Good afternoon Folks,
In last weeks game my GM tried out a new mechanic (on me) where the enemies took the Aim - Called Shot action to "bypass" my armor and effectively reduce my soak by two on those hits. At the time I was rather annoyed, since he managed to hit, but the more I think about it, the more I think the addition of two setback dice might have made the action worse for him rather than better (on average, obviously it worked out for him on that hit). I wanted to go over some of the math involved and I figured more eyeballs to check my math would be useful.
Before we get started, I wanted to set some ground rules. I'm not looking to have a discussion about whether this action should or shouldn't be allowed. I respect his GM'ing skills and my character is a Brawn based Brawler with a lot of soak. I respect the fact that he felt the need to ignore some of my soak to threaten me. What I would like to discuss is whether it was a smart move for him to do this from a mathematical point of view. Namely, if averaged out over a significant sample size, would he do more damage by not taking this action.
The first thing to do seems to be to set some parameters for our experiment. I suspect the results will vary significantly depending on the enemies dice pool and the targets defense so setting some baselines would be helpful. For starters, let's try to recreate the scenario I was in. I have a soak of 9 and def 1 the enemies were firing 10 dmg blaster rifles with a dice pool of YYGG vs Med range.
Test 1 - Regular Aim - YYGGB vs PPS (soak 9)
The Formula (Odds of Success * (# of Success + 10 (W. Dmg) - soak(9)))
Using that formula I got an average damage of 2.83
18.98% 1 0.37968
21.78% 2 0.65328
18.06% 3 0.72232
11.70% 4 0.58485
5.41% 5 0.32472
1.77% 6 0.12404
0.43% 7 0.03464
0.07% 8 0.00603
0.00% 9 0.0003
2.82986Test 2 - Called Shot Aim - YYGG vs PPSSS (soak 7)
For this test I got 3.06 damage
20.83% 1 0.83324
18.21% 2 0.91065
11.77% 3 0.70632
5.77% 4 0.40376
2.05% 5 0.16384
0.44% 6 0.03924
0.06% 7 0.0064
0.00% 8 0.00044
3.06389So in this particular circumstance, it looks like he was able to average about .25 more wounds by aiming his called shots. It's also worth that their odds of criting dropping by almost a third. All in all, it seems like a pretty even trade to me.
What do you guys think? Did you see any glaring math/logic errors?
I think it would be interesting to see if these results change for different range bands.
Edited by SladeWeston