What is Hermetic Architecture *for*?

I'm working on a magus for a game on a different forums. Part of his planned progression is an eventual initiation into the mystery Hermetic Architecture. I'm really struggling to understand what its practical use is. What benefits does hermetic architecture have over enchanting a smaller object that simply casts a spell on a structure target, or even a boundary target via other mysteries that allow doing so at much MUCH lower cost.

Take the example in the book: enchanting a stone tower with The Perfected Tower. This costs... 196 pawns. It requires 7 seasons to open all of the compound devices and some number of seasons (based on lab totals) probably around 6-7 but potentially much lower to enchant all of the component pieces [another 28 pawns] , which are then placed in the assigned niches. Then you need to know (so, need to invent if this is your first project?) a Bind the Mystical Tower ritual of at least level 44 and make several assorted rolls to finish enchanting the tower with one effect. That's a minimum 14 seasons and a whopping 200+ for one effect.

Or, enchant a small stone that casts The Perfected Tower at momentary duration once per day. This requires 1 season of work and 3 pawns. 224 pawns and 14 seasons or... 3 pawns over one season. That's actually a really bad example for them to have picked, you could be more generous and assume that the effect in question requires an invested item to cast with a structure target... and you'd still never come out ahead with hermetic architecture. I haven't been able to devise an effect that hermetic architecture could do better than the regular method, EVEN if it cost the same instead of magnitudes greater.

As far as I can tell the only thing hermetic architecture as written brings to the table unlock aura guidelines and those are functionally useless due to the problems highlighted above. The common handwaves like "well, use a vis reducing mechanic like the Verditius mystery" don't fix this issue: That same Verditius can make it cheaper, but it still won't be as cheap and effective as enchanting the normal way with the Verditius mystery.

So what's up with this? Am I missing something major? I do not think I am, but it's always a possibility. Without a pretty major house rule rework of this virtue it seems like a massive undertaking for utterly underwhelming results.

I will have to look it up, but I would swear that it does things that you normally can't do with Hermetic Magic, like "+7 to detect lies". Sort of like "Items of Quality", but for a building. A semi magic bonus?

It doesn't.

I didn't want to print the full text of the rules, but all it does is let you enchant large structures for extreme cost. I can't tell how this is functionally useful as you can enchant items that create the same practical effects for fractions of the cost and effort.

So I guess the question is why? Why enchant a structure instead of just casting structure target spells on them for a twentieth or less of the cost and effort?

Hermetic Architecture allows you to upgrade your lab to have a higher Aura, and increase the size of Regios. For powerful covenants, this could be valuable. With great effort, you could create an area that can hold the most magical creatures without acclimation.

I have to guess that whoever wrote the Hermetic Architecture virtue interpreted the enchanting rules far more conservatively than does the current majority opinion on these boards. I agree there's no use for HA on structures if one can just enchant a stone with a touch range effect to do the same thing.

Using the new guidelines for that spell, however, requires Hermetic Architecture as they are only usable with that virtue. Other spells, as you note, could be devised using other guidelines at less vis cost.

Okay, so basically the thing of value you ostensibly get from the virtue are the new aura guidelines. How... useful are they? Looks like not useful.. at all.

Leaving aside for now the exorbitant vis cost, you'd need a Lab Total of over 100 to raise an aura of 5 to 6. Realistically unless you had a lab total a fair bit over 100 (say 120 or so) it just isn't feasible. You'd need a highly specialized labrat to make this kind of thing possible (or even a team of lab rats working together). It's certainly possible but the real question is again why?

You're working to reach a really high lab total to get... +1 aura up to 6. You're giving your lab a plus one to lab totals, a return on your effort of less than 1% on your effort, as you'll need to have well over 100 lab totals already. That's not even getting into how much it would cost in pawns of vis, as examined before.

Changing aura/regio size is clearly far more in the realm of possibility, but again I'm not really clear on why you'd actually want to bother, especially as it still has the awesome sticker price. There are pretty clear indications that story events and other types of effort can increase or expand auras (or even generate auras where none existed) without the direct intervention of Hermetic Magic anyways.

