How does suffocation work with enchanted air and a magi's parma magica?

My players are, through inventive hypothetical spells, trying to understand the limits and nature of magic resistance.

Given ArM5's version of parma magica and an awareness of the pink dot loophole, how does magic air, suffocation, and the parma magica work?

For sake of argument, let us presume a stockade parma that cannot be lowered, and a sealed room that does not have access to refreshing breezes that is within an unfriendly Aegis otherwise inhibiting spellcasting.

Therefore, Without introducing house rules, what must be cast on the air in the room in order to suffocate a magi sealed in the room?

Note well that earlier editions of Ars Magica used a different (dispelling instead of repelling) version of the Parma Magica and I am not seeking those answers. Please cite your sources. Answers without citations will be downvoted.

Note also that this is not a Newtonian physics question. Sources describing the Aristotelian paradigm only, please.

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I don't know the full answer, but it has to be some sort of air-sculpting that gathers air that is away from the magus and pulls it even further away, creating greatly reduced pressure. This spell would also have to be incredibly strong since you'd need to remove about 2/3 of the air from the vicinity of the magus to knock them out (even then they could keep going for a while), and that would create pressure of ~700,000 kg per square meter. If you could really hold all that air back and physics worked normally, you might do better releasing it and letting the shockwave do the killing.... – Ichoran Oct 8 '12 at 19:04
I'm not sure the concept of pressure exists in the aristotelian paradigm. – Brian Ballsun-Stanton Oct 8 '12 at 21:27
If pressure doesn't exist, you can't suffocate them since the air within the range of Parma Magica won't leave. I'm not sure the concept of metabolism of oxygen exists in the Aristotelian paradigm either, so that layer of air may well be enough. – Ichoran Oct 8 '12 at 21:34
There is the idea of the exchange of air through the lungs, which the heart then uses for the creation of the vital faculty by combining the air with the natural faculty. – Brian Ballsun-Stanton Oct 8 '12 at 22:09
I'm still not sure what that means for the case where you have a thin layer of air around your body. Anyway, air sculpting. There are all sorts of indirect environmental effects you can use to bypass magic resistance (in many settings, not just Ars Magica). (By the way, I typoed. Only 70,000 kg/m^2.) – Ichoran Oct 8 '12 at 22:42

In the Parva Naturalia, from pages 286 onwards, Aristotle discusses the various theories of respiration.

His theory is that the lungs work to cool an organism and counteract the heat generated by the Fire/Soul that keeps a living creature moving. If you can't breathe, you heat up, until eventually you die.

So, to suffocate this poor mage, you need to increase the amount of Fire in the air. Transforming some or all of the air to fire ought to do it. He may be protected from the direct effects of the magic flame, but eventually his heart will overheat from the temperature.

As a side note, the concept of pressure is mentioned in this treatise. It's included in Democritus' theory that breathing helped equalise the pressure of the Soul particles inside the body and the Mind/Soul particles outside the body.

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+1 for citation given. Not an Ars Magica citation, but an excellent citation nonetheless. :) – lisardggY Oct 9 '12 at 5:35

The medieval setting certainly understood choking and drowning enough for the basics of this to fit within the setting. A ref to ArM core rules is not reasonably needed.

A side thought on this.

Given the scenario you describe (a magus in an air sealed room, where spell casting is greatly diminished) then you don't need to do anything to kill the magus. The lack of air in the sealed room will kill them; just be patient.

The enchanted air may or may not be repelled by the Magi's parma. This is because the Magi's parma will either protect them from the enchanted air, thereby they only have the volume of air left in the room so they die slowly; or they are affected by the tainted magical air which means they are dead very quickly.

However if you wish to kill the magus quickly, then consider removing the remaining air (Perdo Auram) with an effect on the air and Target: Room. The spell will work on the room, and it is irrelevant if the caster repels it or not.

If the air is stale, but being slowly refreshed (because the room is not truly air tight sealed) then the Magus can stay there without issue if their Parma Magica holds. Further it is a reasonably low level spell to create a small volume of air around yourself as a magus, so that you could survive for a while. It creates another ArM problem of surviving from magically obtained resources that do not provide sustenance, but perhaps leave that alone in this question.

I took issue with the pink-dot-silly-parma questions when they appeared year ago, especially when considering the small area of air around the caster. I just don't believe that parma was intended as the pink-dot version which is now popular in ArsMagica.

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Your belief is incorrect. A decade ago, when ArM5 was released and the Pink Dot Loophole "discovered", the game's designers acknowledged it on the ArM mailing list as the correct interpretation of the Magic Resistance rules, but believed it to be less-broken than any of the alternatives. – Dave Sherohman Feb 10 '14 at 11:44
The precepts in pink-dot have been around long before 5e, and my players had similar discussions around Parma back to 3e when we started. The official forums have stated that the pink-dot is their preferred and official stance, and also openly acknowledged that it is broken. Less-broken is not equal to "working properly" which is why each troupe needs to decide how they rule on these issues. – ironboundtome Feb 19 '14 at 7:11

Given the Pink Dot Loophole, there's no need to rely on Perdo Auram. A touch of Muto Auram, just enough to make the air "magical" for purposes of the PDL, is all it takes. The air will no longer be able to enter his Parma and the magus will suffocate, even as the grog standing beside him breathes freely.

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