For some reason, I always find myself with a vendetta against Epirus. Or more specifically, against Pyrrhus and his descendants, whom I like to hunt down and kill like the dogs they are. Really, once they are out of the way (which typically involves sacking Ambrakia and Epidamnos, and sometimes Thermon), then I leave them be.
Following that, I don't really have a specific preference - although the way my current Romani campaign is going each and every battle against the accursed Aedui is hard-fought and so victories are much the sweeter. The cost in Claudii and Fabii of my Gallic wars is pretty high - all the more expensive since I'm only trying to restore the power of the Arverni somewhat to provide some balance of power and maintain my overland supply routes to Hispania. It has nothing at all to do with expanding the benefits of Roman civiliation to those over-hairy northerners...
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