Consider lycanthropy as well. Druids + Werestuff go well together, and you can feel free to ignore the usual "lycanthropes need to be omnivores or carnivores" line.
See, in this way, lycanthropy becomes an important plot point for infiltration. The animals don't trust 'nuthin' with thumbs, but once one of the PC's gains Weregoatism from some mad weregoat, they can infiltrate the organization and find out more about it. Indeed, an organization of lycanthropes (representing the "wild" animals opposed to the intelligent "domesticated" animals) could make for an interesting opponent group, hungrily stalking the intelligent animals, painting them as unnatural abberations who deserve nothing but wrath.
Maybe the druid is playing them off of each other, trying to marshall the animals into making weapons of industry and castles of wood, while milking the lycanthropes for all the rage they're worth. And maybe at the center of it all is a town with a slaughterhouse....(I'm thinking a lot of undead, too.

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Of course, seeing human evil in the dispassionate eyes of a beast is always interesting. Murder, necromancy, 'cannibalism' (which wouldn't really be cannibalism for these beasts, but meh), an inversion of the hunter-prey relationship (the barnyard animals don't have thumbs, so they need slaves to build their great works...slaves are humans).
This idea is so neat, I'm yoinking it for a large swath of Concordance (which loves that civilization vs. wilderness line of conflict!).....sweet.