I’m somewhat uncertain as to the practical impact of the “ambient magic” limitation. Looking over it in The Practical Enchanter (p. 126) – where it’s part of the Arcanum Minimus feat, aka the non-Eclipse version of the Compact metamagic theorem – the main drawback seems to be that it increases the casting time, but that’s not really a factor for a continuous-use magic item, so I’m not sure why it’s then worth a discount when creating such items.
Also, given how these are non-combat items that make use of very low-level spells, I’m curious how many of these could be charms or talismans? While most of them are continuous, which makes them strong for either or those, their low level of power/functionality makes it seem like that would be possible?
Well, with spells of levels 0, 1, and 2, adding the Ambient Magic limitation to a device that casts them is basically taking 50% off the price in exchange for raising the activation time to at least one minute. It could, in theory, be much longer – which would offer a possible explanation for those items that need to be worn for a day before they start to work.
While that does have little effect on uses/day items beyond making them useless in combat, on unlimited use items that keep casting useful spells it means that the spells go off no more than once per minute instead of once per round – effectively reducing what can be accomplished by 90% to achieve that 50% price break.
To look at the individual items…
A Straw Golem simply takes a minute to activate. Of course, this rarely matters – but Straw Golems are very vulnerable and are of very limited use in any case even if they can keep going for twenty-four hours a day. After all, any normal six year old child is stronger, faster, smarter, just as capable of “taking 10″, and enormously more versatile than a Straw Golem. Straw Golems are best used for tasks so repetitive and boring that the kids keep quitting. In their case the price break is a purely mechanical thing with no real game impact, although, fittingly enough, the same could be said for a Straw Golem.
When it comes to Charms and Talismans, they’d probably fit in as one of the many, MANY, versions of the Animated Implement (Charm).
With the Owl Post the Ambient Magic limitation means that you can only send messages or packages once every minute or two instead of once every turn or two – saving 500 GP at the cost of giving opponents as minute to try and intercept things before the second spell goes off and a 90% reduction in capacity. Admittedly, that will rarely be of importance – but if you’re running a kingdom or providing messaging services for a major city, you may well want to pay the extra 500 GP.
The constant repetition of a pair of first level spells is beyond a Charm, or even a Talisman’s powers. You could make something like a…
Quill of the Hawk (Talisman): (2 + Level /3) times a day you may use this quill to write an address, or a description of a location, on a small letter or package. The package so addressed with transform into a hawk, take wing, and fly for up to two hours to reach the target location before turning back into a letter or package.
The Beasthorn does not have an ambient magic limitation since, if you are trying to bring in a sizeable flock, herd, or similar group of animals, and you can afford to buy a specialized magical device to make it quicker and easier, making it take ten times as long to save 100 GP didn’t seem reasonable.
A Beasthorn makes a reasonable Talisman – although I’d be inclined to let a character with a good Perform skill push the limits a bit.
An Automagic Loom is using a spell that processes one cubic foot of material to turn fiber into cloth. (While a square yard of cloth generally represents a lot less material than a cubic foot, I’m presuming fluffy skeins of yarn). Applying the Ambient Magic limitation saves 187 GP by reducing the output by 90% – casting the spell once per minute instead of once per turn. Presumably this also makes it a lot easier for the operator to monitor things and keep up with the fiber demand.
In theory such devices can easily be used to break the d20 economy – for example, instead of ten looms use one that’s ten times as fast and have the other nine weavers take “aid another” actions instead of making cloth on their own to produce superior cloth exponentially faster – but the d20 “economy” comes pre-broken anyway and you don’t actually need a magic loom to pull that trick.
As a Talisman, this is simply a version of an Industrious Tool (Loom).
A Ring of Aesculapius saves 180 GP by reducing the number of patients that you can treat by a factor of ten. Admittedly, that will rarely have any impact unless you’re dealing with a massive plague, but then there’s very little other point to buying this item at all.
This, once again, is really beyond the reach of a Charm or Talisman. They’re just not up to producing an endless font of even low-level externally-directed spells. You could, however, make something like a…
Pulque flask of Patecatl. When filled with agave sap these hammered golden flasks will ferment it within a week, transforming it into 2d4 doses / sips of Sacred Pulque – a marvelous tonic which functions as both a Relieve Illness and a Relieve Poison spell. Unfortunately, to be effective a dose of Pulque Tonic must be consumed within five minutes of being decanted.
An Elfin Harvest Basket saves 36 GP with the Ambient Magic limitation with no particular cost associated; taking a minute to activate it rather than a turn means next to nothing as a part of a multi-hour project. It is taking advantage of the rule simply to make it available to the peasantry for a reasonable price. Of course, it’s an item that’s does nothing but take up storage space for a sizeable chunk of the year.
Skipping the Ambient Magic limitation and going to “Unlimited Uses” would only cost another 324 GP – but once you start doing THAT, you might as well invest a total of 2160 GP and get some similar items for the Turn Soil, Sow, Ward versus Vermin, Weedkill, and Thresh Hedge Magic spells. Then you retrain all of the peasantry save for a few factory-farming specialists to do something more profitable than farming. A few years after that you just get an Endless Sideboard and forget farming entirely. Ergo, this item is designed for the benefit of the peasantry, rather than to make them obsolete for the benefit of the local lords.
