In the Covenants book it says that when using Magic (especially Rego) to produce crafted items you make a Finesse roll, the difficulty defaults at 3 higher than the difficulty for a mundane craftsman to make. I assume that would also apply for making an item out of nothing using Creo.
What if the wizard has the applicable Mundane skill at a decent level of mastery? Such as Craft: Weaponsmithing (Swords) and they wanted to either poof a sword out of the air, or make it from pieces of metal? Would they roll their Craft skill instead, or would their Finesse roll have the lower Mundane difficulty?
I think craft skill or finesse is not relevant for Creo effects. Such spells create "perfect" specimens. The magnitude increases with the complexity of the created object, but whatever is created is created perfectly.
I would allow the use of a Craft skill instead of Finesse, and with the mundane (-3) ease factor to encourage magi to invest in mundane skills. I think it adds character to the, well, character.
I don't think that's supported by the rules, however. The rules as written seem to require Finesse, and Finesse alone.
Now this is just uncanny! I was reading the chapter in my chair and went to the computer to ask that exact same question - and lo! someone just had!
Did you mean to say without the -3 modifier? I think that makes sense. That would mean a craft score of +1 would be as good as a Finesse of +4, but a craft score of 0 wouldn't be as good as Finesse +3 (because of extra botch dice). And of course, the craft ability is not nearly as versatile as Finesse. A good trade-off, I think.
I was going to propose a house-rule allowing a bonus to the roll equal to the relevant mundane crafts skill (but no higher than Finesse) but I think I liked your suggestion better.
Being certain that you were incorrect regardingthis not being supported by the rules I quickly stomped off to grab my copy covenants and to my dissapointment I found that you are right. The Enchanted chef allowing the substitution of craft cook for finesse was the closest that I found.
In any case I've used this rule in play (albeit breifly) and I have not yet had any problems with it.
Actually in the ArM5 book pg 77 for the Creo entry it says an Int + Finesse roll is made to determine the quality of the item created.
I think though that I'll probably allow for those with the actual craft skill that would logically apply to roll that instead if they choose at the same difficulty a Mundane craftsman would have.
Now then, would a Finesse or a different skill apply for creating a living thing be used? For example could you use Animal Handling instead of Finesse to determine the quality of a created horse, or perhaps Medicine to create a human corpse?
I'd say no. "Natural things created by magic are always perfect examples of their kind", on the same page. Besides, that's stepping a bit too close to divine creation ex nihilo for my taste: only God crafts horses, magi just conjure them in the image He forms. I think that works better for ArM.
Thank you, thank you.
Now that I'm officially a Master, I can work my way into the Secret Masters of Ars Magica organization. I hear it's harder to get in, but they get a better health plan.
Of course, I'll understand if you can't talk about.