Yeah, this virtue and its effects sound cool and impressive, but when you actually examine it at all the entire virtue just falls apart. Of note, the one canonical example of a massive enchanted structure is in Legends of Hermes and [spoiler]its creator specifically did NOT use hermetic architecture as building a village sized lab proved easier and more effective![/spoiler]

I'd be really interested to hear from anyone who had a saga that used this virtue in practice, otherwise I'm pretty convinced it's an artifact of rules being created that sound cool without making sure they work in practice. Even if it wasn't so insanely expensive to use HA, unless it's actually cheaper and easier than just enchanting an item with a T:structure or T:boundary (through spirit magic virtues) what's the point - it doesn't really hook into the other Arithmetic Magic virtues at all anyways.

I'm going to look at writing alternate rules for this virtue, though it may be slow due to the Christmas holiday. My first inclination is to split the aura guidelines into a separate virtue and the base architecture technique. Or frankly just remove the aura strengthening rules entirely, they're of extremely marginal utility. Pretty clearly, making it so that you don't need to multiply your work and vis expenditures by factors approaching 10 is a great first step - though it again would still just be more efficient and sensible to use T: structure etc. I figure that letting it be an alternate way to use magic to cast ritual spells without capturing and destroying spirits would be a decent niche, at least for targeting boundaries. Thoughts? Will need to think on it more, will have more time to do so later.

Yes, there are other ways to do so spread over the Ars Magica books, but TMK the TMRE p.100 box New Aura Magic Guidelines remain the most powerful and encompassing.

Major modifications of existing, important magic auras and regios are likely the big construction projects of the Order: each will involve several expert magi, but the Hermetic Architect will lead them. Contrary to most Mystery Cults, the members of the Fraternity of Samos "openly and proudly admit their membership" (TMRE p.126), and can be approached if their expertise in Hermetic Architecture is needed.

The Minor Virtue HoH:TL p.25 Tenens Occultorum describes a role in House Bonisagus. The Minor Virtue Hermetic Architecture, together with excellent Vim and decent Techniques, provides a role in the Order. Both mean added respect for the magus, and added responsibility in situations charged with higher-powered Hermetic adventure.

Cheers and happy holidays

Yes, my character is a member of the Fraternity of Samos, I'm fully aware of that mystery path, hence my noticing hermetic architecture. Being a research Bonisagus, he actually wants his lab to be in an area of less aura as he's aware that the benefits of being in an aura to his lab total are minor and the downsides are potentially large with regards to Warping and Twilight in the long run.

The entire point is that "major" assertion. The modifications aren't major. The big sticker item is exceedingly minor in fact! +1 aura is measly! Hermetic architecture is NOT the most powerful method either! It's the weakest and most difficult of all methods! It says it does all of those things but it does not in practice due to the actual rules. Go find a dragon and convince it to live at your covenant, this is suitably impressive and difficult, and it probably will increase your covenant's aura! The RoP rules even reference that HA is difficult for the same result, but "reliable".

You mean Colentes Arcanorum? The purpose of the Tenens Occultorum is to protect the secrets of the Order, not to organize big projects, that's more in the province of the Colentes, who collate magical texts already. There's also no RAW way that enchanting such a large structure would add to a Bonisagus mage's Bonisagus Acclaim. Acclaim is increased through the writing and publishing of books, not of enchanting objects. The aura raising guidelines are not for spells, they are for Mystery Enchantments that would be gibberish to anyone without the mystery. As such it makes much more sense for a Verditius to be motivated to make a truely huge enchantment - and in fact HA possibly works for them, because they can lower its truely earth shattering vis costs to more reasonable levels - though they still need to spend inordinate amounts of time for generally piddling benefit.

