My flambeau magus is about to begin inventing a spell to turn his body into flame. Why? Because it's cool. He's never done that kind of research before.... Just researching for the sake of the challenge itself, so I'm kind of excited by the prospect.
Anywhoo, it struck me today on my way to work that he wears a ring enchanted with a ward against flame. Will this interfere with the casting?
Also, am I right to assume that he'll still be able to walk around and do anything a normal "body" would do, except that as flame he wouldn't be able to hold onto anything, and his touch would be rather, well, hot?
I'm not even sure it requires any research. I'd probably suggest that such a guideline already exists, because the MuCo 30 guideline of changing a body into something insubstantial is really close to fire (it has little or no substance, but it does have heat) has an Auram requisite. I can envision an Ignem requisite being of equal level, or maybe a magnitude higher to account for the heat. I don't think the ring would be a problem, but it may require casting requisites if you want it transform along with him (Vim & Te). Anything that you can't transform with the casting requisites would either fall off of you or ignite, or both.
I believe that the description of ward against heat and flames does say that it keeps flames a fair distance away from the protected person. You could argue that this doesn't make any difference if the caster's body is flame or not it will just keep other flames away from it. I don't suspect that there is anything in the rules that will make the question not a matter of judgement by the storyguide.
Taking inference from cloak of mist (which is a questionable thing to do) and Conflagrative Servant (from MoH ) the answer appears to be yes. Taking guidance from the movement of fire elementals in RoP: Magic (also somewhat questionable) the answer appears to be no. Once again I think that its up to the storyguide, but if I were running the game I'd let the caster walk around. To do otherwise would be far less fun, I see it as frustrating the players desire s for no clear reason and no benefit. (YMMV).
Incidentally there is a spell to d this on page 4 of the Ranulf thread "Assumption of the Fiery Mantle" but it didn't garner much debate (largely because the other participants were busy with the matter of whether being significantly more flammable counted as a minor ability for muto corpus).
Erik, I just read your thread on Ranulf / "Assuming the Fiery Mantle" (nice name, that!). An added ability would be the ability to move through spaces that are too small for a human to fit through... I like the idea that water does him damage.
Would a [PeAu, T: Room] spell that destroys all the oxygen put him out? Thus kill him? Or would it just cause him to revert to regular ol' flesh?
(serf's parma) In order to also transform clothing and equipment, I understand that I'll need to use additional requisites. Do I need to add those requisites while inventing the spell? Or is that something the magus can add on the fly while casting, depending on what he's carrying?
I like the idea that he'd start to asphyxiate just like normal for both its mythic resonance and for its simplicity.
I said that they were casting requisites. I looked at the paragraph on page 115 of the core book about casting requisites to double check that answer. The rules more or less only tell us how to use casting requisites not when to use them so I'll stick with my answer.
Edit: The Muto Corpus guidelines on p 132 show clearly that these should be casting requisites rather than spell requisites.
You have to be careful with concepts like "destroy all the oxygen"- that's a very post-medieval concept. Obviously flames need fresh air, but I don't know the medieval concept of that. "Exhausting the soil" was a concept they understood; "Exhausting the air" might be a better way of phrasing it.
Peripherally, someone had to do an experiment to prove that the same thing sustained animals and flames. They put a mouse into a closed container where a candle had just burnt out and proved that the mouse couldn't breathe, if I recall.