our Saga). Using Covenants, I have created a set of Vis Sources in the vicinity of their newly established covenant. The concern I have at the moment is, how on earth are they going to figure out how they work. The Covenant is in a very sparsely populated inland bit of Gotaland in Scandinavia in 940, so I can't rely on peasants or local legend to tip them off. Having used the Vis Sources in Covenants as my guide, the methods for causing vis to be generated at many of these sites is somewhat esoteric. I know they can use InVi spells to detect vis already present if they think to do so, and for those sources within an aura they might even do that, but... For most of the sources... What I was looking for advice on would be about what methods existed already within the rules for decyphering vis sources, what methods do magae utilize within the setting, and how would you play it in your own Sagas. If there were legends they could study and follow up on, that would be one thing, but for sites for which no legends exist (or are well out of their reach)... Would you allow them to research it "generically" like a lab activity (or require them to setup a temporary lab at the site to experiment)? How much information would you give them for a magic lore roll? etc. 
.
Local lore, legends specialisation or myths;
(realm) lore
are your best ways.
Divination/Gruagachan magic are good too.
Usually I assume that by default any vis source purchased with straight build points comes with some sort of readily accessible instruction manual. If the Covent does not have reliable access to this information then I would say that qualifies for the Hidden Resources Boon (which means they are extra points) or potentially one of the Resource flaws.
You are learning, young jedi... 8)
("one question", he said...)
Not sure what you mean by "decyphering" - whether you mean "finding" it in the first place, or (maximizing) harvesting it once found. So we'll talk about both, but harvesting first...
Okay, re harvesting - the short answer is that many SG's blow it off. Once the wizards "find a vis source", and it simply pumps it out, x pawns/year. "Winter: +4 Perdo Vis" it says, and so it just happens, and is automagically transferred to the stores without further comment. Maybe there was a critter guarding it originally or some other challenge, but once a mage touches it it's guaranteed income. These sagas/SG's would rather have action/adventures than puzzles, and the adventure was in finding it - and that's fine.
However, in canon, some vis sources are variable (1-10 pawns/Autumn). Some are very susceptible to misuse or abuse (if most of the magical fish are caught/harvested, the pond will take years to repopulate - if all are caught, there will never again be any fish to breed for next year...), or can be very unintuitive as to how to gather it in the first place. . Some require a trigger or are not immediately obvious (killing an animal and spilling its blood on the ground generates Animal vis, up to 10 pawns for the largest animals). Some is short-lived, and so only exists for a short time and finding/gathering is a lot of luck (on Summer Solstice, a single blossom blooms - that is worth 5 Herbam vis, but it dies and falls at next sunrise, worthless.) Some have perpetual guardians (Willow wisps guard the swamp and "attack" any gatherers - the Imagonem vis only appears at night, and it takes 1 minute to gather 1 pawn...). This type of source is not the "OH! Look what we have!" sort of vis that is perfectly user-friendly - but it does make for more interesting and challenging collections, if that's what is "fun" for your group.
(Many Players just "grab it all", and never ask questions - you can either punish them for this, or remind them (via an "easy" Magic Lore roll) that harvesting 100% of some vis sources has been known to destroy the source.)
Simplest approach - patience and observation. Take 1 vis, or a few, and see what the rest do.
Beyond that, use the InVi guidelines - "raw vis will show up as magical... under any magical detection" and "further increases in level will yield further information". So an effect of (Base 1, R: Personal, T:Touch +1 (target sense), +X levels misc) - or higher as you feel approp - will give "further information" about the vis.
Magic Lore rolls are perfectly appropriate too - set the Ease Factor (p 7) and you're good to go.
But remember the Game Master's rule - if you create a puzzle with only 1 solution, then if the Players don't think of that 1 solution the adventure stops there. If that solution relies on a roll, then if that roll fails the adventure stops there. Having at least 3 different solutions - and at least one of those solutions never closes - is a good rule of thumb for any critical adventure puzzle. (And maybe more, depending if your Troupe are creative/good at solving puzzles/etc.) You can also customize the solution to the magi's spells - that's always a nice touch.
They could also set up a lab on-site and treat it like an item investigation. Pain in the ass and very time consuming (a season to set up a -3 lab, another season to run the investigation), but (if "successful") that should answer all questions.
Now, as for "finding" vis in the first place...
Again, some SG's simply hand it over - players stumble across a circle of mushrooms in the forest, ID them as vis, scoop them up, and repeat every season/year/whatever. But what if they only grow in Spring, and the Characters only cross that area of the forest in Summer?... awkward...
