I've been thinking, from the Enchanted Items thread where it turned into ways people make money for their covenants, another way of doing it could be to create new animals or plants using the guidelines in the books.
But, I've been wondering about the Medieval mindsight and paradigm that Wizards in that time period would be operating under. Is it possible to say "I'd like to make a type of rabbit that has gorgeous, beautiful fur coats" and then CrAn ritual them into existence with the desired traits? I'm guessing the more exotic the specifications the more the higher the level of the spell due to "complexity".
My ultimate question is when does the limit of essential nature get invoked? Can a magus design an entirely new type of animal?
Ideas for making money could be:
-Making semi tropical and Mediterranean plants withstand the cold
-Making more docile versions of animals so they can be domesticated
-Bigger and better Horses
Other ideas could be:
-Creating wolves or lions to patrol an area around the covenant to keep mundanes away.
My first thought is that you could do so, but the "genetic engineering" would, as an unstoppable byproduct, turn the creatures into magical beasts, with magical might, which they would lose outside of magic realm/familiar, etc. reinforcement, returning to their "mundane" forms once the magic had "run out". So not a viable industry, but perhaps useful for custom creatures.....
I was under the impression that Creo Animal (and Corpus/Herbam) could only create things that were 'real', (possibly only things that the caster knew about well enough) so no creating winged horses (that could breed and live as a species - Creo (Muto) Animal with a duration are possible).
I also remember a discussion about Platonic Forms, which were the absolute limit on what could be creo'ed into existence, but that was probably part of an actual game rather than the rules as written.
Ah, but Muto effects can become permanent. Not deliberately, given the current state of the Art Magic Theory the Order uses, but it happens sometimes with botches. So it is possible, and might be a fruitful direction for Original Research.
You could use the Fertility Rituals in Ancient Magic(?) to do that - apply them to animals instead of human beings. Doing so doesn't get you magical creatures (per se), but it does get you a modified human/creature...
The Medieval paradigm does understand selective breeding. That's been going around for millenia. The different breed of dogs are a prime example: dogs for guarding sheep from wolves (sometimes of the two-legged kind), for herding sheep, for tracking prey, for running after prey, ratters, ... So there is at least some leeway as long as you are only doing what selective breeding could do. That does include the angora rabbit, bred for its long, soft wool. A 'glow in the dark' rabbit however crosses the line (it would take lifting some genes from a different organism), it probably would fall into the guidelines for creating a magic creature (complete with Ignem and Vis requisites). That, or some way to make Muto effectively permanent (that's actually not that difficult, Ring duration, magic items...) and breed true (that one is far more challenging).
One difficulty is that selective breeding is basically a trial and error process. You could simply create large number of rabbits (using non-ritual Creo), for instance, examine them to see which one is best for your purpose, then base your ritual Creo on that. That would fit the paradigm. Otherwise you'd be shooting in the dark with each ritual.
Other ideas of what you could do is use Intelligo magic to examine different breeds or varieties across Europe and determine where they would be the optimal variety given climatic conditions. Maybe use Creo magic to create more once you've determined the optimal one. Historically, huge productivity gains were made just be systematically testing all the different varieties that were around and keeping only the 'best' ones.
Semi tropical is probably outside the Medieval paradigm, since European people just didn't travel to the tropics. See the discussions of exotic Heartbeast in HoH:MC. Mediterranean plants, sure, during the Renaissance nobles spent huge amounts of money constructing building just to grow oranges and lemons. And grapes were cultivated far North of were they had any business growing naturally. But you'll still be limited in how much you can change the plants themselves. And the lack of sun will affect the taste of the fruits (or whichever part you eat).
Sure, that's exactly what selective breeding did historically.
That doesn't require anything new, but without some Rego magic thrown in it's a very dangerous thing to do. Even with Rego magic, that's not a very subtle way of doing things (stories about lions in Europe will bring in plenty of noblemen hunters eager to bag such a prestigious trophy).
Isn't animal genetic engineering what one of the projects in Hermetic Projects was all about? The project goes along the lines of creating manticores and the like IIRC, so mixing animals can be done with Hermetic magic
Now there's a hook to earn money! Make your Covenant into a big game Safari, getting money and influence from Nobles all over Europe. Heck, use the money to make more exotic animals, give the nobles a "real" challenge (While making sure to not actually kill a beloved son......).
Well, Frederick's court in Sicily has a colossal menagerie that includes Europe's first giraffe in this time period so you could easily get royal patronage.
I thought about having a covenant full of improved animals, but I thought rather than CrAn a single animal and hope it passed along its desirable traits, have a merinita with bloodline magic target the chief bull/ram/stallion of the herd/flock. Improving presence would make better looking animals with finer hides, improving stamina would mean they were less likely to suffer disease and give good quality milk & wool over time, improved strength bigger muscles and hence more meat.
It's all a good area to use the Major Magical Focus "domesticated animals" which I still haven't got round to using yet.