Why do wizards love towers so much?

Games Discussion Ars Magica
21

I would be interested in that spreadsheet.

Also, completely agree with you on the reading (or ruling) that adding size magnitudes to Aegis does not require a breakthrough. Boundary always seemed much larger to me and I was kind of shocked recently when it was pointed out to only be 100 paces... sure, a 100 paces diameter is fairly large by many measures, vs the footprint of a tower made by Conjuring the Mystical Tower for instance, but 100 paces is much smaller than many naturally occurring boundaries.

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22

The last paragraph of Aegis of the Hearth lists it as a Major Breakthrough and altering the parameters would require a similar Breakthrough.

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The last paragraph of Aegis of the Hearth lists it as a Major Breakthrough and altering the parameters would require a similar Breakthrough.

What's not clear is whether adding size magnitudes counts as altering the RDT parameters. My troupe always assumed it does not, and that T:Ind +10 size is still T:Ind (which also means you can't e.g. use Flexible Formulaic Magic to boost T:Ind to T:Ind +1 size).

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I will see if I can get the spreadsheet typed up when I get home from work today.

I too was shocked at the small size of a boundary target. In my mind boundary always meant "whatever can be reasonably described as my land", as opposed to a circle 100 paces in diameter. When it has come up in discussion of the Aegis among my group and a previous group too, we all seemed to agree that the size of the boundary depended on how well establised a claim the magi had to the area of the boundary, essentially meaning that older more well established covenants could cast the same Aegis over larger areas. This interpretation gave us a good reason to go out and mystically mark the land with standing stones, statues, mystically significant trees etc. because they all contributed to the mystical connection between the magi and the land that our interpretation of the Aegis used/uses.
IMS we have it follow the actual borders (walls) of the castle our magi inhabit since that is the boundary of our covenant. If we were Durenmar though I would have had it cover all three outlying villages too (but require added levels for magnitudes of effect).

Thats a very interesting use of Flexible Formulaic Magic that I had not considered but that I would also 100% allow in my own saga. Glad that you mentioned it so that I am not potentially taken by surprise by it in the future.

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25

My troupe has always read size as a "hidden" RDT(S) parameter, since it is mandatory to affect some individual targets like large (+2) humans and creatures. FFM has been used to affect those repeatedly. It doesn't break anything.

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26

I doubt the authors reviewed the Aegis when they introduced size as a parameter in 5ed (or was it 4ed). The text has not changed, I think, since 3ed. Not sure about flexible magic, would not be surprised if that has stuck around unchanged too, or maybe was authored before the size concept was.

The way the Aegis is narratively described, with the big procession encircling the entire covenant grounds, it is very hard to imagine that they are universally restricted to 100 paces diameter. Therefore there should be 1000 pace versions available in the order.

While the size rule is a good idea which makes the spells both more balanced and easier to design fairly, it requires a new review of all the spell descriptions and guidelines, and it does not look as if that happened.

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27

I have typed the spreadsheet up now and I feel sure that I know what writing up a lab text feels like for a magus now! There were a lot of personal shorthands in my original document.

Feel free to comment if you find anything you dont understand or if you find a mistake. Feel free to download, use and repurpose the sheet too. There's really no reason why the tower has to be a single structure. You could just as well conjure a structure made up of various shapes merged together.

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Nice. I have always assumed that 1 pace is 1 meter and that it is equivalent to 3 feet. Not exact, but makes conversion between systems much easier. it looks great. Thanks. I have always assumed that the tower has 20 feet of CELLAR space not just a chun of stone acting as a foundation, so we have always put stuff in the 20 feet below ground. But your calculation is probably more accurate in how the spell reads.

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I have also always played where below ground it is usable floor(s).

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There is a canon instruction to «think of» one pace as one yard (=3') (and equating 1 yard = 1 metre is a 10% error which is not narratively significant). Letting one pace be ¾ metre deviates more from canon, but is better in line with the Roman measurement.

Anyway, I am not convinced that it is only the volume of stone which should matter in size calculation. I think the inclusion of the internal (empty) space in the calculation is deliberate. Is it ambiguous in the rules, or have I misread?

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31

Whether this is "right" or not, dunno, but I think Internal space is not included due to a long chapter of a book (Hermetic Projects) being all about creating huge, circular walls in the ocean then filling them in with sand, dirt, clay, etc.

Side note: Hermetic Projects seems to completely ignore the displacement of water that would happen when you fill in the area using Terram.

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32

the length of the pace has puzzled me a lot. Because I remembered thinking it was 1 meter in canon but then I looked it up and according to google it is 75 cm. But now that you have mentioned it and stirred up my memory I am sure you are right that en ArM5 pace = 1 yard. Which gives us probably twice the amount of stone to play with.

