Here are some spells which demonstrate how to create animals in Ars Magica. The core rulebook spell The Wizards Mount (CrAn35) illustrates creating a horse, however it does not make clear the way the guidelines might be applied for smaller or larger creatures, or how to handle big groups of creatures. Here is some extrapolation.
The size calculations for how many of a particular size creature are interesting with the magical paradigm of Ars Magica. Individual creates one item, group creates ten times as many but also mentions that it creates ten times the standard mass of the standard amount, and that the base mass of the creature is a factor.
e.g. A base 15 spell creates one animal up to size +1, which can be extended by the Target: Group to up to an equivalent mass of 10x size +1 creatures.
This means that creating a swan is a level 15 base effect but creating a very large number of swans is very easy as they are so much smaller than a size +1 creature. As a swan is roughly equivalent to size -3 creature, a Target: Group version creates 200 swans (Houses of Hermes: Mystery Cults p.39 has a table of animal sizes).
The rough rule of thumb for creates sizes is a difference of +3 between two animals means a ten fold increase in mass, which is equivalent to a +1 magnitude in spell power required.
The mass of a standard animal using Target Group is:
- 1 animal of size +4
- 2 animals of size +3
- 4-5 animals of size +2
- 10 animals of size +1
- 20 animals of size 0
- 40-50 animals of size -1
- 100 animals of size -2
- 200 animals of size -3
- 400-500 animals of size -4
- and do on.
If for whatever reason the wizard might desire, a very large amount of animals could be created by adding additional magnitudes to the spell designs. Here are some worked examples:
Conjuring the Flock of Honking Swans
Creo Animal 30, R: Touch, D: Momentary, T: Group, Ritual
This spell permanently creates a very large flock of swans, up to 200 individual animals.
(Base 15, +1 Touch, +2 Group, Ritual)
You might think that swans was an odd choice, however swans illustrate the different size class calculation well and have some useful hermetic uses. Continue reading