Does the Penetration level of an effect that cannot affect a magus count towards whether an enchanted object can get through said magus's parma?
E.g., say a companion has a sword which can cast Demon's Eternal Oblivion on each successful strike, and the sword is enchanted with enough penetration that most demons have reason to be worried. If said companion takes a whack at a Renounced diabolist, would the sword's penetration count against the diabolist's parma, even though Demon's Eternal Oblivion doesn't work on magi?
The language on ArM pg. 85 seems to indicate that the penetration might count, but I'm not convinced.
That depends entirely on the sword and how the effect works.
If it is a strike that activates when the companion says 'activate', then the sword does not need to penetrate so long as it's inactive.
If it's a sword that activates upon touching (as in, the trigger is literally 'touch something'), then it has already gone through the parma upon the first touch, so it does not need to penetrate. What is resisted is the demon's eternal oblivion effect, though (or more accurately, it's ignored entirely since it only works on infernal might)
Now if it's a constant effect that is always on (or on for a certain amount of time, like diameter or sun), but is a touch range effect, then it needs to penetrate to do base damage against a parma magica, as the sword is actively magical at the time.
If the effect affects the weapon, then it will need to penetrate in order for the weapon to hit.
If the effect affects the person directly, then it will allways need to try to penetrate, even if it can't actually do anything to the target - this is because the targets sense of a magic attack is linked to its MR.
Note btw - that even a sword lodged inside you will need to penetrate MR for any magical effects.
How ironic would it be for a mundane to commission a verditius for a sword that kills instantly upon use, and yet the verditius makes it a sword that heals upon touch. The person, thinking he can get away without paying, tries using it!
Given that you cannot normally inbue a ritual into an item, it also makes for a perfect weapon of assassination. As long as you can secretly stab a person, and your healing spell is of Moon duration (or better yet, one of the conditional ones), you can be away and have them drop dead when most convenient.
Wind of Mundane Silence can knock down parma if cast at a high enough level of effect. But I think a targeted Parma buster spell would be a good way to get your magus in a lot of trouble really fast. Spells such as the Lancea Magica, which supposedly could penetrate Parma, were suppressed by the Order.
I let Lancea Magica loose in my saga. Basically, it is WoMS scaled down two magnitudes to affect only a single target, so it is not a breakthrough by any means. Any magus could invent it according to RAW, and then call it whatever they wanted.
Are there any spells that would also lower Magic Resistance?
Would it be original research to invent a Parma that could be used to lower another Magi's parma???
ex. Lower your own Magi's parma by X to lower another's parma, or Magic Resistance, by X
Using the Wind of Mundane Silence as a Guide I personally have a PC with the above named spell. It is designed to dispell Parma's.
By using the dispell a Specific Magic of level equal to spell level + 4 magnitues guideline he uses it as follows
Lvl (Spec)
Rg Voice
Dur Mom
Targ Ind
This spell will dispell any Parma Equal to or Less the 1/5 the spell level + 10.
Of course it must penetrate 1st. But not many young to mid aged magi have Parma's of 4 or above so for anyone with a reasonable Perdo Vim score, then getting prenetration from a level 10 spell is not too difficult
for example my PC
Perdo 14 Vim 6 stam 2 Talisman 4 Penetration 5 = 31 + Stress dice which gives an automatic penetration of 21+ stress dice. Assuming an average roll of 6 then you will usually pierce and drop a level 4 Parma of a Magi with up to 8 points of Vim.
Then there are arcane connections... but if you have those, then you have less of a need of hobbling Parma.
However the Quaesitors would look VERY dimly on this spell and more so on those Magi carrying it as is automatically a high crime waiting to happen as it can only ever be intended to be cast on another magi of the order!!!!
I agree it's surely something the Quaesitors would consider somewhat dubious. But it's not necessarially a high crime to cast it...indeed it would be something that the Quaesitors themselves would probably want to be able to cast.
It would be perfectly legal to cast this on someone who had been Marched, or to cast it on someone in a declared Wizard's War, or to cast it on someone who happens to have invaded your sanctum, or to cast it on a hedge wizard who has somehow stolen the secret of Parma Magica.
Lancea Magica?
Serf's Parma, but I believe it's in Houses of Hermes, True Lineages, Bonisagus Chapter. This is where the Parma Magica variants are also described, the Abalitive Parma etc. I've never used any of these, but they seem intersting. One must think very tactical to get the right one, though. Perhaps a cunning Hoplite should dabble in this.
Its on page 11 of True Lineages and tells how a 10th century Bonisagus invented a lethal direct attack spell that automatically bypassed Parma Magica. The Colentes Arcanorum had the research destroyed.