Hi everyone,
Where would such a change fit? 2x general+1? general+1 or half of general+1?
W
Serf's parma, I would think general +1. (middle guideline)
It makes no magnitude change to the spell: Sun = Circle, Individual = ring. (or whichever. With Circle/Ring, I can never remember which one is target, and which one is duration.)
This is the explicit definition of "easy" difficulty in MuV. The fact that it changes both Target and Duration at once is pushing it (you could add +1 to the difficulty if you cared), but we decided not to IMS. We call it "Transform the defending rampart", as it allows you to swap between circle and personal wards.
EDIT - My character blew an Insight to create his lvl 25 version of this spell that works both ways - ie, it can transform a personal ward into a ring ward, or a ring ward into a persona one. Otherwise, I'd rule that you would have to learn both versions separately.
It really isn't.
The explicit definition is "superficially change".
It is at best the implicit definition, as we learn from the next guideline that "A change in power of plus or minus one magnitudeis a significant change.
The "superficial change" guideline makes no reference to any game mechanics at all.
And to be honest, I'd argue that Ind vs. Circle is certainly a significant change.
And Sun vs. Ring probably is too,
Certainly obviates the need to trace out a ring in either case.
How?
It changes the parameters of your spell.
You'd specifically need to trace a circle for that (formely T: Individual) spell.
Or did you mean that you transformed it from Circle to Individual?
Sorry, I was going the other direction. 
Oh. then yes, absolutely.
Serf's parma - I was at work when I posted.
OK, so it's the implicit definition. At which point, I would argue that it's a superficial change due to the lack of change in magnitude - because if that doesn't count as a superficial change, there is very little that level of MuVi can actually do.
"change the sigil" seems to be the only thing I can think of (and in looking in the book...yep, that's the only example in there.) As such...I'd rather err on the side of "interesting stuff the description can do", rather than "lame concept that can only do one thing."
Tautologically, I define what follows the "Superficial" word as the definition of superficiality in this context. As such, here's how I read that text.
Easy -
may not change primary effect or power. (Effect: can't change which guideline you use. Power: can't add or subtract magnitudes)
However, that implies you CAN change the range/target/duration, as long as it doesn't affect power or guideline.
also implies you can change the specific implementation WITHIN a guideline (transform fish->dog, instead of fish->cat)
Medium -
can't change form/technique (implies you can change which guideline you use)
Can change the target (counts as a magnitude change: I read this as "change the specific thing being targeted a la Sorcerer's Fork", rather than "the circle/individual kind of target")
can add or remove +/- 1 magnitude in difference
Hard -
Change the Form/Technique
add/change 2 magnitudes
can't change target (although the medium version does.)
What can I say, I looked it up too, and that was a good thing, because I remembered the lowest definition as being "cosmetic" rather than superficial. 
Obviously I disagree on this. I can be persuaded, but changing parameters seems significant to me, even if I change them to within the same level.
You'll also notice that changing something to a lower guideline is also a significant change.
Absolutely! This is infact the primary use I see for this guideline, other than Shroud Magic.
In thinking about it a bit, I would imagine that most of these rulings are in there to prevent MuVi being used as an easy anti-magic.
"Oh, your perdo corpus spell is now perdo Animal! Shucky-darn, I'm not a rabbit. Doesn't affect me!"
or
"Oh, that Ball of Abbysal Flame is now only Range:Touch! - Ooh, it goes off at point-blank range." - Although there may be issues with "you can't change the target" with that one - so maybe the spell just fails, rather than going off in your hands.
Although now that I think about it:
"Wizard's Smug Defense" (muVi) - circular ward that reduces the range of any spell that crosses it by 1 magnitude. aka, "Intangible Tunnel? What intangible tunnel?"
Sure, use MuVi to change the spell so it doesn't affect you, it's fine... The devil is in the details. You have to fast cast the MuVi spell, and your penetration on the spell must beat the penetration on the opposing spell...
Like many things in this game, I was thinking in terms of pre-established wards.
Although that is another devil/details issue: what happens when an intangible tunnel (or that BoAF) hits the MuVi "reduce range by 1" ward? Does it go off at max voice range relative to the caster? Or does it go off at the edge of the ward? Or does it simply fail to go off? (I'm thinking "fail to go off", actually.)
EDIT - ah, it can't be used on non-Hermetic magic. So, no cheap anti-magic fields. And it can't be used on magic after it has been cast. So does that negate the whole MuVi ward effect? I'm honestly not sure of the practical mechanics of spell-casting. If the spell is in the air, speeding towards its target, is that part of the "casting"? As the travel time of a spell (once it has been cast) seems to be instantaneous, it seems to be something of a edge condition.
Oh, well, that's not possible with Muvi (changing pre-established wards).
You can't change a spell after it has been cast (set, if you prefer) with any of the Muvi guidelines (see the insert on the page).
Edit: Clarity to mention changing pre-established wards.
Hence the whole fast casting bit. You're timing the MuVi spell to the opponent's spell as he finishes casting it.
Hm. So, I guess MuVi works as an antimagic effect, in terms of efficacy, somewhere between the PeVi "affects everything at 1/2 value", and the "affects 1 thing at double value". It functionally can block MOST hermetic magic, in a counterspell effect, by reducing its range by 1. Although you'd have to have it at sight, so it'd be T:Ind, R:Sight, for a total of (Magnitude -2)
And you have the penetration issues, which technically, PeVi doesn't. It's a fair question to ask if a PeVi spell should have to similarly penetrate the penetration of an opposing spell. Given the limitations of Muto Vim as compared to Perdo Vim, though, since PeVi spells can be designed to take out non-Hermetic magic, I'm fine with PeVi having an edge in being used to counter spell.
Wouldn't work in my saga. Ward guidelines specify Ring/Circle as parameters, there are no personal wards (other than the ones actually covered by the guidelines).
Fair interpretation for wards...
I was probably fishing for trouble by going for two changes + wards mystery as my base case example.
What if, to simplify stuff, we would just took a Touch|Ring|Circle light spell and wanted to change it to a Touch|Sun|Circle light spell. Is this enough to bring it to General +1 or can this fit into the "superficially" bucket?
W
That one dies on being circle. No Creo spells bringing something into existance with T: Circle, not even light 
But no, it doesn't change my opinion.