I've seen differing opinions. I'm of the opinion it can be anything from wolves and such to disturbing creatures that defy convention and description. We have daimons so there's no reason not to RP fighting some freaky creatures, though the specifics of the particular creatures you're fighting are yours to come up with. I do it based on the mood at the moment, really. I don't see why some wolves would be so damn powerful for larger monster groups so I usually RP some weird quasi-intelligent or mindless beastmen or horrors we must put down for the good of mankind.