Twilight of Darkness

Maybe a silly question: do you need to earn faction approval? And if so, how? Just for fun, I gave 10 units to the mages, but they declared war on me... Is that the point?

Well, let's just say that if your reputation is high, opponents won't demand resources; instead, they'll help you with resources. If you reach 100%, the opponent will become an ally. If you reach -100%, they will declare war. There's also a chance that even with a good reputation, they might declare war on you. But in general, gaining reputation is not mandatory.