At the point where you have ultra-specialized, very high intelligence, Magic Theory, and Leadership magi who has a team of people willing and able to work in their sanctum you've got... a million more powerful things to do that are easier AND have more impact than +1 aura - and such a powerful magus probably would be fully aware of that fact. Part and parcel of the Bonisagus concept is research. That same ultra-vim team is so much better spent put to use as a research task force for expanding hermetic theory regarding auras, something they're more likely to be motivated to do, and something that will have so much more impact - and they know it. At the levels of difficulty we're talking, a breakthrough is not out of the question.

We did some math with our magi at projected two years past gauntlet and figured that for a minor breakthrough we're all motivated to learn (few and far between for story reasons) we could smash out an ancient magic style integration in a few short years if we bent the resources of our covenant to it: Companions and a magi traipsing off to explore and get insight sources, one magi who is good (IC and mechanically) at hermetic insight pumping out insight lab texts, other magi spending seasons to create the resultant effects. A curveball such as an effect that takes longer for us to create or a lack of Insight materials would slow us down... but would not reasonably slow down the oft-posited covenant of super Creo Vim specialists with lab totals reaching 120-150. That covenant should probably be integrating magic left and right using the same kind of structure I just described: one or two magi processing Insight to create Insight Lab texts (spending time to translate them as they go, or just using agreed upon abbreviations for this one purpose), that same team required for HA to generate effects and pool their breakthrough points.

Is any of that analysis wrong? I have read the ArM5 catalogue. I fully understand how it works (I think). I get that it's supposed to be this big crowning achievement of ultra-powerful magi, and that there are rules for teamwork and ways for a powerful magi to collect lab rats. The problem is just that it's way too expensive and difficult for what you get - at that power level enchanting a building is a anticlimax, even if you're enchanting it with +1 aura.

Bringing HA down to earth, pulling it back from beyond the lunar sphere so to speak, would make it a reasonable virtue for a reasonable covenant to use instead of a mystifying, pointless capstone project for a theoretical ultra-covenant. The aura upgrading feature is a weird first-attempt at the rules in RoP:M and need significant reworking, and seem very tacked on in Arithmetic Magic, which is itself kinda jumbled.

EDIT: The thread title is probably confusing. I know mechanically what it does, and what it says it's for. I don't understand why any magus, nevermind any player, would actually bother given the mechanics. What is it practically for? So far the answers here seem to be "nothing".

It was also, afaik, the first method published for increasing Auras in AM5. Ars Magica isn't immune to the power creep issue most long running gamelines suffer from.

TMRE is essentially a revision of the 4th edition Mysteries book. That book took a lot of criticism for excessively powerful and unworkable effects. TMRE did a good job of bringing mystery powers back down to earth but went too far in a number of cases, such as Vulgar Alchemy. Hermetic Architecture is another example of this, imo. When I first read the rules for this virtue I thought it allowed enchantment of boundaries using the multiple devices trick but, sadly, this doesn't seem to be the case. If you house rule to allow this the virtue becomes more reasonable.

That's really useful context, thank you! I've not read the original version of the book.

The 4th edition one allowed you to enchant virtues in a room (at moderate cost) or structure (at double the room cost), so you could build a library where everyone was a better author or book learner, or a hospital where everyone was more resilient, or just about anything. By letting you have places where people benefited from a virtue, it was a mystery that allowed you access to something Hermetic Magic is normally terrible at - granting Virtues.

As it stands, Hermetic Architecture is for allowing you to create or destroy connections between levels of regiones, which may be useful if your covenant is situated in one or near a multi-level one. It is one way of allowing you to enchant boundaries, but I'm not sure how many different ways there are of doing this and which ones are the most effective.

There's potential there to develop a Major version of Hermetic Architecture that allows such effects, and/or aura tempering as per RoP:M's aligned auras. It's a good player research project or alternately a deeper secret of a mystery cult.

The boundary part is ambiguous. Boundary effects may be enchanted

But the text makes it sound as if the "actual structure" has to be an architectural construct, albeit of possibly enormous size.

