fable 2's box art is just an update on the original fable box art -- same concept, which can be found used in many pieces of art where there's a good/evil contrast as a focus.
you're acting like these are super original ideas that these xbox covers invented. they are well proven concepts that these games happen to use. you could say they are both ripping off the original, but that's excessive -- the point is that it's silly and distinguished mentally-challenged to act like one of these games ripped off the other when neither are original concepts to begin with.
both fable and resistance 2 have good/evil concepts within the game -- it's not surprising they'd express that on the cover, and a mirror image is, like i said, a well established way to do this.