Using d20 instead of 3d6 (DON'T KILL ME!)

[vivsavage]

I love the bell curve. Bell curves are great. But here's my problem -- modifiers aren't equal in a 3d6 system. For instance, when the GM assigns a penalty of -2, it means something entirely different to someone with a skill of 13 than it does to someone with a skill of 8. With d20, a -2 penalty is the same for anyone at any skill level (-10% on a 1d100 system). To roll an 8 or less with a 3d6 system gives you essentially a 25% chance to succeed, meaning that a penalty of -2 drops you to a 6 or less, or approximately a 9% chance...thus the -2 penalty drops you by 16% (or so). Now, if you've got a skill of 13 (approx. 84% chance of success) and you get a -2 penalty, that drops your chances to 11 (or 62%), meaning a drop of 22%. Maybe it's not a huge deal, but as a GM it makes me question my modifiers. Any thoughts? Would the Hero System work with d20?

[yamamura]

Re: Using d20 instead of 3d6 (DON'T KILL ME!)

 

I won't kill ya;) But of recent there has been a number of question wanting Hero to be more like GURPS (1 sec rounds) and now this (d20). Next thing they will want to do is get rid of way OCV and DCV is figured and then knock the number of stats down to 4 or 6. When will the madness end? I might be going off on a tangent here but I believe some people would be more happy with the other systems instread of trying to make Hero into them (not aimed at you Vivsavage, this is a tangent afterall). Or are they hoping for a hybrid system called GURPS Hero d20? Or is it the fact they have come off of playing another system and isn't all that familair with Hero's way of doing things? Well I am going do you all one better, I am going make BESM Hero;) It will have all simple to follow rules of BESM with all the complexity of Hero Bwah hahahahahaha!

 

G

G needs to go to bed............................

[KawangaKid]

Re: Using d20 instead of 3d6 (DON'T KILL ME!)

 

Isn't the point of the bell curve with the modifiers supposed to be like that? To reflect the heroic paradigm?

 

If two opponents with equal CVs square off, then it's more or less a 50/50 chance to hit with a slight edge for the attacker (Who dares wins!).

 

If there's a high CV vs. someone with a low CV, then chances are the person with the high CV will regularly trounce the low CV, with a very rare chance of the "lucky shot".

 

In the d20 version, you have always have a 5% chance of succeeding, true. But that also means that your experienced fighters will have a 5% chance of missing (through no fault of their own).

[Hyper-Man]

Re: Using d20 instead of 3d6 (DON'T KILL ME!)

 

while not all d20 is D&D I thought some might get a laught from THIS!

[Dust Raven]

Re: Using d20 instead of 3d6 (DON'T KILL ME!)

 

The differences between using a d20 and 3d6 for rolls are obvious. The significents of those differences aren't always so.

 

If there is a magic sword that helps the wielder wield it, who do you think is more likely to benifit from such a bonus? The expert soldier who's trained heavily with much more mundane weapons, or the wet behind the ears kid who's only recently learned how to use such a thing? Obviously it would be much more effecting in the hands of the vetran soldier, but will the advantage he gains really be equal to the advantage gain by the novice? A small bonus would be a lot to the novice, while it would take a much larger bonus to even make a difference to the vetran.

 

Same thing with equally skilled characters, but with different DEXs. The "edge" of gaining a +1 would logically mean more to the slower character than it would for the faster.

 

Penalties would work the exact same way. An expert would hardly balk at what would turn the novice into a disaster. The bell curve handles this perfectly, and in a way that a d20 can't even compare.

[philnicau]

Re: Using d20 instead of 3d6 (DON'T KILL ME!)

 

If it ain't broke why try to fix it??

[Snarf]

Re: Using d20 instead of 3d6 (DON'T KILL ME!)

 

I agree that the effect you've observed about modifiers was completely intentional. A difficult task is supposed to be meaningless to a master, difficult for the moderately skilled, and utterly disastrous for the novice.

