As people have noted off and on, this spell is ... a bit of an oddity.
PeHe 30 / R:Touch / D:Mom / T:Group
Base 3
+1 Touch
+2 Group
+3 size
+1 fancy effect (the spell effectively keeps being cast while the caster walks seven miles)
(As you walk through a forest after casting this spell, all the plant material 10 paces in front of you and 5 paces to either side withers and dies. Trees are reduced to bare trunks, while their leaves and all smaller plants turn to ash. You can walk for 7 miles with each casting of this spell. Use of this spell in faerie woods is not recommended. This spell was originally invented by a magus of House Flambeau, and he was awarded a prize for it by his primus.)
So, it's a "D:Mom" spell that actually lasts for 2-3 hours, as you walk 7 miles (plausibly longer, if the ground is rough & slows you, or you're infirm/slow, etc... it lasts however long you need to walk 7 miles (I'd probably SG-fiat that you debuff at "Sun"))
Is +3 Size actually enough to boost T:Group to a 7-mile-long strip of plants?
+1 magnitude for "fancy effect" SRSLY?
Taking this spell as setting a precedent... the mind kind of reels at similar potential exploits.
Has there been any exploration/explanation/etc? My search (both search-function here on the forum, and Google out on the Wierd Wild Web) has only found people citing it in creating their own oddities.
Heritage spell, like CtMT and Trackless Step. Recommend not even thinking about using it as a precedent spell.
Spells like this are often seriously over or under powered to hit a specific level. This one is over powered. Total target is Base Individual (1 cp) x10 Group, x1,000 Size = 10,000 cubic paces. 10 paces wide by 1 pace high, to reach 7 miles you need 123,200 cubic paces. So it needs at least +1 more Size if you fudge a little.
Duration isn't actually the distance per say. It could be that it destroys that 7 mile strip when you cast it and the 'fancy effect' is it happens as you walk rather than instantly.
Treading the Ashen Path (like Ball of Abysmal Flame, Pilum of Fire, and Incantation of Lightning) appeared in the second edition core rules. These spells are over 35 years old, and absolutely do NOT conform to (nor should ever be used as examplars to interpret nor rule upon) 5e spell structure.
We're stuck with these spells being canon, in all their poorly-written glory, though. I guess the best answer (aside from 'just ignore it and get on with the game') is to treat them as poorly understood edge cases which can form the basis of research into new targets, ranges, durations, or other odd effects.
It's effectively the While Duration, inasmuch as it continues while you keep walking (up to 7 miles). While is equivalent to Concentration, which is... +1 magnitude.
If you want to be a stickler about it, add another +1 magnitude for non-standard Duration. But it is not particularly overpowered.
Strike the guidelines down with all your hatred and your journey toward the Dark Side will be complete.
Seriously, though, the guidelines and R/D/T numbers are best thought of as a combination of convenient building blocks and safety rails. Makes it easy to assemble spells, and if you follow them you can't go too-far wrong.
OTOH, if you follow them too strictly you miss out on cool stuff like, well, like Treading the Ashen Path. The best spells, IMthishisthehillI'lldieonO, have some twist to them that expresses the sympathetic/contagion/mythical twist in our minds that makes us think that the universe should work the way we want it to, and at our convenience. Something that expresses the heart of magic.*
Back in 2nd edition spells were built by real mages. They didn't have books full of rules, or need them. They raised their arms, wiggled their fingers, and chanted "Um ... how about 20th level? Don't everybody look at me like that. 30th?"
It was glorious.
By all means, take the spell as a precedent. But don't try to reverse engineer it into a set of questionable guidelines or R/D/T numbers. Instead, use it as an example of a unique, interesting and fun - if you're a Flambeau, I guess - formulaic spell, and come up with your own unique, interesting, fun spells.
*Hmm... I was going to link to what I thought was a really interesting paper on how the Sovereign Citizen movement is very, very much like a belief in magic. (And perhaps a Mystery Cult, come to think of it.) But, searching for the paper, I couldn't find it because, it turns out, that's a pretty common observation.
I would read this as 8% of the volume is filled with plants. An inch thick branch every square foot is... something like 1 / 144. Let's call it way less than 2%. Seems reasonable at first glance.
1 acre is 2.5 tons of hay, that's 43560 sqft for (8x4x4 ft / ton) ~ 320 cuft.
That's 1 cuft per 136 sqft, which looks close enough.
This is the piece of brilliance that a lot of people miss when they see "legacy" spells from earlier editions. There is generally some way to make the spell fit the rules, as the above example shows. One could even argue the fancy effect should be +0 as it weakens the spell. +0 fancy effect (instead of happening immediately, the spell happens as one walks).
The description could have a flavor paragraph. The inventer of this spell, Primadonis of Flambeau was a notorious show off. While this spell could happen immediately, he liked the look of the forest withering with every step he took.
I think it needs the fancy effect magnitude to account for the duration of the walk, seeing as being within 5-10 paces is what defines the plants as being part of the Group Target. You wouldn't have any way to denote a 7 mile long, 10 pace wide strip of plants as a single group otherwise, at least while not affecting any plants outside the strip. I'd say it's a necessary part of the effect.
Thinking about it, I agree.The group would logically be the forest, so the fancy is significantly modifying the spell, and arguably at times only destroying the 10 pace wide strip would be better than destroying the forest, so +1 is justified.
You have to calculate for worst case rather than average or best case.
I used 1 pace high for the rough number, but the spell should hit things up to 5 paces high (to match the 5 paces to each side). That brings the total potential area to 616,000 cubic paces. With stock mags it is good if less than 1.6% of the potential has plant matter in it. Worst case would be higher than that.
