Just doing a quick poll of player magi in various sagas. So I can finetune my NPC magi.
The following hypothetical situation:
In the moat surrounding your Covenant (or other associated water feature) lives a large man-eating magical Pike.
You can harvest the Pike for 4 pawns of Vis (and the safety of your Grogs).
Or if the Pike eats at least one person per month, once a year it regurgitates a human skull containing 2 pawns of Corpus Vis.
What do your Magi do?
Let a dangerous creature that requires deaths inhabit your (the edge of) your Covenant to get yearly vis? In my current saga we would kill it right away.
First the fact that you must sacrifice 6 people, some of which are likely to be covenfolk, for every pawn of vis gained means it is a very inefficient source. Also since in involves sacrificing people then there is a good chance that it will be considered Infernal.
Having a large dangerous predator that wants to eat people active near your home is never a good thing. There is also nothing to prevent the pike from attempting to eat the Magi if they are ever in its area. And it definitely will attempt to eat covenfolk. You could lose some highly skilled personnel and the moral of the people will take a big hit.
I think even most "evil" Magi would not want to keep it around since the amount of deaths per pawn of vis it would provide is so low.
Perhaps if people envision the Pike as part of the Covenant defences.
Or perhaps I should ask, what is the ratio of people eaten to Vis created that your PC magi would comsider acceptable?
I think the type of covenant will also play a factor. A covenant ruling lands, or inbedded in a noble's castle, could probably get away with condemning criminals to death to harvest the vis, and at that point the philosophical dilemma kind of goes away - if you're going to behead or hang a murderer, why are you concerned about throwing it in the moat to a gruesome death if the creature is not believed to be of infernal origins? The problem really becomes one if you believe the pike can prey outside the moat (like Troy points out) or if you need to find victims. That's going to generate a lot more discussions, and make many magi uncomfortable. But there are canon vis sources requiring human sacrifice, so this wouldn't be the first one that gets fueled anyway...
What does the Pike subsist on if it isn't fed men? Fish and birds wandering into the moat?
I imagine our covenant keeping it then, and even supporting stories of it to scare away bandits and covetous neighbours.
Feeding it people on purpose for vis? Nah!
My players would kill it and be done with this potential nonsense.
Alternatively, some more open minded magi could want to breed it : see if it's possible to get better yields, or to make the offspring's produce vis by eating less contentious food.
Would it count as a vis source if placed in a laboratory, even if not provided with victims ?
Many Covenants, my own included, breed or at least keep dangerous creatures as a vis source. What I was attempting to point out (and did not do a good job of) is that these creatures are normally contained in some way. They might be pinned in or caged. They might be kept in a special pond with some sort of defense. They might be on a deeper regio level in which people do not travel to.
With the Pike in the Covenants moat, every time someone enters or leaves the Covenant they are passing close to or over the creatures domain. What happens when a messenger or Redcap stops and waters their horse? Even if they are not wounded their horse surely might be.
Now that is a story idea. Try to explain at the next Tribunal why Redcap Piscis Cibum got eaten by an overgrown fish in your Covenant.
If you want to use it as the means for executing criminals (great point Temprobe) then capturing it and putting it in something like a special pond where there is much less risk of people accidentally getting eaten would be wise. While I find it unlikely that most Covenants are in a large enough community to have a criminal condemned to death every month it is possible. What happens when you are going to miss a month and thus not get the vis that year? Will the Magi just grab some random person?
Kill it for the vis within it, and then make a big BBQ where we feed the magi and the grogs with the flesh of this tasty fish.
My group found once a chair. If you sit in the chair you sleep forever (if nobody push you out of the chair). After 3 month a body on the chair crumbled, leaving Co-Vis (works only with a living body).
The magi had long and often discussions, if and how to use the chair (only evil persons, only criminal or enemies or unliked peoples...) - but in the end they got corrupted, using random kipnapped peoples to let the Corpus-Vis Production running ...
I don't think that is the right question, as it depends entirely on the availability of victims. As @temprobe points out, the victims could be criminals that few people would have any qualms about condemning to death.
I could imagine a covenant building up some pagan cult who practices human sacrifice.
I could also imagine a warrior cult who would raid their rivals to feed their pet.
The question is then one of demographics. What is the density of elligible victims?
Now, I am not suggesting that the typical magus or covenant would engage in any of these approaches. Even executions of criminals may be tricky, since it may be better to keep a safe distance to mundane justice.
But every scenario is plausible enough for a Tytalus.
Keeping it as a defensive aid is more interesting. This is not so much a moral issue, but rather a matter of risk assessment. Unfortunately, we need a lot more information to assess risk. How well can it be contained? Would it ever leave the moat?
My maga would probably kill it right away.
It's a potential risk, and not worth it.
If it could be used as a friendly guardian, releasing vis only when fed, she would argue to keep it, not due to the vis, but to the guardian factor.
She'd probably be okay with giving it people sentenced to death, although... The people you'd feed to it are not "dangerous" to a magi, and thus better used as ressources, even if you must scare them for that.
So the only people fed to the beast would be very rare exemples of "This one crossed me too many times", in which case the vis would just be a nice side bonus.
