The great myth of Skulls versus Shields.

[Kroc]

I don't know how many times I have heard (and maybe even said myself) that offense has an advantage in this game because there are three skulls and only two shields. People usually says that this makes it easier to wound someone than defend against a wound. This is not true.

In order to successfully wound someone you have to roll MORE skulls than they roll shields.

To get down to some numbers, if offense had an advantage then the probability of a wound should be more than .5 when you roll an equal number of attack and defense dice. However if you roll one attack dice against one defense dice then the chance of wounding is
(probability of a skull)*(probability of no shield) =
1/2*2/3 =
1/3.

This means that 2/3 of the time there will be no wound, or the defender wins.

EDIT:

Originally Posted by Eclipse

What it actually has a greater affect on is the difference in greater offense vs greater defense.

Since this thread has been given the exalted "thread of the week" rating I just want to say that I now no longer agree with this post. Or I should say, I now understand what the myth is really based on, and its not a myth at all.

In his post (linke above) Eclipse got it in one, basically the marginal benefit of adding an attack die is higher than the marginal benefit of adding a defenese die. I checked this out using Sisyphus's tables and found that no matter how you slice it, in terms of expected number of wounds or a probability of a wound, adding an attack dice helped more than adding a defense die. On average with the probability of a wound adding an attack dice gave a 53% higher benefit, with the number of wounds it gave a 78% higher benefit.

So, the "myth" is true, but only if you understand its not talking about an ABSOLUTE advantage, rather a MARGINAL advantage. Gosh, the economist in me loves this.

Originally Posted by Kroc

(For those of you who forget your economics, the marginal benefit is how much the probability of a wound is increased by increasing the number of attack dice by one, or for defense the amount it is decreased.)