Pinning down Weaving for more consistent rulings

[galivet]

For me, the RAW constraints on Weaving spells are too vague. I believe that there are some implied restrictions or other heuristics in play when determining whether a Weaving spells is valid, and I would like your opinions on those.

Here are the explicitly-stated restrictions:

1. The spell modifies nearly any property of the target.
2. The spell must not transform the target into something completely different.

Left unstated is whether the Arcanum of the spell must govern the modified property, the nature of the modification to the property, the target itself, or some combination(s) of those. Also left open to interpretation is what qualifies as a "completely different." I suppose these are two points for which I would like some additional heuristics.

I feel the ambiguity opens me up to making inconsistent and even biased rulings during game play.

[Tessie]

Left unstated is whether the Arcanum of the spell must govern the modified property, the nature of the modification to the property,

If these can't be attributed to the same Arcanum, you're probably transforming the property rather than modifying it, making it a Patterning spell.

But if you do modify a quality in a way where the chosen Arcanum doesn't govern both of these, you need to add another Arcanum. For example, State Change changes the property of the subject's state of matter, but one of the four fundamental states does not fall under Matter so you need to add Forces to change the subject's state to plasma.

the target itself,

The target should only be needed to be governed by the Arcanum if the nature of the target is the focus of the spell, which, again, would probably make it a Patterning spell rather than Weaving. Unfortunately there are tons of exceptions, generally involving Forces, Life and/or Matter.

Also left open to interpretation is what qualifies as a "completely different." I suppose these are two points for which I would like some additional heuristics.

I feel the ambiguity opens me up to making inconsistent and even biased rulings during game play.

The best way seems to be to just familiarise yourself with the published spells to get a feeling for it. Personally I tend to think of Weaving as "modification" and Patterning as "transformation" and work from there, but that does not follow the published spells as closely as I'd like.

[galivet]

I'll also say that "property" itself is ambiguous.

"Elevation above sea level" is a property that everything has, even spaces. Modifying that directly seems ludicrous, but why? There is some heuristic in play there that I can't articulate.

[galivet]

EDIT: Never mind, I misread.

[Tessie]

I'll also say that "property" itself is ambiguous.

"Elevation above sea level" is a property that everything has, even spaces. Modifying that directly seems ludicrous, but why? There is some heuristic in play there that I can't articulate.

It may seem ludicrous, but honestly I would allow it as a Space Weaving spell. It's not dissimilar from Ban.
Edit: But do note that "elevation above sea level" is an arbitrary measurement and not a proper quality. The spell would instead change the distance between two points within an AoE. For elevation, the points would be the sea level somewhere below ground, and the ground, but it's probably much more effective between two horizontal points where the practical effect would be similar to Ground-Eater.

[galivet]

How about physical properties like mass and density in the context of Matter and Life?

Possibly there are some properties that don't fall under any specific Arcanum and in those cases you consider only the appropriate Arcanum for the target?

[galivet]

It may seem ludicrous, but honestly I would allow it as a Space Weaving spell. It's not dissimilar from Ban.
Edit: But do note that "elevation above sea level" is an arbitrary measurement and not a proper quality. The spell would instead change the distance between two points within an AoE. For elevation, the points would be the sea level somewhere below ground, and the ground, but it's probably much more effective between two horizontal points where the practical effect would be similar to Ground-Eater.

Yeah, if "elevation" is considered a property of an object for which Weaving can modify the value, then we may as well say that "position" overall works the same way so we can accomplish teleportation with Weaving. Obviously that's somehow untrue since Teleportation is a Patterning spell, but I can't explain why. The restriction on Weaving is that the target can't be completely transformed. Teleportation doesn't completely transform the target; it modifies the target's location property. Or, if I'm misunderstanding that, it's not clear how "location" is not valid as the property of a subject of a spell.

So it's unclear to me how to know what things we commonly think of as "properties" are actually something more fundamental that requires Patterning to change.

After reviewing the published spells several times trying to work up my own heuristics, the best I came up with is balance concerns: some spells arbitrarily require higher practices, mana, etc... just because they're particularly useful and since that's a subjective call you can't apply consistent judgement about it for Creative Thaumaturgy. It's like holdover 1e thinking.

[Mrmdubois]

Mass and density both seem like properties you could alter relatively easily at 3 dots.

Something that might be helpful to keep in mind is that Weaving happens at the same point as getting Perfecting and Fraying. If you could Perfect or Fray a part of your subject, then you can also Weave it into something else.

