Longsword vs. Scimitar.

The d20 is flat as hell. 2d10 provides a nice curve for character success.

d20 is so popular but at a cost of utility. 2d10 allows a level more roll-to-roll.

But, what are your experiences with d20 and 2d10? Is d20 really keepsake or no?

Your responses indicate a lot regarding how the D&D-related d20 has impact.

Thanks.

My experience is that 1d20 for attacks does actually create a bell curve because it generally requires multiple attacks to actually drop a foe. This means that while any given attack has a flat probability, in aggregate, combat is a bell curve.

Where the d20 needs assistance is instances where single rolls are used to determine the outcome.

Quote from: Chris24601;1087365My experience is that 1d20 for attacks does actually create a bell curve because it generally requires multiple attacks to actually drop a foe. This means that while any given attack has a flat probability, in aggregate, combat is a bell curve.

Where the d20 needs assistance is instances where single rolls are used to determine the outcome.

Are you taking modifiers into account? Sure, on a length, d20 can simulate a curve, but what impact do modifiers have?

I find the probability of rolling a 1 or 20 far greater w/ d20 than 2d10. Maybe my dice are emotional.

I'd need to see a diagram of d20 demonstrating a curve --- but I'm jaded. Show me good when I only see evil.

Not doubting any where as near as much just searching for PROOFS you say exist. Then I can be sated.

D20 = achieves 1-20 result without math = faster than 2D10

Oddly, I find the same people who can add 2D6 quickly get into trouble with 2D10. It's adding into the teens.

Quote from: Spinachcat;1087371D20 = achieves 1-20 result without math = faster than 2D10

Oddly, I find the same people who can add 2D6 quickly get into trouble with 2D10. It's adding into the teens.

Yes.

Is it adding, or the dice?

Quote from: Chris24601;1087365Where the d20 needs assistance is instances where single rolls are used to determine the outcome.

The d20 is good for combat, where the wild swings feel appropriate. And everyone loves rolling a natural 20.
But it's not so great for skill checks (where single rolls determine the outcome.)

I've never tried 2d10, but I have tried 3d20 take middle value. It worked, but some of the excitement in combat faded away.

20-sided dice are all about the 20-sided die. It's a fetish for most players at the table that know nothing about die mechanics.

Quote from: Shawn Driscoll;108737720-sided dice are all about the 20-sided die. It's a fetish for most players at the table that know nothing about die mechanics.

The depth of this comment is the beginning and end of everything I posted this thread about.

So --- yeah.

If you want to introduce a bell curve use 3d20 take middle.  It keeps the range of numbers the same.  In stressful situations such as combat revert to 1d20.

For D&D, the d20 makes a lot of sense.  You'd need to change more than the dice, to make 2d10 work well.  (It could work somewhat OK with a straight substitution, but there would be rough spots.)  

For another game (such as my never-finished homebrew), 2d10 makes more sense, because the game is built from the ground up to expect it.  Not least, the appropriate modifiers to rolls for d20 versus 2d10 are different.  They should be generally smaller and more rare for 2d10.  

I rather like 2d10 (or even 2d12) as a middle ground between d100 or d20 versus the GURPS/Hero 3d6.  The curve on 3d6 is a little steep and short for my tastes, when everything is a skill check.  The biggest drawback to 2d10 is that you are always rolling 2 dice instead of 1.  Strangely enough, the adding of the two dice isn't the problem for my groups.  The precise add against a target number only matters when it is close.  If you roll two low or two high numbers on the d10s, you probably know at a glance whether you made it or not.  No, the issue is that its twice as many opportunities for a die to go sliding out of control.  More, anything over one die makes it difficult to roll multiple checks at once.  I'm convinced that's why the d20 is so popular--handling time is inherently at an advantage with it, and that adds up rapidly.

Quote from: Theory of Games;1087372Yes.

Is it adding, or the dice?

Less combinations means that the combinations that there are can be chunked in long term memory more easily.

6 sided dice are also a lot more common generally - we're probably already familiar with them from board games (eg Monopoly), war games etc, so we already have those chunks.  We likely don't actually add 3 and 4 on two six sided dice.  We see the numbers (or pips) and recognise that they mean 7 without actually needing to do addition.*  (It's probably the smaller more common numbers too - but likely the context of the physical objects as well- context is very important to memory**.)

We're less familiar with d10s.  Likely we'd get there eventually if we played enough games with 2d10.

*This is similar to studies which have shown that chess grandmasters can remember the places of every single piece on a chessboard from a glance (as long as they're looking at an actual in progress game and not a random configuration of pieces.)

** If you have to study for an exam you should study in the same room as the exam if you can.  If you can't, you should make sure you study in different locations - because you need to make that knowledge independent of context.

Quote from: Theory of Games;1087366Are you taking modifiers into account? Sure, on a length, d20 can simulate a curve, but what impact do modifiers have?

Modifiers are irrelevant.

If you have to roll the d20 more than once to drop a foe, the overall results are going to start conforming to a bell curve on the second roll.

Let's say an ogre has about 18 hit points, you have two attacks per round, need a 11 or better to hit and your sword does 1d8+3 damage and a natural 20 does double damage.

You could, in theory, drop the ogre with one hit; a natural 20 and a damage roll of at least 6 on the die or better will drop it. But the odds of this are very very slim (far less than the 5% of simply rolling a natural 20).

But on average, its going to take you around three hits to drop the ogre. That means rolling to hit probably about six times, but if you roll well you might need only four, or poorly you might need eight or nine rolls.

If you repeated that battle twenty times, you'd see that the overall results of the battles (whether you win, how many turns it takes to win, how much damage you take in the course of winning) will fall into a bell curve distribution because each battle takes multiple rolls to resolve.

So many of these dice threads suggest somehow that a bell curve is somehow superior to a linear distribution. It doesn't model reality either way. They are simply rules about how to roll dice. Neither of these methods actually produce a more "realistic" or better game. One simply has an equal chance of generating any number in its set while the other is biased towards the middle. There is no magic, moral value, or advantage without context within a larger rule set.

I prefer linear distribution as it lets players more quickly determine their odds of success and allows them to accurately weigh risk and reward.

Hmm...

To a point.  The problem is what do you do with a 40% chance of failure at something your supposed to be competent at?  What can you do with that?  Does know your percentage chance of failure in advance make failure less frustrating?

In any case one doesn't usually calculate the exact odds.  And I know pretty well that if I need to roll a 15 on 3d6 then odds are it's not happening.  It''s enough to know the shape of the curve and have a sense of how steep it is.  It's only really opaque in something like the Old World of Darkness system when you have dice pool systems with variable target numbers.

No, I think the main disadvantage of bell curves (aside from potential handling time) is the same as their advantage, predictability. Linear dice tend to be dramatic when you want consistency and bell curves are consistent when you want drama.

Quote from: Chris24601;1087365My experience is that 1d20 for attacks does actually create a bell curve because it generally requires multiple attacks to actually drop a foe. This means that while any given attack has a flat probability, in aggregate, combat is a bell curve.

Where the d20 needs assistance is instances where single rolls are used to determine the outcome.

Yes basically this.

As soon as you create a subsystem that handles things with more than one roll the D20 is fine.  The big problem is flat one and done skill rolls.