 

But enough about that, as for how well it would actually work in practice, it seems possible to me. A roll of 10 is still the median, but there's no curve around it anymore. The range of the roll would expand some, now that you can roll 1,2,19, and 20. People would have to spend more points to make their skills really reliable, because of the greater range of the roll and lower predictability of having no curve, but that wouldn't break the system. If skills costs doubled with each level like GURPS, it would be a big difference, but skills have a flat cost in Hero, so it wouldn't matter that much.

[vivsavage]

Re: Using d20 instead of 3d6 (DON'T KILL ME!)

 

I didn't make my point well. I am NOT NOT NOT talking about making HERO into a D20/OGL system!!! All I'm saying is that using a twenty-sided die (instead of 3d6) to resolve test rolls would mean that any modifiers applied to the roll would be the same across the board, no matter what your skill level is. But with 3d6, a penalty is entirely different from a %age standpoint depending on your present skill level. Therefore a GM needs to take into account just what a -2 penalty (or whatever) is actually doing.

[tesuji]

Re: Using d20 instead of 3d6 (DON'T KILL ME!)

 

Obviously it would be much more effecting in the hands of the vetran soldier, but will the advantage he gains really be equal to the advantage gain by the novice? A small bonus would be a lot to the novice, while it would take a much larger bonus to even make a difference to the vetran.

 

You seem to be implying that the 3d6 makes this happen.

 

Novice OCV +4

Veteran OCV +8 (thru skill levels or whatever)

 

Both shoot at Novice (DCV 4) at range of 25m. (+4 DCV)

Both are handed +1 accuracy Bow.

 

Novice gains 9.7% (hitting on 21 more chances in 216)

Veteran gains 11.6% (hitting 25 more times in 216.)

 

It would seem that the bell curve here is making a small bonus more valuable to the expert and is doing exactly opposite of "A small bonus would be a lot to the novice, while it would take a much larger bonus to even make a difference to the vetran."

 

OF course if one closes the range to 5m, the differences are novice +11.6% and the expert +2.8% so there it does match up with your preference.

 

But at 15m, the novice gains 12.5% and the expert gains 6.9% so we again are flip flopped back.

 

It sounds good to claim the bell curve works its modifier mayhem in a pattern like "the novice gets more and the expert gets less" as that makes it seem logical if one buys that as reasonable and not that it is just more or less random.

 

What a bell curve does is say "the modifier means more to those at the top of the bell and less to those at the bottoms" and it doesn't care, bother with, or recognize how one gets to the top or bottom... high skill but difficult task, high skill but low attribute, low skill but favorable circumstances, etc etc etc its all the same. Who benefits the most from "a given modifier" like say "+2 for excellent tools" will vary between novice, professional and top man flipping back and forth between them from task to task and circumstance to circumstance.

 

With a d20, if you needs to roll, a +1 is the same for everybody.

 

Of course, that is "for better and for worse" so to speak.

 

Some will prefer the former, some the latter.

[TheEmerged]

Re: Using d20 instead of 3d6 (DON'T KILL ME!)

 

Having played a fair amount of d20, I can promise I won't kill you -- I can also say, with some authority, that I disagree with you very strongly. 2 of the 3 d20 campaigns I have personal or second-handed contact with have moved to using 2d10, and that's not by accident.

 

In theory, d20 sounds like a good, simple mechanic. In practice it leads to such wild chance probability, especially with skill scores, that your bonuses have to rank around +7 +10 before they begin to counteract raw random chance. This is part of the reason you'll hear the (in my experience-based opinion valid) argument that D&D based d20 is really only balanced & playable from levels 5 to about 13.

[Hugh Neilson]

Re: Using d20 instead of 3d6 (DON'T KILL ME!)

