Well, when i ran my games(i only played the ones set in amber rpg lately) i had to try setting up the enemies able to combat pcs who were rather more capable than them. I always left the element of chance in play, but actually i didnt do it completly narrativly like the game is supposed to be played. I did use dice, allowing for an element of chance to come into the conflict. The details werent that focused on but i did the blow by blow, i also tried to make the conflicts clear, of course holding some information back, which is necessary in amber imho. The enemies didnt shout tactics, depending on their goals they had a strategy and were quite determined to exectute it. Of course, that was for mooks, the villains had drama that made them chew the scenery. Anyway, i hope some of this helped:) Good gaming to you.