Dice Talk: which one(s) & why

[fireinthedust]

So I've been thinking about the dice used in D&D, and other games, and wondering whether or not I could switch the various dice rather than use the d20. Or, if I don't do this, why d20 works.

I have yet to take a Stats course (in process), so I could use some advice:

If I used a d6 rather than d20, I'd obviously have lower numbers. Not only that, but I'd need different DCs to target (much lower), especially if the goal is to keep 50/50 as a hit-or-miss rule of thumb: is something a good challenge? Is the chance to hit it 50/50? Yes, good, that's great. If not, I have to adjust the modifiers or the numbers (with ranks in a skill, a magic item; or as DM just use lower DCs)

Also, the numbers are really close together. Most misses, with d6 DCs, are going to be relatively near by D&D standards: chances are I'll miss by 1 rather than more.

Also, if I use 1d6, as I get higer level, the modifiers become more random more quickly: if a low level challenge is getting a 6; and I have +5 to hit at higher levels, then that low-level challenge ceases to exist.

So the size of the dice determines:

1) The DCs I can set
2) The modifiers handed out
3) the speed by which different characters' different modifiers outdistance each other: so the fighter's BAB is so beyond the Mage's BAB there ceases to be a point to a mage challenging a fighter to a fist fight. By Epic Level in 3.5, they insituted automatic number incrase by 1, to thing like saves and attacks, and skills: epic thieves might be able to leap the crevasse, but epic wizards down on spells would never be able to get across.


Does this sound about right?

 

[Camelot]

Yeah, lowering the die size of the core mechanic die changes a lot of stuff that would require a huge overhaul of the system, and I have no idea how all the math would work out.

One interesting idea I had though was instead of d20, roll two dice, a d10 and any other die. The second die would determine if the d10 was positive or negative, and you'd add or subtract that to your modifier. The range is close enough that you could just shift down the DCs of things without changing anything else. This sets the average at a nice even 0 instead of an awkward 10.5. The only problem is that you can't actually roll a 0. I'm working on it though.

 

[fireinthedust]

Any experience with other systems, like 2d6 games?

I'm under the impression that rolling 2d10 would get a lot of average results. That means very few criticals, comparatively, for d20 games... and, now that I think about it, you wouldn't get natural 1 ever (unless it was 1 + 1, snake eyes... cool name for a bad roll...).

That in itself is a big deal, for d20 games. Could be alright, if everyone is min/max'd, like in 4e, to have high stats. However, fighting more powerful monsters, with higher defences, would be tougher because you'd maybe be less likely to get the higher die rolls needed.

Not a bad idea, really...