 

In theory' date=' d20 sounds like a good, simple mechanic. In practice it leads to such wild chance probability, especially with skill scores, that your bonuses have to rank around +7 +10 before they begin to counteract raw random chance.[/quote']

 

To me, this is the big difference. There are two components to success or failure in any given RPG task. The first is how skilled the character is. The second is the random chance of the die roll. The bell curve (3d6) makes the skill of the character more dtereminative of the outcome. The flat roll (d20) makes random chance a greater contributor to the outcome.

 

Neither is inherently superior. You're only able to choose based on personal taste. There would clearly be some differences in making such a change (eg. a 15- roll goes from virtual certainty of success to a 1 in 4 chance of failure), which means the change will have ripple effects. You would probably start to see players trying to buy higher skills, and higher CV's, to be more certain of success (or of not getting hit, for those characters relying on DCV rather than defenses - there's a reason d20 moves hit points up constantly), which would require some modifications to NPC's. How much extra GM work that means depends on how much you use published opposition, and to what extent you rewrite them already.

 

As I read your comments, you're only talking about task resolution, not (for example) changing activation and hunted rolls. That would have even more significance as you'd need to reconsider either the rolls or the point breaks, obviously.

 

OS: We don't kill people for these offenses. Excommunication is the prescribed penalty for blasphemy. [More seriously, you presented a change you are considering and the reasons behind it, and asked for input. The flamethrowers generally only come out for "This is the way it should be, and anyone playing differently should be flogged. Hero's failure to change the official rules makes them a dismal failure." threads.]

[Chiba Bob]

Re: Using d20 instead of 3d6 (DON'T KILL ME!)

 

Sorry ... take this Infidel!

 

 

.

[vivsavage]

Re: Using d20 instead of 3d6 (DON'T KILL ME!)

 

Having played a fair amount of d20, I can promise I won't kill you -- I can also say, with some authority, that I disagree with you very strongly. 2 of the 3 d20 campaigns I have personal or second-handed contact with have moved to using 2d10, and that's not by accident.

 

In theory, d20 sounds like a good, simple mechanic. In practice it leads to such wild chance probability, especially with skill scores, that your bonuses have to rank around +7 +10 before they begin to counteract raw random chance. This is part of the reason you'll hear the (in my experience-based opinion valid) argument that D&D based d20 is really only balanced & playable from levels 5 to about 13.

I actually agree with what you are saying. Some people on this thread seem to be under the impression that I am suggesting that a linear probability is preferable to a bell curve. This isn't the case at all. I love the results a bell curve gives, as it strongly favors skill over random chance. But, again, I am not talking about that aspect. I'm ONLY talking about the effect of applying modifiers. As a GM, I want to know precisely what effect modifiers have on a roll. With d20, d100, d10 (etc), the effect of applying a modifier is easy to ascertain. With a bell curve, they are not. That's all I'm saying. To reiterate: I love the bell curve. But the EFFECTS OF MODIFIERS on a bell curve have me questioning the mechanic.

[fredrik_nilsson]

Re: Using d20 instead of 3d6 (DON'T KILL ME!)

 

Any thoughts? Would the Hero System work with d20?

 

The group prior to the one I'm playing with now where more or less d20 fanatics, to the point that I even begun to make a sketched version of a d20 version of the HERO System.

 

I started a thread on the topic (Creating HERO d20), and to some degree the same question is discussed there.

 

Thanks to that one of the players in my new group is a hardcore GURPS fan the new group gave the HERO System a chance so I ended the project.

 

Anyway...

 

A few months ago I bought Urban Arcana from Wizards of the Coast. I think the book is actually quite good, and is talks about running the d20 system with 3d6. It should be to difficult to use the material in that book to run HERO with d20, since it's more or less "going the other direction".

[tesuji]

Re: Using d20 instead of 3d6 (DON'T KILL ME!)

