During the opening tutorial mission when you are in the darkened room and they flick on the lights, the Fallen there are crawling up walls and across beams being like stalking, menacing insects. Then for the rest of the game you [b]never[/b] see any fallen so much as climb over a small object let alone scale an entire wall. Such a let down. I thought I'd be blasting these guys off the walls and roofs as they scatter like bugs but nooooope.