D&D 5E Using 3d6 for skill checks

[davep123]

Like many DMs, I use a lot of house rules in my games. However, recently I was a player in a game that used the RAW for everything. Most of my house rules I was happy to live without, but the one house rule of mine that I constantly yearned for in the new game was using 3d6 for skills checks.

3d6 gives the same average (10.5), but the results are clustered much more heavily in the middle range. This means that characters will more reliably succeed on the things they’re good at and fail at the things they’re not. It also means that even small differences in scores are significant. Using 1d20 for skill checks, especially at low levels, often leads to frail wizards successfully out-muscling fighters and dim-witted barbarians out-Arcana-ing wizards. With 3d6, those things can still happen, but they’re much less likely.

When I was playing the RAW game, I found myself choosing not to attempt things my character wasn’t good at, e.g. kicking down a door with 8 Strength, even though my character had a reasonable chance of success and the fighter had tanked a few rolls, because I didn’t want to steal his spotlight by encroaching on his schtick. If we’d used 3d6, my character would have been almost guaranteed to fail and the fighter more likely to succeed, which is how I think it should be.

Have any other folk tried 3d6 for skill checks or heard of anyone else who has? We’ve only played in the low-level zone, so I’d be interested to hear if anyone has tried it at higher levels and had any success or discovered any issues.

 

[Ancalagon]

Interesting. I've heard of people using 2d10 to achieve a similar result. Unfortunately, I've never tried it myself.

 

[mellored]

I like it better, generally speaking. It puts more emphasis on being good or bad at something, reduces the luck, and enforces rolls more.

That said, i would only do it for big parties. If your running alone or with just 2 people, you want a chance to succed at rarer tasks.


2d10 is a middle ground.

4d4 is another option, but that might be too narrow a gap.

 

[Mercule]

I'm actually not a fan, at all, of 3d6 in D&D. It works in Hero because the math is already set up that way. The dials turn a bit slower, such that a +1 can be a big deal for an experienced character, but it's about the same cost to go from marginally trained (8 DC) to well trained (11 DC).

The D&D math is set up to work better with linear progression. It's not really that uncommon for, say, a Fighter to have a +3 strength bonus, a +3 proficiency bonus, and a +1 magic bonus. In the standard D&D math, that's a swing of 35% chance of success. If you happen to hit the "sweet spot" on the 3d6 bell curve -- which is reasonable in a balanced adventure -- that bonus nearly doubles (+66%, back of napkin). The net result of 3d6 in D&D isn't more realism, smoother progression, or anything like that. It's increased swingyness, which almost always works against the PCs.

So, I'm not opposed to 3d6 as a resolution mechanic -- I love Hero. I just don't think it fits well with D&D (or "d20") and would be extremely hesitant to play in a game that used it. If I did play, it'd almost certainly be expressly to watch the math.

I wonder, if each player were given the choice between using d20 and 3d6, how many would choose each? If given the choice for each roll, I wonder how it'd evolve.

 

[pdzoch]

The problem with using more dice is the chances to roll a number turns into a bell curve. The more dice, the more average the result. I suppose a crit on a 3d6 would be an 18, but there is no 19 or 20. There is a 5% to roll a crit on a d20, but only a .6% to roll a crit using 3d6. Since the game is about heroes, the chance to have critical success and critical failures is more important than being an average performer.

A 3d6 could indicate a task that a critical result would not indicate anything special (perhaps mundane tasks).

I do like the idea of letting the players decide. Those who live by the dice, die by the dice.

 

[Quartz]

4d4 is another option, but that might be too narrow a gap.

The original Traveller 2300 AD used 4d6-4

 

[jodyjohnson]

I'd be fine with 2d10 or 3d6.

My preference is go by the book which is - the DM decides, the dice decide, or a mix.

If rolling the dice will likely result in something nonsensical - don't roll the dice.

If the strong man can't move it - the Wizard doesn't get to roll. If it was pivotal for the task to succeed or trivial we don't roll.

 

[mellored]

Actually, i think it might make more sense if it varied by the task.

Some things require a flat skill level. You need to be trained or you'll never succeed. Having an 8 Str wizard lift more then a 20 Str fighter is an odd situation. So using 4d4 would make sense for strength checks.

Other things however, can be more variable. It makes more sense for an 8 Int barbarian to have heard of a piece of lore that the 20 Int wizard didn't. So using a 1d20 would make sense for knowledge checks.

Similarly, a trained fighter might roll 3d6 for his attacks, while a wild barbarian rolls 1d20.


Of course, that might get too complicated too keep track of all the situations.

 

[Mercule]

The problem with using more dice is the chances to roll a number turns into a bell curve. The more dice, the more average the result. I suppose a crit on a 3d6 would be an 18, but there is no 19 or 20. There is a 5% to roll a crit on a d20, but only a .6% to roll a crit using 2d6. Since the game is about heroes, the chance to have critical success and critical failures is more important than being an average performer.

To maintain the 5% crit rate, you'd want to have a crit happen on 16+ on 3d6.

 

[DEFCON 1]

I've done 3d6 for skill checks before and found it to be TOO average. If you look at the curve, it's very bulbous... meaning that the middle average results appear much more often than the ends, and that results in much less variance from the roll and much more impact from the modifier bonuses. Didn't end up working for me.

That being said... I *am* going to be using 2d10 for ability checks when I run Curse of Strahd, as the curve is much less steep. We're still going to see more rolls in the 10-12 range obviously... but we're also going to see 20% of all rolls still fall at either end (2-5 and 17-20). I'm very curious to see how it works out.

And in that regard, I also adjusted my DC chart to reflect the 2d20 roll scheme as well:

Trivial: DC 5
Easy: DC 8
Medium: DC 11
Difficult: DC 14
Hard: DC 17
Severe: DC 20