I think the spell in the core book is pretty clear that the space below ground is not a cellar, as it specifically mentions a foundation. Also note that there is no requisite for the displacement of the ground that surely must happen to accommodate the newly conjured foundation. which coincidentally could be why the author of Hermetic Projects decided that displacement is apparently not a thing in ars magica. However If the foundation can displace the earth then why not displace a whole floor into the earth with it and get a cellar that way? Also if you conjure the tower in a place where a natural foundation is provided I see no reason why the foundation couldnt become a cellar or be left out for the material to be put to better use. I really see a lot of value in inventing alternate versions of this spell tailored to the specific location that the players find themselves in.

The reason why I included the option to make the foundation deeper in my calculator is because I foresee situations where a troupe might argue that a bigger tower needs a deeper foundation in order to not tip over due to displacement of soft soils underneath.

The reason why I did not include internal space is because I think that the +3 magnitudes for elaborate design should be enough to make the conjured stone wrap around itself. I also dont think it is a very straightforward interpretation that the "stone allowance" is spent on the air inside the tower as well. But that said I do also think that Hermetic Projects backs up my interpretation.

There are also a lot of potential repercussions to casting the spell already so I think it is fair that the tower can be pretty big. The towers in Durenmar are supposedly conjured by this spell and they would be pretty underwhelming if they followed the canon. Each floor in the canonical tower only barely has room for a hermetic laboratory and then only if you make the walls thin and/or dont include a staircase. I would also argue that casting the spell is pretty expensive in mundane money as you still need to outfit the tower with things like windows, furniture, doors, you need to add hinges for the door, which means you need to make the doorholes wide and then later on have a mason do brickwork to mason in the hinges. There is probably a lot of other woodworking to do, in many cases it would also be more attractive to conjure a tower with no floors but lots of holes/arms for beams and then make wooden floors.

33

I’m not an architect or engineer but I’m pretty sure foundations can be somewhat hollow but where I got that it had basements is from the description of the Library at Durenmar, GotF p52:

“ It was created by the first ever cast-ing of the ritual spell Conjuring the Mystic Tower by the Founder Bonisagus himself. The success of this spell set the template for the other two towers at Durenmar, created decades later by his successors, and numerous others in covenants throughout Europe. The tower is perfect-ly round, 80 feet high, and 30 feet across, with seven floors above ground and two basement levels.”

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34

I’d also point out that the weight of the stone is what affects size in the spell sense, not size as in space including the air. The perfect stone created by creo being of amazingly uniform density does allow the area of stone to map easily to cubic paces (or whatever measure you're using).

From ArM5, p113: “ This depends on the mass of the target, so a five level boost to a Corpus spell would allow the magus to affect a giant up to fifteen feet tall, not sixty feet tall.”

[sorry, don’t seem to be arguing with anyone anymore but remembered. This and felt it relevant and could not resist adding it.]

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35

Rather inconsistent, though, to give base size definitions by volume and increments by mass ...

Well, well, it is not the only inconsistency in RAW.

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I disagree. The quote you mention is immediately after a sentence about the increases in the size of the target. The complete relevant text from ArM5 p.113 is:

However, the size of the target does make a difference to the level of the spell, with the sole exception of Intellego magic. Every Form has a base size for Individual targets, and targets of that size or less can be affected by a spell of the basic level. Adding one magnitude (five levels) to the spell multiplies the maximum size of its target by ten. This depends on the mass of the target, so a
five level boost to a Corpus spell would allow the magus to affect a giant up to fifteen
feet tall, not sixty feet tall.

The relevant factor for a spell is size, not mass. Mass only comes into it when you are boosting the size of the target, as a way to specify that 10 times is not for a single dimention (height in the example), but for all three, thus mass for a solid.

Let's take a look at the base individuals for each Form:

  • Animal: An animal of Size +1 or lower. HoH:MC p.39 let us know that birds are 1 Size point bigger than their weight would suggest. This doesn't mean that a base individual could be a Size +2 bird because its mass is lower.
  • Aquam: Use a volume of different liquids (water, natural liquids, processed liquids, corrosive and dangerous liquids) and poinsons which are a single dose no matter its volume.
  • Auram: A single phenomenon, most of which have little mass (cloud, wind, bolt of lightning), although they have a defined volume (equivalent to a Boundary).
  • Corpus: An individual of Size +1 or lower.
  • Herbam: A plant roughly one pace is each direction. I have often seen people say that this means a T:Ind Creo spell can conjure a mass equal to a cubic pace of solid wood, but to me that is abuse plain and simple. A plant of that size may weight about 20 pounds. Many magnitudes from the several tons that one cubic pace of wood weights. And that base individual should be in a naturally occuring shape (a living plant, a fallen branch, etc.) because you otherwise need to add a magnitude for plant product (cut timber).
  • Ignem: A large campfire or the fire of the hearth of a great hall. Again, fire has little mass, so this seems based on volume, perhaps a bit larger than 1 cubic pace.
  • Imaginem: The equivalent of a human being (size for an image, volume for noise). No mass involved again.
  • Mentem: Minds do not have size.
  • Terram: Described as a volume of various stuff (sand/dirt/mud/clay, stone, base metals, precious metals, gemstones).

