Wednesday, April 20, 2011

Dice Probabilities in Savage Worlds

The odds in Savage Worlds are a little hard to decipher at first. This is mainly due to the fact that die rolls can "Ace". An Ace occurs when you roll the maximum number for that die type. When this happens you keep on rolling and total up the sums of all the rolls. For example, if you are roll a 6 on a d6, you get to roll again and total both rolls (if you happened to roll another 6, you can keep on rolling).

To make this even more complicated, Wild Cards (pc's and powerful npc's) get to roll a "Wild Die" along with their Trait die and pick the best roll. This is almost always a d6. Extra's (most npc's and monsters) do not get to roll a Wild Die.

This leads to some weird probabilities that you would not normally consider to be correct. Take a look at the tables below and you can see where the strange spots are. They usually occur where the maximum normal roll for a die type is. An example of this is that it is easier to hit a Target Number of 12 with a d10 (12%) than it is with a d12 (11%).

Wild Card's % Chance to Hit a Target Number by Die Type
  2 3 4 5 6 7 8 9 10 11 12
d4 96 83 63 50 32 27 19 16 12 8 4
d6 97 89 75 56 31 31 25 20 15 10 5
d8 98 92 81 67 48 38 25 22 18 14 10
d10 98 93 85 73 58 50 38 29 18 15 12
d12 99 94 88 78 65 58 50 41 31 21 11

Extra's % Chance to Hit a Target Number by Die Type
  2 3 4 5 6 7 8 9 10 11 12
d4 75 50 25 25 19 13 6 6 5 3 2
d6 83 67 50 33 17 17 14 11 8 6 3
d8 88 75 63 50 38 25 13 13 11 9 8
d10 90 80 70 60 50 40 30 20 10 10 9
d12 92 83 75 67 58 50 42 33 25 17 8