InVi spells that detect "raw vis" may not detect "where raw vis grows". Wise magi have InVi spells with both T:vision and T:Hearing to "hear" vis that is not easily visible. Flying around may put a mage too high up to see such small detail (altho' some InIm or MuIm spells may solve that.) Talking to fae might help. Talking to magical animals might help, but many players see those as one-time vis sources and not sources of information.
Sometimes, some "super-natural" element is noticed in an otherwise mundane environment - everyone in the village lives to be a ripe old age, or all the trees are extra-green, or stones in a wall from X quarry all glow at night. In the end, it's often a story-guide "lucky chance" that causes PC's to stumble across the vis, or across signs of it.
I think part of the problem is that the examples of vis in Covenants suffer from an active attempt to get away from the old "it's a big orange mushroom worth 3 pawns of Imaginem vis" that was common in earlier editions... at least in the sagas I saw. On the one hand being creative about vis is neat and all, but I think they've gone a little overboard in places. I think most vis that gets harvested is of the obvious orange mushroom variety. The weird stuff... like the tears of a greiving widow by a certain lake... would be rare and generally known only because of the legends associated with it. Weird stuff with no legends would probably remain undiscovered unless stumbled upon in the just the right way at just the right time... and the legends would follow.
Well, if you want to have interesting vis sources, design them with a hook (not the game term: Here, hook means something that says hello here is a story worth looking at).
Like:
- you hear that many twins are born in a certain village. Investigations show that young couples often sneak off to meet in a certain cave.
- every juletide, black birds attack the covenant, trying to peck out children's eyes
In other words: If your magi don't go to the vis source, the vis source must come to the magi.
Well, I had our troupe do a sort of "organic", "gamey" Covenant generation. We did a straw man of boons and hooks, which I then expanded with things they would not now about before arriving, and others which were genuinely hidden. Then I gave each magus a couple of pools of BP. One representing personal possessions, gifts/going away presents, etc. A second list representing support sent with them by their covenant or allied, sister covenant(s). The last list represented requests they had made to the magus in charge of the covenant's establishment--basically requests for things to have him, in turn, request from other covenants providing support. The significance here being that all requests were conceptually made in character, grogs from the first two lists would be the only grogs "used to" the magus' Gift, and certain options, namely Vis Sources, were not available. So you could say that all the Vis Sources I've made are "bonus". One of the myriad of motivations going into the establishment of Northreach, however, was the idea that there aught to be a lot of untapped vis sources in the Heathen North, where no* Hermetic Magi had ever gone collecting. Put another way, I don't feel bad making them work for it 
, but I am looking to have a certain abundance of sites.
Ok, several questions all relating to a very narrow topic (Vis Sources) . It's a step in the right direction?
Really the figuring out the usually arcane steps via which the site produces vis, whether they require outside input or not. As you outlined, some require events on particular time tables, some have expiration dates, others require external input, and some might require some combination. Without a significant number of clues, I don't see any of them guessing any of these steps alone. Some could be given hints from contacts or negotiations with local magical or fae creatures, to be sure. I was just wondering, absent lore on a platter (either from local legend or gifted lore), how does a magi go about discovering these details?
Personally, while I have some "orange mushrooms of vis" in place, these tend to be one-shots, much like harvesting magical creatures. You go, you collect them, they are gone. Given the extended fallow period this region has seen, any "rate" of production for such patches is likely beyond the patience of my players, unless I make an impressively large patch, limit it by a supportive aura of limited extent or introduce guardians/caretakers/native harvesters of the source. I hadn't actually thought of all those ideas, so I think I will immediately add a few in that vein, but it still doesn't answer my main question vis a vis hermetic methodology for vis source lore acquisition.
I am totally about punishment 
. I would probably give them a magic lore or magic theory roll, if I did not think it was intrinsically obvious.
I hadn't thought InVi would spell such details out. Would you give them hints and clues to ask more specific questions, or would you just spell it out if they could manage a high enough InVi effect? I recall reading somewhere that even with a high InVi effect you needed to make a magic theory roll to interpret the information you received if it wasn't straight forward.
Personally I tend to shy away from areas too closely tailored to the mages of the covenant (or the PCs in general). It tends to harm my sense of verisimilitude. But maybe I don't know exactly what you mean by "customize[d]...to the magi's spells". You mean making a vis source whose method of harvesting involves or could involve the clever use of a spell one of that maga knows?
So you'd allow them to basically mechanically "win" if they were willing to put in 2 seasons of work. I was wondering if they would really need to create a full lab around it, even. I also wasn't sure if I'd go straight to "here's how it works"... Would you require any related lab total? For instance if a Creo Elementalist were to research an Animal vis source, would you still reveal all the details of the site?
Thanks for all the feedback, Cuchulainshound! As a new SG, it's nice to have reassurances about how to handle topics not "well" covered in the books. Not to mention the added ideas . And.. uh.. how did you know about the crows?