[proindrakenzol]

I'll also say that "property" itself is ambiguous.

"Elevation above sea level" is a property that everything has, even spaces. Modifying that directly seems ludicrous, but why? There is some heuristic in play there that I can't articulate.

Changing something's location entirely is considered a transformation, see Teleportation. Slightly stretching space is Space 1, see Ground Eater. Giving a location the effects of radically increased elevation (i.e. a thinner atmosphere) would be Space 3 and would probably be an Extreme Environment of 2.

[galivet]

Mass and density both seem like properties you could alter relatively easily at 3 dots.

Something that might be helpful to keep in mind is that Weaving happens at the same point as getting Perfecting and Fraying. If you could Perfect or Fray a part of your subject, then you can also Weave it into something else.

My question was more about which Arcanum to use for which type of subject. Maybe someone thinks of mass and density as concerns of Matter (a physics background biases one to this perspective), and so (by the above logic we've been discussing) Matter can modify those properties in any kind of subject. Or maybe mass and density don't belong to any one Arcanum in particular and so you need to use the appropriate Gross Arcanum for the subject.

Basically, would you allow a Matter Weaving spell that made a person less dense (e.g. to sink into water)? Or would you require Life for that? What then does that say about properties like mass and density? How do we know when a property belongs to a specific Arcanum and when it cross-cuts?

EDIT: This is in the context of Tessie's post above.

[galivet]

Changing something's location entirely is considered a transformation, see Teleportation. Slightly stretching space is Space 1, see Ground Eater.

This is the "give a man a fish" answer. I'm looking for the "teach a man to fish" answer. It's obvious that spells of other Gross Arcana don't consistently follow this same scheme with respect to "changing something's INSERT PROPERTY HERE."

Why is using Matter Weaving to change a subject's state of matter different from using Space Weaving to change its location? I can't reason about Creative Thaumaturgy spells based on "Well it just is."

[Mrmdubois]

The first question to answer when casting a spell is, "What do you want this spell to do?" You always work backward from that. It shouldn't be too hard to get the answer for what arcana to use from the answer to that question. There are guidelines in the magic section on what kinds of effects you can expect each relevant dot level to accomplish, there's a sidebar that talks about how many arcana could be used to achieve the same effect but they might not all be achievable at equivalent dot levels. You can probably also receive some insight on which Practice is being used by asking yourself, or your player, how the spell is doing what it's doing.

Density or weight can be a property of Matter, Life or Forces in a rather obvious way, though there may be more esoteric ways to derive value or makes changes to it from the other arcana. Still, there isn't going to be a perfect one size fits all answer for every scenario. You will have to accept the fact that some of the burden falls on you to figure things out. Which yeah, is inconvenient, but that's what we have. If you have a problem with a decision you've made, either because you think you made a bad call, or because it becomes a table problem when a player thinks they should be able to do something similar to what they or someone else already did but it doesn't quite work...that's when you talk to your table OOC. From there lots of options are available for resolving the issue. Most of the time as you accustom yourself to the system and to the way you want things to work at your table you will find that having an answer to these kinds of questions is a pretty straightforward affair. If that means you think Teleport should be at 3 dots instead of 4, or density is a property governed solely by Matter or whatever, it's fine.

[galivet]

Thanks -- I just wanted to make super sure I wasn't missing some general consensus or ancient 4chan midrash from Dave that provides any extra insight on this.

[proindrakenzol]

This is the "give a man a fish" answer. I'm looking for the "teach a man to fish" answer. It's obvious that spells of other Gross Arcana don't consistently follow this same scheme with respect to "changing something's INSERT PROPERTY HERE."

Why is using Matter Weaving to change a subject's state of matter different from using Space Weaving to change its location? I can't reason about Creative Thaumaturgy spells based on "Well it just is."

When you use a Matter Weaving to change steel from a solid to a liquid you are granting solid steel liquid properties, the steel doesn't actually become real liquid steel because it remains room temperature and liquid steel is not room temperature. Changing solid steel to liquid steel completely would be a Patterning spell.

Similarly, there is a Fraying spell in Space that removes the separation between two places, Co-Location.

[galivet]

I guess I just have the curse of always picking the worst example. That rationale isn't applicable to other Weaving spells in the rule book.

Cold Snap does completely transform the temperature in the area of effect from whatever it had previously to (at least) zero. Turn Momentum does completely change the subject's momentum.