 

In theory, d20 sounds like a good, simple mechanic. In practice it leads to such wild chance probability, especially with skill scores, that your bonuses have to rank around +7 +10 before they begin to counteract raw random chance. This is part of the reason you'll hear the (in my experience-based opinion valid) argument that D&D based d20 is really only balanced & playable from levels 5 to about 13.

 

BTW, i tend to agree that d20 works best in the ranges of 5-15 (i go a little firther than your 13). Fortunately, thats also the ranges i like to play.

 

i also agree with one of the reasons being that at those levels the "skill side" of the success fail is not dwarfed by (and does not dwarf) the die size side of the success/fail. This gets better, BTW in d20 systems where you get more skills or get feats/class items that allow you to exceed the level+3, such as in stargate which does both.

 

My general gut preference is for three elements: attribute, skill, and random to all be on the same scale (attribute bonuses 1-6, skills 0-6, roll a d6.)

 

What 3d6 does, or any dice pool does, is in practice give you similarities to a smaller die. 3d6, for instance is very much like a d10+5 in size (allowing for an open end on 1 or 10.) 80% of the results fall between 7-14 and bonuses for 3d6 fall somewhat grouped around the +10% for the d10+5 in that 80% range. In effect, you cut the die size by 50%. That means you get into "skill competes with dice" sooner but you also get into "skill overshadows dice" sooner too.

 

If i was going to replace 3d6 with a single die linear system here is what i would do.

 

Use d10+5 with open end for half a die

On a natural roll of 10, roll a d10 and add half it. So a roll of 10, 7 would be +19. A roll of 10, 4 would be +17.

On a natural roll of 1, roll a second d10, half it and subtract it. so a roll of 1, 5 would be +3. A roll of 1, 8 would be +2.

 

this gets 80% of your results in the 7-14 range, just like 3d6. Your "die size" wont change much.

this gets you ranges from 1-20 only needing to roll 2 dice on the natural 1 and 10.

this gets you linear modifiers. you always know what a +1 is doing, with the exception of the extremes of course.

 

its also pretty simple.

[BNakagawa]

Re: Using d20 instead of 3d6 (DON'T KILL ME!)

 

IMO, the bell curve exactly replicates my expectations when it comes to adding modifiers.

 

Consider: You have an average fighter and three possible opponents. One is far below average, one is average and one is far above average. (And by far, I'm talking at least 3 CV points difference)

 

Would it benefit your average fighter to have an advantage, say a +1 magic weapon in his fight against the chump? Not really, he doesn't need it. And the bell curve reflects this. He's already got a very good chance of hitting or blocking and the sword only bumps this chance by a little bit.

 

Would it benefit your average fighter to have the advanatage against an evenly matched opponent? Why, yes it would. Whaddaya know, the bell curve delivers with a large bump to hit, block percentage.

 

Would it benefit your average fighter against the stud? Well, not so much. And the bell curve comes through with a smaller bump.

 

Let's consider skills. You have an expert mechanic, a tinkerer and someone with no training at all. (15-, 11-, no roll, but the GM is being kind and giving him a 5-)

 

They need to perform some sort of repair and the GM rules that having the vehicle's owner's guide is worth a +1.

 

Does the expert really need it? No, a 16- is not that much better than a 15-.

Does the tinkerer need it? Well, more than the expert, as a 12- is quite a bit better than an 11-.

Will it help the guy with no skill at all? Not really, a 6- is not much more likely than a 5-.

 

All of this maps perfectly to my expectations of what a '+1' ought to be worth in different situations. It should have little to no effect in the extremes and quite a large effect in those iffy 50-50 cases.

 

I don't see a problem with the existing system.

 

$0.02

[tesuji]

Re: Using d20 instead of 3d6 (DON'T KILL ME!)

 

 

Let's consider skills. You have an expert mechanic, a tinkerer and someone with no training at all. (15-, 11-, no roll, but the GM is being kind and giving him a 5-)

 

They need to perform some sort of repair and the GM rules that having the vehicle's owner's guide is worth a +1.