Don't even try to use the spell in someplace like forest without at least another +1 Size. Trees are 100 to 1,000 cubic paces each by rule (+2 Size medium, +3 Size large). So enough for 10~100 trees with the default +3 Size. How many trees do you walk past on a seven mile hike? And we are not even counting underbrush.
The "bare trunks" are cosmetic, in that Perdo can disintegrate or just kill things. It is the same as a spell that kills a person and leaves their body.
You can also rationalize legacy spells as being the result of the experimentation rules. Side effects and special or story effects do occur, from time to time, bending the rules.
This is one of those spells invented quite clearly player of an early game designer, (or perhaps an early writer of Ars themselves) and enjoys special protection. Don't overthink it. Sometimes a player wants a cinematic effect rather than immediate effect.
Honestly I don't feel that Treading the Ashen Path is that bad as an example spell to take for precedent.
The thing that it does is uses the Group target nearly as if it were a duration. Much as this sounds like madness, this sort of creativity is explicitly encouraged by the book when you create formulaic spells. You should not be able to reproduce the effect using these parameters spontaneously, because it does not closely follow the rules, but the guidelines for making formulaic spells explicitly permit bending the range, duration, and target rules at the cost of a magnitude or two (which it does pay for with the +1 fancy effect).
From the DE, p.306:
Each category of Range, Duration, and Target is described below. The categories described here were built into the structure of Hermetic magic by Bonisagus. All Spontaneous spells must conform to these requirements (the magus is making the spell up on the fly- he cannot also push the limits of magic theory). Formulaic or Ritual spells, on the other hand, can be invented with Ranges, Durations or Targets that are not li sted here. T his is usually slightly more d ifficult than if the closest category were used, but is largely left to troupe interpretation.
It doesn't use the Group target like a Duration. It affects the Group that you're Touching (with your feet, presumably) throughout its Momentary +1 fancy Duration -- which is effectively the While duration from HoH: MC before that book was written. (It even ends up at the same level you'd get if someone with the correct Mystery invented it with the While Duration.)
While you are walking it destroys the Group of plants that your feet are touching.
This spell was originally invented by a magus of House Flambeau, and he was awarded a prize for it by his primus.
If this were just a normal use of guidelines and R/D/T, it wouldn't be good enough to qualify for archmagus, let alone a prize. This should probably be read is it was some sort of result of experimentation.
You are misunderstanding what I mean. In a conventional sense, the "duration" of the spell is determined by how many plants will be destroyed (averaged into a result of "after 7 miles" to makes it easier for SGs), and how many plants will be destroyed is determined by the Target being Group and having Size magnitudes added.
The Duration, however, is simply Momentary, as the spell's effect happens in a moment, causing you to have an aura that continues until the size magnitudes "run out."
It is true that this is a nonstandard way of applying the guidelines, and this is my point, that such nonstandard ways of applying the guidelines are explicitly permitted.
I would personally simply say that the RDT parameters are underspecified if you had wanted to use them generally or spontaneously, but leaving them underspecified when working with a formulaic spell is fine, as long as your troupe agrees that the final level is fine.
If a treatment were to be made to make the RDT parameters more general, such that new spells could be designed with them, I might write them up like so:
Exhaust Targets (Duration): The spell affects multiple targets, and the effect lasts until the fixed number of targets it may affect has been exhausted. As a default, up to 10 base individuals can be affected, subject to increasing or decreasing number of larger or smaller size, as Group, and this can be increased with size magnitudes. This Duration is only useful with dynamic container targets, as otherwise the spell cannot begin to affect a new target after it is cast. This category is the same level as Concentration, and the duration of the effect on each target must be paid for as a second Duration, e.g. one additional magnitude is required for a Diameter duration effect.
Aura (Target): The spell affects valid targets within 10 paces of the caster, as a dynamic container. This category is the same level as Group.
This Duration and Target could have been specified when the spell was created and noted as Special, but because of the flexibility of RDT parameters in formulaic spells, I don't think there's much point to specifically doing this unless the player wishes to integrate them with a Breakthrough.
Moreover, I don't think that While nor Group are appropriate to Treading the Ashen Path if you do try to stat it that way, as Group requires that the targeted Group be "separated from any other things of the same type", which would not work if you wish to affect only the grass at your feet, as it is not separated from the grass on the rest of the field. Moreover, you need a Dynamic Container to begin to affect things only after the spell is begun to be cast, and Group is not such a Target. Add atop this that While (walking) would not so limit the path of destruction to 7 miles of walking, meanwhile subject to a little wiggle room, the size magnitudes about line up with the amount of extra grass to be affected.
What I mean to get at with this is that regardless of which particular tack you take when trying to stat out Treading the Ashen Path, you need to flex the RDT a little, and this is explicitly allowed by the rules, which means, I think, that not only is the specific effect of Treading the Ashen Path one which should be taken as precedent in what sorts of effects can be created, it should also be taken as a guide for how flexibly to interpret the RDT guidelines when inventing new Formulaic spells.
When working on DE I identified this and The Trackless Step as problems when people extend them. The Trackless Step received an erratum:
This spell draws on pre-Hermetic traditions, and does not perfectly fit the categories of H ermetic magic.
I suspect the reason Treading the Ashen Path did not is because this statement about the prize does imply an experimental result since nothing else about it would warrant a prize.
Another way to look at it: "If you're not arguing about your new Formulaic spell with your troupe for at least 10 minutes, you're doing it wrong." - Tarquelne, Follower of Tytalus
Checking the records, I see Treading the Ashen Path received the "Made the Primus Laugh," prize, and an Honorable Mention for the coveted "Aggravating the Fey" award. (Recently recast as "The Silvan Diplomacy Scholarship," after criticism from House G. The winner is given a pawn of vis and allowed to hide, I mean study, at Castra Solis.)
Don't overthink it. Sometimes a player wants a cinematic effect rather than immediate effect.