Avenger Impressions

[nickf_mt]

probabilities

Here's the probabilities for rolling criticals with 2 d20 rolls:
20: .05 + .05 - (.05*.05 = .025) = .975 = 9.75%
19-20: .1 + .1 - (.1*.1 = .01) = .19 = 19%
18-20: .15 + .15 - (.15*.15 = .0225) = .2775 = 27.75%

Why are you calculating the chance of rolling *exactly one* critical though? From a gameplay perspective, it would seem more relevant to list the chance of rolling *at least* one crit between the two dice. (which of course, are simply 20:10%; 19-20:20%; 18-20:30%)

 

[Nikosandros]

Why are you calculating the chance of rolling *exactly one* critical though? From a gameplay perspective, it would seem more relevant to list the chance of rolling *at least* one crit between the two dice. (which of course, are simply 20:10%; 19-20:20%; 18-20:30%)

The other poster has the percentages right. You don't add the two percentages, otherwise the chance of rolling 11 or more on at least one die out of two would be 100%...

One easy way to calculate the proper percentage is to first calculate the odds of not rolling a single "20" and that's 19/20 squared (if you only roll a critical on a 20). You then subtract the result from 1 to get the chance of at least a 20.

 

[Kobold Avenger]

Why are you calculating the chance of rolling *exactly one* critical though? From a gameplay perspective, it would seem more relevant to list the chance of rolling *at least* one crit between the two dice. (which of course, are simply 20:10%; 19-20:20%; 18-20:30%)

Venn diagram - Wikipedia, the free encyclopedia

 

[nickf_mt]

Of course... obviously wasn't thinking it through earlier. Thanks for straightening me out!