 

Does the expert really need it? No, a 16- is not that much better than a 15-.

Does the tinkerer need it? Well, more than the expert, as a 12- is quite a bit better than an 11-.

Will it help the guy with no skill at all? Not really, a 6- is not much more likely than a 5-.

I will note that this assumes a normal difficulty task.

 

if you allow for a -4 modifier (for a difficult task, or a penalty perhaps for lacking proper tools and so forth) then your owner's guide helps in decreasing order the expert more, the average guy next and the rookie the least.

 

it does not map to skill level in a reliable way. It maps to "chance of success" which makes it vary by both skill and difficulty.

 

BTW, IMX, most manuals are written and are very helpful to the novice, have some wasted stuff for the moderate guy, and little use to the expert.

[Hugh Neilson]

Re: Using d20 instead of 3d6 (DON'T KILL ME!)

 

IMO, the bell curve exactly replicates my expectations when it comes to adding modifiers.

 

Let's consider skills. You have an expert mechanic, a tinkerer and someone with no training at all. (15-, 11-, no roll, but the GM is being kind and giving him a 5-)

 

They need to perform some sort of repair and the GM rules that having the vehicle's owner's guide is worth a +1.

 

Does the expert really need it? No, a 16- is not that much better than a 15-.

Does the tinkerer need it? Well, more than the expert, as a 12- is quite a bit better than an 11-.

Will it help the guy with no skill at all? Not really, a 6- is not much more likely than a 5-.

 

A lot of this is semantics. To illustrate:

 

Let's move this to a d20 scale. We'll give +2 for the manual (increasing chance of success by 10%). Our people have +15, +10 and +5 to begin with, and you need a 20 to succeed.

 

Our expert mechanic will succeed without the book 80% of the tme - he needs to roll a 5+. He'll succeed 90% of the time with the book, so he only fails half as often. Cutting failures by half seems pretty significant. His chances of success are only increased by 12.5%, though (10%/80%).

 

Our novice succeeds half the time with no book, and 60% with his book. His failure rate has gone down by 20%, from 5 in 10 to 4 in 10. His success rate has risen 20%, by the same logic.

 

Our poor "DIY Guy" would have failed 70% of the time before, succeeding only 30% of the time. Now, he succeeds 40% of the time, a full 1/3 increase, and fails 60% of the time, a decrease of 1/7.

 

So a +2 bonus (flat 10% across the board) can also be viewed as:

 

Reducing Failure Increasing Success

50% 12.5%

 

20% 20%

 

14.3% 33 1/3%

 

A similar result will occur on the bell curve, of course. The better you are, the more a bonus reduces the odds of failure, but the less it increases the odds of success.

 

Point? That "flat bonus" will have more meaning to some characters than others no matter what you choose to roll. For me, the system isn't broken so why fix it?

[arcady]

Re: Using d20 instead of 3d6 (DON'T KILL ME!)

 

The bell curve nature of Hero makes it a lot less -random- of a system than d20.

 

On a d20, a roll of 1 is just as likely as a 14 or a 20. The values of your skills thus take a lot longer to have a degree of meaningfull impact.

 

+2 in d20 is similar to an 8- in Hero. An 11- in Hero is about the equivalent of +9 in d20.

 

I'm working that off of the average d20 DC being 15 or 20 - essentially 17.5.

 

Without a curve, most of the time the die roll will be the deciding factor, not your aptitude with the task. DnD players have to work to line up circumstance more (get modifiers) or even eliminate the roll (take 10 or 20). Hero players have more control over their ability - and their character will herself play the decisive role in the roll.

 

 

You can change to a d20, but it will completely alter the nature of the game and you should consider the implications carefully and be sure you like them first.

[Dust Raven]

Re: Using d20 instead of 3d6 (DON'T KILL ME!)

 

You seem to be implying that the 3d6 makes this happen.