The virtue is much more useful if it extends to arbitrary boundaries, so that one can, say, enchant an entire magic forest with enough effort. I would house rule to allow this even if the RAW doesn't.

Aside from this, the effect level and associated vis cost is excessive. The example in the text requires seven identical devices to effect a stone tower of Structure size. I think most players these days would allow a Structure to be effected by a single device, under core rules alone. Still the virtue has potential.

Something occurred to me. In the RAW you can have a team of people enchanting your HA pieces for you, in theory dividing that part of the work. However, the few unique guidelines that HA adds (which, as has been determined is the only thing this virtue gets you) are mystery enchantments and therefore you would need a team of people all with Hermetic Architecture to replicate them, even from one ultra-mage's lab text. Oops!

Okay, I've read the 4e rules now. Hermetic Architecture takes the virtue in a totally different direction than Sacred Architecture, but then tries to circle back around and do some of the same stuff. It's entirely not clear what the actual use is intended to be, and the rules are pretty tortured compared to "decide on an effect and build a building by accumulating points"

I've got to work on numbers/formulae, but I'd just:
Make the base method dramatically easier and cheaper and make changes to effects.
Split the target point cost among items instead of multiplying across items.
Clarify the rules on Bind the Mystic Structure
Rework guidelines, still limiting the new guidelines to use ONLY with HA - but not requiring N copies of the same enchantment.
Remove the aura boosting effect entirely, it's overpriced and useless.
Add guidelines for aligning auras (as in RoP:M)
Add guidelines for tinting auras (as in RoP:F)
Add guidelines for manipulating aura tethers (as in RoP:M)

I like the idea personally of instilling virtues, but it seems like that would be something for a breakthrough - potentially not a very huge one if you already know the entire string of arithmetic magic. Aligning and tinting auras is frankly close enough to most simple virtues that might add a few points here or there to specific activities that it may be unneeded.

Likewise, I really like the 4e's design flow for this virtue: Design an effect as a function of a structure, build said structure, the structure slowly shapes the aura its in based on how well you build it. I don't know that it's really worth reinventing the wheel entirely to bring that forwards as part of the base mechanics, but it could be included in the guidelines for aligning/tinting/tethering auras, as described in RoP:M - basically providing overriding modifiers to the aura fluctuation rules, but coming into effect at the same pace as those.

Yeah, do something like this. The Mystery as it stands is, IMO, a bit useless.

I really like the Virtue thing from 4e. And I like the flavor of enchanting huge structures, but I don't really see it gel well.

Here are some thoughts towards making 5e Hermetic Architecture more useful without changing the basic character of the mystery.

  1. HA effects only require multiple devices if the target is Boundary. Rooms and Structures may be affected by single devices, with size modifiers to level if needed, as per the core rules.

  2. The rules for multiple devices can be used to enchant Boundary targets. While this may seem a bit beyond "architecture", it allows for such larges effects as the purported Masonic Washington D.C. layout and seems within the spirit of the virtue.

  3. If multiple devices are used, the effects in each device may use T:Individual rather than T:Boundary. This reduces the vis cost to a somewhat more moderate level.

In this case (wanting to enchant a room or structure) what would HA do then, as you can already enchant a room or structure with a single device? I guess let you raise the aura in just one building, but that circles back to the discussion on the massive difficulty as presented in the book of increasing auras meaningfully. You could realistically add an aura point or two to a mundane area as a big project with reasonable returns, but not raise the aura in a reasonable covenant without rather extreme and unreasonable wasted effort.

Agreed: It sort of implies half of the time that you can enchant boundary targets and then implies elsewhere that you can't. Just clarifying that rules fixes a sort of high-concept issue with the virtue, but doesn't touch any of the detailed mechanics problems.

