So I was running one of my players through a fight just to give the system a shake down and we hit a small snag: what happens when a character is surprised?
I seemed to remember reading somewhere that their AV drops to 0, and rereading the dodge section that seems to make sense.
However, this brings up the next question: Doesn't that make intrusion /heinous/? I had a group of mooks and a named NPC attack him. His Perception was avg (5) and they only had a meager intrusion, but since he screwed his roll (final value 2) they would have easily trounced him (it seems).
So, do mooks get this advantage? Do PCs die from assassins in the dark? Did I run it correctly?
It has been forever since I've run a regular Feng Shui game, so I don't remember how I handled those things when they came up. However two possibilities occur to me off the top of my head.
The first is to reduce the Dodge AVs of all surprised characters by 5. Mooks would fall very easily (a Killer vs. AV 7 mooks could drop 8 on a break-even roll), but named characters, though other named characters would have a good chance of nailing them, would still be hard for mooks to hit (that same Killer gets jumped by AV 7 mooks and they'd still need a +3 to do anything).
The second would be to use the Outcome of the Intrusion check that gives a character the drop as the number by which the Dodge AVs of surprised characters are reduced (a Thief gets the drop on a Killer, who has a perception of 7, with a break-even roll; the Killer's Dodge AV would be reduced to 6).
Both of these options give a pretty big advantage to those characters who can sneak around, especially the second, so I would suggest limiting to three the number of shots the ambushers can use before the fight begins in earnest. Of course if they wait a little bit before springing the ambush, they could reasonably claim a +3 aiming bonus if they go after only one target.
I generally play it so that if a character really and truly gets the drop on someone (requiring at least two intrusion rolls in combat) their target has defence 0 for one attack only. You can't pull the same trick twice in the same combat, either.
I did have to fudge a gradual increase when someone used ambush to launch a Flying Windmill Kick. They 79 points of damage, even so.