Combat Chance of Success Table
Defense
Score
Attack Score
5 6 7 8 9 10 11 12 13 14 15 16
5 4.50% 8.92% 15.54% 24.81% 35.85% 47.77% 59.69% 70.73% 80.00% 86.63% 91.17% 94.03%
6 4.37% 8.57% 14.87% 23.70% 34.20% 45.54% 56.88% 67.39% 76.21% 82.51% 86.97% 89.92%
7 4.18% 8.06% 13.88% 22.03% 31.72% 42.20% 52.67% 62.37% 70.52% 76.34% 80.67% 83.74%
8 3.91% 7.34% 12.48% 19.68% 28.26% 37.52% 46.78% 55.35% 62.55% 67.70% 71.84% 75.10%
9 3.59% 6.48% 10.82% 16.90% 24.13% 31.94% 39.76% 46.99% 53.07% 57.41% 61.34% 64.81%
10 3.24% 5.56% 9.03% 13.89% 19.68% 25.93% 32.18% 37.96% 42.82% 46.30% 50.00% 53.70%
11 2.89% 4.63% 7.23% 10.88% 15.22% 19.91% 24.59% 28.94% 32.58% 35.19% 38.66% 42.59%
12 2.57% 3.77% 5.57% 8.09% 11.09% 14.33% 17.58% 20.58% 23.10% 24.90% 28.16% 32.30%
13 2.30% 3.05% 4.18% 5.75% 7.63% 9.65% 11.68% 13.55% 15.13% 16.26% 19.33% 23.66%
14 2.11% 2.54% 3.18% 4.08% 5.15% 6.31% 7.47% 8.54% 9.44% 10.08% 13.03% 17.49%
15 1.98% 2.19% 2.52% 2.97% 3.50% 4.08% 4.66% 5.20% 5.65% 5.97% 8.83% 13.37%
16 1.90% 1.99% 2.12% 2.30% 2.51% 2.74% 2.97% 3.19% 3.37% 3.50% 6.31% 10.91%

1) This table shows a standard attack/defense chance of success. As an example of the math used to create this table:
If the attacker has a skill of 12 there is a 1.85% chance of him rolling a critical success (a roll of 3-4) and the opponent getting no defense roll.

There is a further 72.22% chance of the attacker  rolling a success (a roll of 5-12).

If the opponent has a defense roll of 9 he has a 37.5% chance of successfully defending, meaning that 62.5% of the time he will fail to defend. The final percentage chance of the attacker hitting his opponent is therefore:
1.85% + (72.22% x [1 - 37.5%])
1.85% + (72.22% x 62.5%)
1.85% +  45.14% = 46.99%

If you look up the Attack Score (12) across the top and follow that column down to the row for the Defense Score (9) you will find the chance of your success is 46.99% in the table.

 

Quick Contest

  A Wins B Wins Tie
+10 99.01% 0.45% 0.54%
+ 9 98.03% 0.99% 0.98%
+ 8 96.41% 1.97% 1.62%
+ 7 93.92% 3.59% 2.49%
+ 6 90.35% 6.08% 3.57%
+ 5 85.54% 9.65% 4.82%
+ 4 79.42% 14.46% 6.12%
+ 3 72.06% 20.58% 7.35%
+ 2 63.69% 27.94% 8.37%
+ 1 54.64% 36.31% 9.05%
+ 0 45.36% 45.36% 9.28%

In a standard Quick Contest roll neither party has an advantage, as both parties roll at the same time. Critical Success and Critical Failure have no effect, the only thing that matters is the margin of victory.

The first column shows A's margin of advantage over B; if A has a skill of 13 and B a skill of 10 then A's margin is +3, so he has a 72.06% chance of victory.

 


Resistance Roll Table
Defense
Score
Attack Score
5 6 7 8 9 10 11 12 13 14 15 16
5 4.50% 8.99% 15.75% 25.21% 36.52% 48.76% 61.03% 72.42% 82.01% 88.90% 93.56% 96.42%
6 4.37% 8.70% 15.29% 24.57% 35.71% 47.86% 60.10% 71.53% 81.24% 88.31% 93.15% 96.17%
7 4.18% 8.25% 14.52% 23.44% 34.27% 46.19% 58.34% 69.80% 79.68% 87.06% 92.24% 95.57%
8 3.91% 7.61% 13.40% 21.72% 32.02% 43.52% 55.45% 66.91% 77.00% 84.82% 90.54% 94.38%
9 3.59% 6.80% 11.95% 19.47% 28.96% 39.83% 51.34% 62.68% 72.99% 81.34% 87.77% 92.36%
10 3.24% 5.90% 10.28% 16.81% 25.26% 35.21% 46.08% 57.12% 67.54% 76.46% 83.71% 89.24%
11 2.89% 4.98% 8.51% 13.92% 21.15% 29.95% 39.89% 50.42% 60.77% 70.15% 78.25% 84.84%
12 2.57% 4.09% 6.78% 11.03% 16.92% 24.39% 33.19% 42.89% 52.94% 62.57% 71.40% 79.05%
13 2.30% 3.32% 5.22% 8.35% 12.90% 18.95% 26.42% 35.06% 44.47% 54.06% 63.37% 71.93%
14 2.11% 2.73% 3.97% 6.12% 9.42% 14.06% 20.10% 27.49% 35.96% 45.11% 54.54% 63.72%
15 1.98% 2.32% 3.05% 4.42% 6.66% 10.00% 14.64% 20.64% 27.94% 36.28% 45.46% 54.89%
16 1.90% 2.07% 2.45% 3.23% 4.63% 6.89% 10.23% 14.85% 20.82% 28.07% 36.63% 45.94%

This table shows the chance of succeeding in a Resisted Quick Contest. In a Resisted Contest one party is "attacking" the other, meaning he has to roll first, and only on a success does the "defender" have to make a resistance roll.

Some notes on the method used to compute these values:

1) In a Resisted Contest a Critical Success by the attacker means automatic victory; no resistance roll is possible.

2) If the attacker rolls a success the defender must make his roll by equal to or less than the attacker made his roll. This means all ties (which happen roughly 10% of the time) go to the defender.

The formulas used to compute the values on this table is similar to that used for the Combat Chance of Success Table (above), however due to the margin of victory being important the math is considerably more complicated. For instance, if the attacker has a skill of 12 and the defender has a skill of 9 you must figure the chance of the attacker rolling a 12 and the defender rolling a 9 or less, then the attacker rolling an 11 and the defender rolling an 8 or less, then the attacker rolling a 10 and the defender rolling a 7 or less, etc., etc., etc. Then you add together the chance of success from all of those rolls to figure the final chance of attaining a success on a given roll. For that reason I will not be providing an example for this table.

Copyright 2006 by Eric B. Smith
Back to Main Page