2d10 vs 1d20

[Rageheart]

This may be an old topic, but I just read the article here
(http://www.frontiernet.net/~jamessta...NonLinear.html) about substututing 2d10 for all d20 rolls such as combat and skill rolls.

What is the concensus on this houserule? I am looking at possibly using it on my next campaign.

[Fax Celestis]

It's a solid rule, but you get far less miraculous sklls, checks, and hits, since you'l be rolling average more often.

See, I see a critical as a heroic (or antiheroic thing); as such, I force most of my NPCs (those without class levels, anyway) to roll 2d8 instead of 1d20. That makes it so that they can't critical, but have a marginally higher chance of success.

The main difference between 2d10 and 1d20 is the bell curve. I won't do the math, but essentially you'll be seeing a lot of rolls in the 11 area. A d20, on the other hand, has a flat 5% to show any given face.

[Lord Iames Osari]

The link isn't working, but I think I've seen it before anyway.

I'm "meh". He makes good points - it is true that youare as likely to roll a 20 as any other result. However, the odds are 19 to 20 that you won't get a 20, and 18 to 20 that you'll roll neither a 1 nor a 20.

[Rageheart]

It's a solid rule, but you get far less miraculous sklls, checks, and hits, since you'l be rolling average more often.

See, I see a critical as a heroic (or antiheroic thing); as such, I force most of my NPCs (those without class levels, anyway) to roll 2d8 instead of 1d20. That makes it so that they can't critical, but have a marginally higher chance of success.

The main difference between 2d10 and 1d20 is the bell curve. I won't do the math, but essentially you'll be seeing a lot of rolls in the 11 area. A d20, on the other hand, has a flat 5% to show any given face.

I plan to use the Action Points mechanic from Ebberon as well ... to make it more Heroic. but this would eliminate the Dumb Luck factor

[Zophiel]

The link also didn't work for me, but as mentioned above, the frequency of rolls is skewed heavily toward the middle with the 2d10 mechanic. This makes criticals less frequent, so certain feats and weapon properties are likely to diminish in significance without making alterations to the way critical hits operate as written. Also, it's impossible to roll a 1 with this mechanic, although you could substitute a result of 2 as a critical fumble. Out of every 100 rolls, the number of times you will roll a given result for the 2d10 and 1d20 mechanics will look like this:

{table]
[tr][td]Result[/td][td]2d10[/td][td]1d20[/td][/tr]
[tr][td]1[/td][td]0[/td][td]5[/td][/tr]
[tr][td]2[/td][td]1[/td][td]5[/td][/tr]
[tr][td]3[/td][td]2[/td][td]5[/td][/tr]
[tr][td]4[/td][td]3[/td][td]5[/td][/tr]
[tr][td]5[/td][td]4[/td][td]5[/td][/tr]
[tr][td]6[/td][td]5[/td][td]5[/td][/tr]
[tr][td]7[/td][td]6[/td][td]5[/td][/tr]
[tr][td]8[/td][td]7[/td][td]5[/td][/tr]
[tr][td]9[/td][td]8[/td][td]5[/td][/tr]
[tr][td]10[/td][td]9[/td][td]5[/td][/tr]
[tr][td]11[/td][td]10[/td][td]5[/td][/tr]
[tr][td]12[/td][td]9[/td][td]5[/td][/tr]
[tr][td]13[/td][td]8[/td][td]5[/td][/tr]
[tr][td]14[/td][td]7[/td][td]5[/td][/tr]
[tr][td]15[/td][td]6[/td][td]5[/td][/tr]
[tr][td]16[/td][td]5[/td][td]5[/td][/tr]
[tr][td]17[/td][td]4[/td][td]5[/td][/tr]
[tr][td]18[/td][td]3[/td][td]5[/td][/tr]
[tr][td]19[/td][td]2[/td][td]5[/td][/tr]
[tr][td]20[/td][td]1[/td][td]5[/td][/tr]
[/table]

[Rageheart]

Well, the article does suggest that for Criticals you should ensure that at least one D10 is a natural 10. thus:

an Axe would crit 1% of the time, instead of 5%
a Longsword would crit 3% of the time, instead of 10%
a Scimitar would crit 5% of the time, instead of 15%
a Keen Longsword would crit 7% of the time, instead of 20%
and a Keen Scimitar would crit 11% of the time instead of 30%

Less good hits, but less Crit fumbles too.

And yes feats or enchantments relying on a critical to function would suffer for the change. :-/

[Zophiel]

Yes, that's a very significant drop in critical hit rate. Note that this also makes properties like Fortification for armor, and critical hit immunity of monsters less significant. The monster crit immunity does also indicate immunity to other things, like sneak attacks, so this does not completely weaken the monster, but these are things to be aware of.