For what I thought was a reasonably straightforward and simple hypothetical question, people seem to be getting strangely picky over what I would have thought was mostly irrelevant details.
I did not use the word "sacrifice". Strictly speaking, I did not even say it had to eat live people. Lets just say it has a taste for that juicy mammalian delicacy that is Human flesh (from the Pike's POV).
The Pike, being a fish, has difficulty preying on anything not in the water. It might be able to reach out of the water a foot or so to grab something. Livestock looking for a drink might be a at risk.
One would expect the Covenant to have some sort of safe route to enter and exit - A tall draw-bridge, a Mercere Portal. an invisible sky bridge, a deep water and fish-proof tunnel, or something along those lines
I would assume that the Pike subsists on whatever lives in the water source that supplies the moat.
The Covenant could be on a peninsula reaching into a lake/swamp, or some other similar arrangement.
Actually, if the details of the hypothetical are so important to your answer, would you mind reporting the details that would get your Magi to answer one way, and the details that would get them to answer another way.
I would keep the fish alive. Preserve the bodies of those who die naturally and keep prisoners slated for executions until we had a set of 6, then feed the pike for 6 months in a row to make sure we get the vis. Place a sig by wherever the fish is located in Latin (and the local language if you have allies in the area) which says "Beware of fish!", and probably create an enchanted item that will cast a continuous InCo spell on the lake to keep track if anyone wanders in. If we weren't going to use the fish as a security feature we would probably fence off or wall off the water feature.
TBH, I don't think the pike's accepting dead victims makes an awful lot of difference. Most people in Mythic Europe would expect a proper Christian burial, even for their enemies. Only the most heinous offenders would be denied one.
Therefore, neither of the two PC magi I currently play would even consider feeding the fish with human flesh in return for vis.
I could, however see a pagan magus constructing a cult around the pike. People fed to the pike live on its magic, or something like that. I suppose different pagan traditions may be more or less receptible to such a custom.
I could also imagine the apprentice I currently doing whatever in this situation, on account of being whimsical ... and brought up a pagan. But I hope his attitude is an exception in the Order.
On the question of if we would keep the pike as a watchfish, I think that depends on two things. The availability of vis and the danger of the creature. Both the two sagas where I play are vis rich, but I imagine that magi in Rome would be more likely to harvest the vis given the opportunity. One of the covenants is on an island. If the pike is a threat to boats, it would have to be hunted down; otherwise not. The other covenant, incidentally, has a dry moat and a genius locus who insists on letting the grass grow continuously across. But if things were different, a wet moat and a watchfish sounds useful to keep
I think the big thing is that the key issue can be broken down into two parts- protecting people from the fish- which does not in fact require the fish be killed to accomplish that goal, and the single harvest versus long term payout of vis. The need to feed bodies to the fish is a fairly incidental issue in a lot of campaigns that simply reduces the amount of vis returned for the long term harvest based on the availability and suitability of corpses. At a certain point (probably requiring massive levels of ability in the arts), you could magically mass produce bodies to feed the fish and come out ahead since spells will produce x10 bodies per extra levels of magnitude. 6 bodies per pawn, level 30 ritual spell to create 1 body, means it costs 6 vis for one body, 7 vis for 10 bodies, 8 vis for 100 bodies, 10 bodies will produce 1 2/3 pawns of vis, 100 bodies will produce 16 2/3 pawns of vis (over a period of 8 years), and becomes a net gain of just over 8 pawns of vis.
You just made the very argument for why I choose the word "sacrifice". You actually expect the locals, both covenfolk and others, to learn about the fish and take steps to avoid being eaten. Therefore if you want that 2 pawns of vis a year you will have to feed it a person every month. That person already being dead does not change things much. Christians and especially the clergy will likely react badly.
Chances are that the Pike is most likely a Fish of Virtue. This means that it might not be limited only to being in the water all the time. There is the possibility that it could have a power which lets it leave the water and survive for short periods of time. That could be anything from leaping from the water to attack something and being able to return, up to the ability to short term breath air and swim through it as if it was water. Even if it does not have such a power at the start, it could develop such if feed.
Now I am becoming interested in turning this hypothetical fish into a real story event.
My current magi is somewhat self-righteous. I could imagine when presented with such a scenario him saying something like "Making the correct moral choices is what differentiates the best of us from the basest of us. "
The beast is dying.
The risk of somewhat accidentally falling in the moat is too high.
Feeding a human to a beast, every month, I don't care how much vis, what are we barbarians, or men of virtue?
This wouldn't bother my maga much.
But it would bother covenfolks, lower morale, stuff like that.
If she didn't think about it by herself, but someone did, she would agree that this would be bad.
So the need for vis would have to be overcome that, and she would certainly second a proposal to engineer a "The dead live on through the fish" cult
My guess is that most Magi would kill the fish. Most societies frown upon desecrating dead bodies unless they belong to someone who has done something terrible. Even those magi who has no problem with the morals of this will probably see it as a big risk if someone else (covenfolk, neighbours, the church, the order) finds out and reacts negatively.
But of course some magi (desperate for resources, risktakers, really ruthless) will see it as a good source of vis. For example in the Rhine Tribunal Roznov already sacrifices live humans and at least Dankmar would also sacrifice dead bodies without thinking too much about it in my opinion.