Respectfully, I'd suggest that you reflect on what a Character might reasonably know, vs. what the Player might possibly remember from skimming the books. No one part of Ars is particularly "complex" but as a whole it can be vast, and rules get lost in memory - and, arguably, that shouldn't be a reflection on the characters.
I'd suggest you remind them (or let them roll), and then punish them if they disregard (or really blow it).
Either/or. You know best how "puzzle-oriented" the troupe is, whether they enjoy that sort of thing (and how good they are at it!).
But good stories are all about little coincidences.
So long as it isn't obvious and doesn't happen every time, it's a cheap bone to toss one or another player. Makes them feel like "that spell" was totally worth the investment, might test their creativity/ingenuity to use a spell in a non-combat/non-expected manner, and they gain the spotlight for a moment - all good.
Yeah, something like that. Take a look at the spells the magi have (esp the less "dominant" players), and try to think of some unusual circumstance where "that spell" could find or harvest vis, or do it more efficiently or safer - and then work backwards from there.
Oh HAYel yeah! 2 seasons is a HUGE investment from a Player's perspective, a true last resort.
How to adapt Lab Investigation to "undefined magical stuff" is not spelled out, so you'd have to fake it to some extent. You could have more and more info be discovered depending on the various successful rolls (see p 100), but I'd lean heavily toward giving them at least the basics of what they need. Otoh, once they know how to harvest it "a little", then they might have a roll each year "for added insight". (But remember that Game Master rule - if this fails, where do they go next?..)
And consider the reward - it's only "some" vis/year, it's not the lost City of Atlantis.
(The secret masters of Ars know all!)
<vanishes in a puff of smoke, leaving only the biting smell of sulfer and a scorched piece of paper that reads "light fuse, stand back">
I can't say I ever dealt with this problem - most sources were just "mushroom fields", i.e. raw vis that replenished in time or even just appeared in a set time each year just waiting to be collected. However, I'd definitely let a simple (simple die, low EF) Magic Theory or Magic Lore roll reveal all the information needed, simply because I don't like in-game puzzles. I don't think they're fun. If you enjoy them, however, then by all means make the source one. Design a set of clues (be sure to create more than enough, covering each point with several clues), like local airy spirits or whatnot.
Either case, decide what you want the game experience to be and set the "rules" accordingly. No need to be consistent, either - some places the gathering method may be obvious in-game to anyone with Magic Lore even though it's esoteric and weird to us, while in other places a fairly straight-forward method would actually be due to extremely unusual Magical conjunctions so the Magic Lore EF would be unrealistically high, and it can only effectively be revealed through adventure/puzzle-solving. Whatever works for the given adventure and for your group.
I'll generally leave the "setting up a lab around the source" as an absolutely-last resort. I'll also reveal all in such a case. Wasting two seasons is a huge investment.
Spells, now... well, I don't expect my players to have a "How do I harvest this raw vis source?" spell. But I see no problem with allowing such "further information" with extra magnitudes; again, I'll allow it easily since I don't like making these things into puzzles.
In so, so many questions about Ars, this is the most important rule. More important than canon or RAW, more important than "self-consistency" or logic, "what the Troupe enjoys" is the bottom line. (Just so long as the the Players remember that the SG is part of the Troupe, and vice versa!)
In many (Spring) Sagas that I've played in or run, the SG runs one early "solve the vis riddle" scenario, possibly as a warm-up night to get everyone on the same page re spontaneous casting and combat, and lets that be largely representative of the effort needed for all the others, just as a reference point. ("Remember all the trouble you had in that swamp with the willow-wisps and the Imagonem vis!?")
Then all future efforts at that and other sources, esp any that are "contested", are abstracted, the SG allowing a roll vs. an Ease Factor based on a narrative description. Nothing is again RP'd out in detail (unless there's plot complication, or a botch?), but the strategy is decided and the EF based on that. "Same as we always do..." is fine, and the PC's get a narrative "in-character" assessment as to the success, and consider if their strategy needs tweaking for next time. This is sim to a "5-10 pawns/year" source, only allows the Players (to feel they have) more control over the final outcome. And the scenarios can move on to focus on larger issues.
But I've also been in sagas where "You get 10 ignem, 10 aurum, 10 aquam and 10 terram vis/year", and the storyline dives immediately to the main plot. That works too (and "better" for things like Play-by-Post, where the action moves slowly enough as it is).
I tend to treat these kinds of investigations as a season of study/practice/exposure and give the character the experience points and knowledge of how to harvest. And feel free to pick the ability; area lore, magic lore, and even magic theory are usually appropriate.
And the nature of the study can be living at a site for a season to observe it, interacting with the locals to learn how they think things happen, or researching dusty tomes. Whatever you like.