I was reading Cloak of Black Feathers when I thought it would be handy to have a spell to simply produce the cloak at will. When I got done designing the spell, I found it was pretty high level, but have decided to post it anyway because I have some gripes.
I used range personal because it produces an item meant to be carried or worn.
The Duration was Sun for +2 because I thought it inadvisable to have the cape disappear in the middle of using Cloak of Black Feathers.
When I look at the guidelines for Creo Animal, it is Base 5 to create an Individual and that is a single hair, hide, or tusk (as examples). There was nothing lower. It appears that a Base 5 Creo Animal Spell can create one feather. For Creo Corpus, Base 5 creates an entire human corpse. For Creo Herbam, Base 1 creates an entire plant. Creating a corpse of an animal is Base 10. Most other Creo guidelines can produce some of their subject material at a lower level than 5. Animals are supposed to be a "lower" order than people (Corpus), I thought. It just seems odd that it takes Base 5 to produce one hair, or twice as much Base level to create a corpse. Yes, that's complaining, as this spell level seems inordinately high for what it produces.
The Size was +3 because I thought 100 feathers were too few. Although I feel that 1000 feathers would be far more than enough, there wasn't a middle ground. I did think of using Group, but that is 10 individuals, so it would only get 10 feathers from a +2 magnitude shift, less than increasing the Size of Individual by +2 (which is 100 feathers).
The hierarchy of difficulty in Ars Magica seems to be, based on the guidelines:
Herbam, easiest
Corpus, middle
Animal, most difficult
Under this, it would thus seem that raising a human would be easier than raising an animal, but somehow at the same time, animals can be raised, but humans can't (I know, the "soul" thing).
Raven Cape 40
Creo Animal
R: Personal, D: Sun, T: Individual
This spell produces a cape of raven feathers that the caster may wear. It is helpful when a magus wishes to cast Cloak of Black Feathers, but does not have the requisite cape available.
(Base 5, +2 Duration, +3 Size, +2 Processed)
How is making the requisite item for a level 30 spell a level 40 spell?
I am almost willing to apply several negative magnitudes under the central rule, but that's terribly arbitrary, and I would have to toss on three of them to lower it's level below Cloak of Black Feathers.