Actually it barely dents the cost at all: The dramatic majority of the vis cost involved with the RAW is in opening the component items, not with instilling the effects. As the rules are written, the floor for instilling effects is T: Group, reducing the effect from T:Boundary down to T: Individual would at best save 4 magnitudes of effect, that's 2 pawns saved on each device. You'd still need to open enchanted items with a number of pawns equal to the size x material of the target structure/boundary times the size modifier of the structure/boundary again. That's by far and away the huge cost - and doing the special big thing the virtue brings still isn't anywhere near worth the effort for anyone to actually do.

Consider an Enchanted Cornerstone of the Wizard's Tower to increase the level of the aura within the tower by +1 to a maximum of +5.

Base 55. Range:Touch (+1M) Target: Structure (+3M) Duration: Sun/Perm (+2M, +4L). Final Effect Level 89
Especially large towers or a covenant built as a single large structure can be affected with +1 (or more) magnitude size modifiers.

Since there's only one device, no ritual of binding is required. I would require each structure to have a unique enchantment devised for it, so that the cornerstone can't be moved to provide mobile auras. This is fitting with the concept of architecture. Overall the cost and effect seem within the bounds of reason, certainly much more than an effect built with the multiple devices rule.

That's a good point. I'd neglected to consider the chart in TMRE on opening the devices. I'd allow them to be opened according to the normal rules for invested devices, requiring vis appropriate to hold the actual effects.

<Dusts off copy of The Mysteries>

Hermetic Architecture is the only way to enchant a room that is not your lab, or avoid constructing a lab outside the building you wish to enchant. I agree that the costs for a tower are ridiculous. How's this for a suggestion:

Using the example of the Perfected Tower, how much vis to enchant a Size 7 tower? With the requirement of having to make a very high level Bind the Mystical structure, I'd think that you should be able to make the components as either lesser enchanted devices or fully invested items, as you need them. The invested components don't need to have duration amplification - the Bind spell incorporates all of the components that are geometrically tied. Range is Personal, to affect the building itself, or Touch, to affect inhabitants. If Penetration is desired, it must be identical on each component. So this conception has 2 X 7 = 14 + 12 = 26 vis required. If one's lab total is high enough, it's possible to make more than one component per season. This rule requires one invested component per point of size, and its cost is dependent on the complexity of the effect.

If you want more than one effect on the building, then you must make them as full invested items (Lab texts help). For two level 20 effects to be created, each component needs 8 vis (4 vis to open, then two vis each for the effects). We are looking at 8 X 7 = 56 + 12 = 68 vis. I would also rule, that as a Mystery, it is outside of Hermetic Theory, and thus, does not cause warping. This added benefit may make the cost more tolerable.

The person creating invested components doesn't need to have the Mystery, only the magus casting Bind the Mystical Structure does. He must be involved in the design and calculate the proper placement of the components. After the components are constructed and installed, he can bind the enchantment together.

This still requires the Hermetic Architect to be an expert at ReVi spells. A level 60 effect is needed for just about anything.
<Edit: clarified components>

You wouldn't do that in - say - Durenmar or Fengheld, would you?


I didn't say, that Tenentes Occultorum organized big projects, but that they perform a role in their House. An important one indeed, i might add, which should lead to occasional adventures. AFAICS this is also the purpose of 5th edition Hermetic Architecture.

Hermetic Architecture might indeed rather appeal to Verditii. And The Mystic Fraternity of Samos is

A Bonisagus has taken the oath

So the player of a Bonisagus needs to determine with the SG at least, why his magus didn't "find" the teachings of his Mystery Cult and can hence keep them a secret. And once this is settled, he needs to have a reason for learning secrets from his Mystery Cult instead of furthering the knowledge of all the Order by direct research.

This would be judged by the magi commissioning the effect. If the aura is important enough to them - due to it's specific properties, or because it is an important regio level or the aura of their covenant - they might put up the vis. The team likely wouldn't work all in the Hermetic Architect's sanctum and lab, but each important member in its own: see e. g. TMRE p.98 box Seasonal Vis Limits and Very Large Structures.
Such undertakings are indeed 'archmage level', and the purpose and intention of archmages are typically not completely rational.