If you just want some treasure for a higher-level Commoner… 216 GP invested in items that cast each of those spells once per day, six straw golems (one to use a swape to raise water, one to maintain the irrigation ditches and direct the water to each field in turn, one to remove rocks and condition the soil, one to keep up the field-boundaries (fences, walls, and hedges), one to tend your barn and animal pens, and one to feed and milk cows, 405 GP), and a few more convenience items and for less than 1000 GP you can have the complete “gentleman farmer” package, where you stroll around, look over your well-tended fields and flocks, and do very little actual work.
Given that – at base – these devices use externally-directed second level spells, they’re a bit beyond what can readily be done with Charms and Talismans. Of course there are all those legends about helpful fey who help with various kinds of work if properly propitiated. Brownies help with chores, Moniciello helps with wind and vineyards, others help plants grow, and so on. Ergo, a set of Charms or Talismans allowing the user to contact such creatures and ask thing to help out seems reasonable; various Elfin Song Charms can replicate the effects of a level zero Hedge Wizardry Spell if left alone for at least an hour with the task to be accomplished – given a small (typically food or some trinket) offering to the spirits and a DC 14 Knowledge/Nature check. Various Elfin Song Talismans can similarly duplicate a first level Hedge Wizardry spell given a DC 16 check, a slightly larger offering, and at least three hours alone – or a second level Hedge Wizardry spell given a DC 18 check, an even nicer (if still minor, such as a small bottle of alcohol) offering, and being left along until the next day.
A Millstone saves 25 GP by requiring a full minute rather than a single turn to reduce a bushel of material to powder – but this hardly matters for its intended uses on a once-per-day item. It DOES matter with unintended uses – for example, when some adventurer wants to create a dust explosion, fill the air with powdered (whatever some creature has a severe reaction to) to try and get it into its lungs, or otherwise get clever. If they want to pull off stunts like that, they’ll just have to pay another 25 GP for a custom version which works in a single turn.
A Millshaft uses the modifier to reduce its potential output by 90% – which is still sufficient to meet the needs of some 3000 people. Doubling the price to meet the needs of 30,000 would be more efficient of course, it would also be a fearsome bottleneck, as was illustrated by Wittigis’s siege of Rome in 537, where stopping the flow of water which drove the city’s gristmills was nearly catastrophic for the defenders. Paying a little more for a more distributed system is probably well worthwhile.
A Millshaft is far beyond a Charm or Talisman’s power to duplicate, but a Millstone makes for a reasonable charm. The instant version that’s of interest to an adventurer would be a Talisman.
A Cleansing Ring or Fountain uses the Ambient Magic modifier for purely mechanical purposes – to reduce the cost. Reducing the amount of laundry and polishing you can do in a given length of time is pretty meaningless when there is no actual need to ever even mention doing any laundry or polishing in the first place. This is basically a certificate that says “I am nice to the servants / I don’t have an appropriate cantrip and want to be ready for court at a moments notice / I want to show off my prosperity / I want to justify adding a “neat and tidy” line to the description of the local inhabitants” – and so there’s a minimal game cost for something with no game effect.
The Fountain is, once again, too powerful – but the charm list already includes the Cleansing Wand, the Polishing Cloth, and the Mandarin’s Pin. (I suppose a Talismanic version of the Mandarin’s Pin – perhaps an Imperial Clasp – which kept the entire party clean, neat, and well-mended would make a reasonable Talisman).
The Contraceptive Amulets with the fancy names are ridiculously cheap – to the point where the ambient magic limitation saves less than ten gold pieces. That’s a purely rules-mechanical thing given that it normally takes more than one minute to get to the point where pregnancy becomes a possibility and to the fact that the spell need only be cast once a day for males and once a month for females. Of course, many settings note the existence of various herbs, teas,, charms, prayers, or other cheap contraceptive methods (often without specifying a price), while many more are simply silent on the issue.
These, of course, are intended to place the issue of “what effect will cheap, reliable, contraception have on the setting” front and center – and are as cheap as possible in order to make sure that the impact of having them around is as great as possible.
The Charms and Talismans list already includes a reliable contraceptive amulet. It does not include one with the “virginity restorer” function, but a Talismanic version should suffice for that if you would like it.
Cleansing Candles don’t use the Ambient Magic limitation because the Prestidigitation spell seems to indicate that each tiny trick is a separate, if very small, act of magic. Otherwise why would “tricks” be plural and why would the spell be any better for magical practice than any other cantrip? Ergo, applying the Ambient Magic limitation might reduce it’s ability to clean by 90% – and the ten minute figure is already based on cleaning one cubic foot within it’s range each turn. Making it slower would not fit in, given that it is obviously a pure luxury item in any case.
A version as a Charm seems entirely reasonable.
A Carcass Chute (and it’s possible leathermaking “attachment”) uses the Ambient Magic limitation to slow things up a bit, reducing the processing rate by 90%. As usual It’s still far higher than there’s any reasonable need for outside of a major city, but it is very convenient and far less smelly than conventional methods.
This will not work as a Talisman – the power demand is simply too high – but a blade that helped you cut up an animal far more quickly than usual is already on the list as an Industrious Tool.
Finally, Composters use the Ambient Magic limitation to reduce their processing capacity – and remain odoriferous for a minute as a result. The household version isn’t really very important and the high-speed model is beyond the power of a Charm or Talisman again. If you really want to make compose with Charms and Talismans… get a Warding Cartouche Charm (which makes a continuous Unseen Servant) and have it collect the trash and tend the compost heap.