You might want to increase the threat range slightly for weapon crits, especially if requiring one of the d10 rolls to be a natural 10. The exact change will depend on the flavor of game you're shooting for, of course, but it could be something to play with. Alternatively, or perhaps in addition to minor crit range increases, consider slightly increasing the multiplier for critical hits. This will help offset the reduced frequency. Yet another possibility might be to remove the confirmation roll and simply say that a crit is a crit. I believe this might impact some class or prestige class feature, or weapon enchantments, but something is going to be impacted somehow no matter what.

As for the critical failure chance, I suppose you could say that a natural 1 on one die and a result from 1-5 on the other die results in a critical failure. This should occur roughly 5% of the time, but I've been at tables with some gamers where this would create a rather unamusing rendition of "Who's on first" as the player tries to figure out what's going on with his die roll. And for that matter, if you start picking the die rolls apart that much it may be time to just consider converting from d20 to percentile dice.

Then again, if your players really trust you to be fair and aren't overly mechanics-driven, you could use something like this to keep them guessing. For any result in which neither a 1 nor a 10 was rolled, simply add the dice together. When a 1 gets rolled, check to see if the other die result is odd or even (or between 1-5 and 6-0, whichever way you want to split it), and just tell the player that they either fumbled or didn't. You will have decided secretly what the criteria for determining the fumble would be, based on the second die result; as long as you're consistent from session to session, or fight to fight, or use a 'batting order' of criteria or whatever, it will still be an unbiased decision. Come to think of it, you could do the same with critical hits, although that would get more complicated, since the critical threat range is not fixed. And of course, if you're using the action dice option from Eberron, you will also need to decide what to do with the action die roll in the case of fumbles and crits. In any event, it's your game, so make it as complex or simple as you'd like. :)

[Rageheart]

Personally I like the idea of a critical fumble on a pair of snake-eyes.... then make the fumble more serious then a "oops, you drop your weapon"

"You accidentally nick your self with your dagger... what? ...poison huh? roll your Fort save."

[Lord_Arkaine]

If you prefer averaging out numbers, a more popular tool is 3d6. 18 is a crit, 2 is a failure.

Makes it more averaged out.

[NEO|Phyte]

"You accidentally nick your self with your dagger... what? ...poison huh? roll your Fort save."

Poisoned weapons already do that on a nat1, although you get a reflex save (iirc) to avoid getting yourself with your own poison.

[martyboy74]

If you prefer averaging out numbers, a more popular tool is 3d6. 18 is a crit, 2 is a failure.

Makes it more averaged out.

How do you roll a 2 on 3d6?

[LordOfNarf]

How do you roll a 2 on 3d6?

I think he meant 3, and there is a huge section in unearthed arcana about 3d6, I did a chart of it, I'll post it later if i have time.

[Peregrine]

UA's 3d6 rules are also up at d20srd.org.

[NullAshton]

Yeah. Critical hits are adjusted to approximately the equivalent scale on 3-18.

And critical fumbles is, again, a stupid idea. On a 1d20, there's a 1 in 20 chance of you doing so. In the 2d10 system, there's still a one in a hundred chance of doing that. Unless you're swinging something like a madman hoping you'll hit something, you're not going to cut yourself with a sword or anything like that.

[Mike_G]

I disagree.

I've seen people do it.

Not often, nut seen it.

In combat, a poor attack can rebound off armor and hit you, or (given the abstarct nature of HP) you could just pull a msucle making the attack.

Hell, using a two balded sword and not cutting yourself would be impressive.

I'm a paramedic. Half my job is people who managed to use a tool wrong. And generally, the board wasn't swinging back or dodging.

[Lord_Arkaine]

Considering each person in D&D is at least a professional in their chosen job, I'd hope they wouldn't be making such wildly inaccurate swings and jabs. Precision is preferred over random chaos. A person may get luck now and again, such as with 18, but keeping the rolls averaging out around 10 helps keep the idea that in swordplay, the better swordsman wins. It doesn't come down to who rolled better.

[Arakune]

you can also swith to 4d6 to a realy heroic game too.

[Lord_Arkaine]

That kind of exceeds the boundaries of the game being measured. The idea behind 3d6 is that the range is 3 to 18 with the average STILL being 10 or 11. On top of this, you lose 2 points from the top but gain 2 points on the bottom.

Having 4d6 rolls would ensure the minimum you can roll is a 4 and would actually offer a maximum that exceeds 20, something not really intended, as well as having a higher average.