I want to make a ritual spell that creates a horse that has thicker than normal skin. Essentially combining wizards mount and doublet of impenetrable silk.
Since this is a CrAn ritual I see no need for any muto requisites. What would you add for the unnaturally thick skin? or is this still covered by the base create a mammal? I dont think it's such a major change to warrent base 50 magical animal.
Subsequent versions would make smarter/faster/more agile versions how would i base these?