Game mechanic purupse of xd6 roles

[hcobb]

Originally Posted by Shostak

I recall having read that a feature of adding more dice is that the likelihood of rolling very close to the average expected value increases as the number of dice increases.

If I was doing an RPG I'd make the rolls on around 5 or 6 dice.
This way the players have a very good grip that they can set things up to almost always work and that once a play session outlier becomes the big deal of the session.

[TippetsTX]

Originally Posted by Shostak

I recall having read that a feature of adding more dice is that the likelihood of rolling very close to the average expected value increases as the number of dice increases.

No clue if that's true, but it certainly feels true. Sometimes that's just as good.

More dice means more variability in the numbers that can pop up in combination with each other even though, mathematically, the odds still adhere with a standard bell curve. And while it's true that you can, again mathematically, match those odds using incremental modifiers rather than adding or subtracting dice, I don't think the role of dice in RPGs can be defined simply by their mathematical effect on gameplay. I know that sounds odd, but to me at least, more dice just feels like a harder thing... just like rolling a 'nat 20' feels like a bigger deal than a 5% chance.

[Steve Plambeck]

Originally Posted by Shostak

I recall having read that a feature of adding more dice is that the likelihood of rolling very close to the average expected value increases as the number of dice increases.

Correct - as the sample size (in this case the number of dice) increases, the standard deviation (degree of variation from the mean) decreases. Roll a thousand dice and total them, and you'll find you're rarely very far from 3500 even though the range of possible results you might roll is indeed everything from 1000 to 6000. That's why rolling 5 of a kind is worth so many points in Yahtzee, or four of a kind beats most other hands in poker.

Originally Posted by TippetsTX

More dice means more variability in the numbers that can pop up in combination with each other even though, mathematically, the odds still adhere with a standard bell curve. And while it's true that you can, again mathematically, match those odds using incremental modifiers rather than adding or subtracting dice, I don't think the role of dice in RPGs can be defined simply by their mathematical effect on gameplay. I know that sounds odd, but to me at least, more dice just feels like a harder thing... just like rolling a 'nat 20' feels like a bigger deal than a 5% chance.

I agree -- tumbling a lot of dice is far more exciting! Even though you could adjust the odds if you wanted to make the results work out the same as only rolling 1 die. But what fun is that? :)

I used to have some fun using a pair of percentile dice for random encounter tables. They are very easy to draw up when you can just assign any percentage you want for the likelihood of a given event. But then you're only rolling 2 dice -- hardly exciting. Not that it needs to be when it's just the GM rolling.

I prefer not using both modifiers and dice number changes where possible, just because it's simple and clean. But realistically it's just not always possible, and sometimes you need both (at least by the RAW). For example, your target is defending so you have to roll 4d6 to hit, but you might still have a DX modifier, plus or minus, for any number of good reasons.

[sekalo]

When it comes to rolling multiple dice mechanics, it could be argued that West End Games (WEG) Star Wars d6 rules is the GREATEST!

The more dice you roll, has the high chance to have the total value around the average of all the dice. This is easy to dial in the target numbers and what is needed, since each dice is 3.5 average roll.

In my games I cap the number of dice rolled at 5, and if the skill has a higher level then 5, just take the average of the remaining values.