One of my players has just noticed the "total change" guideline for MuVi on page 159 of the main rules. This has raised some questions.
If you use MuVi to change the TeFo of a spell while it is being cast, does that mean the caster has to recalculate their Casting Total with the new TeFo?
I am assuming not, because your spell works on their spell external to them and so they are still pushing the original TeFo in but just getting something else actually happening.
If you invent one of these spells as a Formulaic, how restricted are you at cast time with how much you can vary the target spell and/or the resulting spell?
Presumably to follow the normal hobbling of MuVi there has to be at least one version for each Form. But would that be the original Form or the new Form or do we need 90 different ones because Ignem->Auram is different to Ignem->Terram and even Auram->Ignem?
Or do we need to be as specific as "converts any Auram spell to an effect with the same R/D/T and general effect as Pilum of Fire, varying the damage to make it the same level as the original spell"?
Or "converts Pilum of Fire to any Auram effect of the same level"?
By RAW "Note that a spell invented according to one of the guidelines below will change another spell in a specific way". Nor would I require recalculating the total. Finally, it would require a different spell to transform each form. Finally targets are not changed.
I think the most confusing bit is "the same effect every time you cast it on a specific spell". You can make a spell that extends the duration, or boosts the power all using one guideline. So one Muto Vim spell might allow for turning Vim spells into light, and another fire. They would have all the same guidelines, durations ranges, and such, but they would have different uses of the guideline. Look at mirror of opposition for an example of how its used.
I would say no. Look at mirror of opposition.
I would also say no. You don't need to be that specific with the Auram spell.
Are you saying you can't change Target (or even R/D/T) when you are changing Tech and Form?
Where is that quote from? I haven't seen that bit.
Yes, I understand that.
Those are fairly limited subdivisions of Vim->Ignem.
Yes, I understand that.
I'm sorry, I don't find Mirror of Opposition a very useful example. It doesn't change the Form and often won't change the Technique either (I would have thought the opposite of most Muto effects was Muto and the same for Rego).
So can you give me some examples that aren't as specific please?
I would also say no. The original caster is, as you say, casting with the original TeFo.
I would say the second option. The effect of the spell should be about as flexible as that of any other formulaic spell, which means that it should produce one, specific, formulaic spell. If it is significantly more flexible than that, it allows you to spontaneously cast any TeFo combination as if spending Fatigue for a MuVi spont, without, in most cases, actually needing to spend Fatigue, and getting full Penetration. Since a magus with these spells is likely to be a MuVi specialist, that is really overpowered.
The multiple Forms are really a red herring, because these spells are most useful when cast on the magus's own spells. As a MuVi specialist, these should be MuVi, so "Transform Vim Spell to Pilum of Fire" is the only one you need.
Looked at like this, the guideline lets any MuVi specialist invent and cast any spell as a MuVi spell of twice the level. That's nice, but doesn't tread too much on the toes of specialists. It does mean that Mu 20 Vi 20 is equivalent to 10 in every Art, so a MuVi specialist is better than a generalist.
Bear in mind that "total transformation of spells" is part of MuVi; it is definitely a valid Major Magical Focus, and arguably should be a valid Minor Magical Focus. That makes Mu 20 Vi 20 equivalent to 15 in every Art. So, even with the requirement of one spell per spell, this is still arguably overpowered.
For this, you can add "flexibility" magnitudes as multiple canon spells do. Personally I'd go with +4 for a broad major focus (birds), +3 for little major focus like (birds living during day), +2 for minor focus like (birds of prey), +1 for a couple of possibilities (hmmingbird, ibis, eagle).
But, a true MuVi specialist would not have any MuVi formulaics because of that limitation of "flexilibity". He would have all his OTHER spells formulaics. Then use the MuVi spontaneous (with focus and all bonuses he can get) to do whatever he wants.
As for the total change with boost power, I have gone with /2 , -3 magnitude, and a Creo requisite. I gave it +2 magnitudes boost of power
So for example (from memories so I may do mistakes, not having books):
Mu(Cr)Vi 50
R: touch
Allow you to transform a spell up to level 15 (base 45-3 magnitude, /2) to any spell up to level 25. Penetration remains unchanged but you can reduce the target spell level, and the difference is added to initial penetration.
More requires ritual power (level 50 limit).
Once a MuVi specialist is able to spontaneously cast this, he can say "I'm a mutovim expert". Not before.
While it is true that most formulaics don't have choices when cast, it is certainly not universally true. For Instance Seven-League Stride (Main Rules page 135): "Transports you to any place within seven leagues either that you can see or that you have an Arcane Connection with." Which is a fair amount of choice. Or Phantasmal Animal (page 144) "Creates an image of any animal or beast up to the size of a pony". So a small number of related spells wouldn't be beyond the realm of pre-existing example spells.
I don't think you can argue a guideline is overpowered based on interaction with a Virtue specifically chosen to exploit it, surely that way lies madness .
FYI, we have ruled in our sagas that "magic" was a major focus (as was trees for herbam), and "transform, destroy, control, create, investigate magic" minor ones.
Magic in the sense of "spell with magical realm source", thus excluding items, faerie/infernal/divine powers.
Useful focus for your vim specialist if he wants to... but no more than the "necromancy" for your necromancer.
In a subsequent saga, we, helas, ruled that focuses were overpowered (characters with one and characters without were not equal in power or even fun in the eyes of the ASG...) and banned them, to my displeasure, but currently I play with it and "why not".
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