I've always thought that the Fallen are, if not most difficult, the most [i]annoying[/i] ass enemies in the game. God help you if there is Arc burn [i]and[/i] lightswitch on a Fallen-filled Nightfall. Not too difficult, again, but JEBUS, getting one-hit melee'd in the back by a stupid dreg, or sniped across the WORLD for a one-shot makes me fill with pure rage.