I've been thinking about the vermin created aplying Rego Animal 5 a matter. They are mondanes, so one Momentaneus effect can create, adding levels you could control it. I imagine, taht requisites you could get biggers (Muto) or that you can see whatever they could see (Intellego). But, my points are...
1)The variety of vermin depends upon where you live (so you can create typical vermin like one typical frog from France or one typical from one Island), with not need for more than one spell.
2)One mouse could generate from soil, right? Because teh Virtue verson comes from rock.
Interesting point. I'd not considered the matter, but I suppose it makes sense that a single spell could generate different types of vermin. I'd certainly allow it since it doesn't really introduce any extra flexibility since the determining factor isn't the caster's will, but rather the available substrate.
I believe so. According to A&A, mice are "...born of damp earth" so that seems a reasonable interpretation.
And lo PCs never needed to find food again, using rego animal to provide all of their food needs.
All the frogs' legs you can eat - mais oui! Seriously, my magus this way conjures up the occasional morsel for his familiar, so she does not go a-hunting in strange regios.