Baseline Values and an Aside on Probabilities
The base number of dice for a skilled entry-level professional is baselined at 5 dice. With 5d and a target number of 15, the chance of success is roughly 75% (in actuality it is a bit over, but close enough). As outlined in this previous blog post, this falls into the probability range that I find is most perfect, where a competent, trained, healthy individual beginning their professional career should succeed on almost-routine tasks (I say almost, as if it were perfectly routine there’d be no need to roll a test!) most times. And even in those instances where they fail their roll, rarely will it be too disastrous of a setback (especially if the player chooses to succeed at cost, which is further explained below).
By adjusting the dice pool up and down in increments of ½ dice (a d3) allows for roughly this progression of success chances:
3d | 10% |
3½d | 25% |
4d | 50% (actual is 45%) |
4½d | 66% |
5d | 75% |
5½d | 90% |
6d | 95% |
In graph form, it looks like this (courtesy of anydice.com):
In play, it is easy to remember that 3½d to 5d forms the middle ground of success probabilities. Anything less than 3½d is super unlikely to succeed, and anything over 5d is pretty much guaranteed to succeed.
Taken together, everything comes together nicely:
- A nice round target number that is easy to remember.
- An easily graspable number of dice that counts as “competent”.
- Enough dice to let beginning characters succeed despite modifiers while also tempting the players with extra actions.
- And an intuitively graspable notion of the chances of success.