What I see emerging from that picture is that, for those Forms where base individual is relevant, it is based on volume. Sure, for solid objects that often mean a corresponding mass, but only indirectly.

A tower is a discrete object made of stone. A base individual-sized tower would be about 1 cubic pace in size. That is why Conjuring the Mystic Tower has 4 magnitudes added for 10,000 increase of size (its actual volume is about 2,500 cubic paces).

If the increase in size of a base individual was based on mass alone, the spell would need only 3 added magnitudes, as certainly more than 60% of the tower is empty space.

Yes, the spell's design is sub-optimal and the tower could have been about 4 times the volume. Such as a square tower 45 feet by 45 feet, 100 feet high with a foundation 30 deep. But Conjuring the Mystic Tower is a legacy spell, so my guess is that the 5th edition designers preferred to keep the dimensions of the tower the same as in previous editions. It's easy to say that the magus who originally designed it used a different set of constraints and desires when the spell was first invented.

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37

Underground locations can make good use of vertical space and best use of an aura.

Who loves underground locations? People following Dave Arneson's lead and wanting a roleplaying area where choice of movement is restricted to a small map.

In the real world, underground locations are favoured by people trying to hide away, and are cramped. People with money and power prefer the visible architecture.

Now, if in your world attacks by flying creatures such as dragons are common, a tower is a risky business and you'd be better off underground. Luckily for the inhabitants of medieval England, their chronicles only record a couple of hundred dragon sightings a century - Ars auther CJ Romer worked worked out that on average it worked out as one dragon per county per decade.

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38

Dragons aren't all 60 feet long with big bodies. They come in many sizes and shapes, some of which are more serpent than anything else. Building underground isn't a great defense and gives you lousy offensive potential versus any dragon. At least a solid stone tower offers lots of lines of sight for magi to exploit and won't burn or break easily (though some of the contents might).

But you're right in that living underground mostly sucks and most people won't want to do it. If that's where your Aura is you gotta suck it up, but otherwise most people will build above ground.

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39

the length of the pace has puzzled me a lot. Because I remembered thinking it was 1 meter in canon but then I looked it up and according to google it is 75 cm. But now that you have mentioned it and stirred up my memory I am sure you are right that en ArM5 pace = 1 yard.

Ars Magica treats it as yard because a yard is familiar to ... well, the rpg community, which somehow seems based around the US, UK etc. and seems to involve a majority of gamers with Lesser Immunity: The Metric System :slight_smile:
Technically, a Roman pace was a "double pace" (the distance between consecutive footprints from the same foot of a marching legionaire), and thus roughly 1.5=0.75x2 meters. And a Roman mile (literally "a thousand") was indeed ... a thousand paces! We use this as a the standard pace in our games, because it feels "properly Mercurian":slight_smile: Then again, I remember a short game where the pace was literally defined as the caster's pace, in the same spirit as R:Voice, which increased the impact of Virtues and Flaws such as Large or Dwarf on magus PCs.

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40

I will add a recalculation based on the yard-pace perhaps this morning, perhaps after work.

As pointed out above the base individual in size is given in mass rather than height, which is pretty reasonable. However for most substances the mass and the volume is proportional which means that we can be certain that if a base individual for stone (Terram) is one cubic pace, then 10000 times base individuals will be 10000 cubic paces. You would get the same result if you broke out your calculater, looked up the density of stone and converted 1 cubic pace into kg's and multiplied that number by 10000 and divided by the density again to get a volume.

Interesting and not entirely unArM idea to have base measures be measured from the magus' body. I would not want to implement it thought because the issue rarely comes up and it would also punish people for not making their character as tall as the size limit allows.

As for living underground, I would not do it unless aided by significant magic as underground spaces are always humid and dark and mostly cold. Natural caves for example always have 100% humidity as soon as you get away from the entrance and this happens because they are enclosed spaces underground. Sunlight is also rather nice and I would not want to do without it.