 

Novice OCV +4

Veteran OCV +8 (thru skill levels or whatever)

 

Both shoot at Novice (DCV 4) at range of 25m. (+4 DCV)

Both are handed +1 accuracy Bow.

 

Novice gains 9.7% (hitting on 21 more chances in 216)

Veteran gains 11.6% (hitting 25 more times in 216.)

Oh, I forgot to cover this in my post, thanks Tesuji!

 

What we have here is an example of how the more experience/skilled veteran can make better use of an edge in difficult situations.

 

But of course, it's not an abolutely perfect system, but it's close.

[PhilFleischmann]

Re: Using d20 instead of 3d6 (DON'T KILL ME!)

 

You might find this interesting to note as well:

 

There is an official D&D book, Unearthed Arcana, published by WotC themselves, in which an optional system of using 3d6 instead of d20 is presented.

 

I found it quite eerie that there were so many HERO-ifications of D&D in that book: How to change from squares to hexes, disads, STUN, DEF, reputation, contacts, etc.

[vivsavage]

Re: Using d20 instead of 3d6 (DON'T KILL ME!)

 

The bell curve nature of Hero makes it a lot less -random- of a system than d20.

 

On a d20, a roll of 1 is just as likely as a 14 or a 20. The values of your skills thus take a lot longer to have a degree of meaningfull impact.

 

+2 in d20 is similar to an 8- in Hero. An 11- in Hero is about the equivalent of +9 in d20.

 

I'm working that off of the average d20 DC being 15 or 20 - essentially 17.5.

 

Without a curve, most of the time the die roll will be the deciding factor, not your aptitude with the task. DnD players have to work to line up circumstance more (get modifiers) or even eliminate the roll (take 10 or 20). Hero players have more control over their ability - and their character will herself play the decisive role in the roll.

 

 

You can change to a d20, but it will completely alter the nature of the game and you should consider the implications carefully and be sure you like them first.

You're talking about DCs and other things that indicate you think I'm suggesting making HERO into a d20/D&D/OGL thing. All I'm suggesting is keeping the EXACT same HERO mechanics and using a twenty sided die instead of 3d6 in order to make modifiers more consistent. I'm very aware of the benefits of the bell curve -- I prefer it over linear results except for the modifiers issue. But I'm definately not communicating my thoughts very well because most people seem to equate using a twenty sided die with the d20 *system*, which is not at all what I'm talking about. You can use a twenty sided die and not have anything to do with the d20/D&D/OGL rules.

[vivsavage]

Re: Using d20 instead of 3d6 (DON'T KILL ME!)

 

All of this maps perfectly to my expectations of what a '+1' ought to be worth in different situations. It should have little to no effect in the extremes and quite a large effect in those iffy 50-50 cases.

 

I don't see a problem with the existing system.

 

$0.02

I like this line of thinking! Let me do some more math and maybe I'll change my mind after all...

 

Okay, the +1 bonus bumps the no-skill guy from 5 to 6, or an improvement of 2%.

 

The average guy goes from 11 to 12, or an improvement of 12%.

 

The skilled guy goes from 15 to 16, or an improvement of 2%.

 

If you're inclined to believe that modifiers should affect the guy with the average skill the most...this might be pretty good after all!

[Zeropoint]

Re: Using d20 instead of 3d6 (DON'T KILL ME!)

 

First, I DO agree that modifiers should have more impact when near the 50/50 mark. It reflects my experiences in life: if a task is so difficult that failure is very nearly certian, making it slightly harder or easier isn't going to change things much. Likewise, if a task is trivially easy, making it slightly harder or easier isn't going to make much diference. It's those times in the middle, when something is hard, and your full concentration is required, when it's tough, but you think you can do it if everything goes smoothly, THAT is when your odds of success can be shifted greatly by little things.

 

Second, the randomness issue. In real life, my experience is that most people perform at a fairly consistent level of ability most of the time. In other words, knowing a person's skill, and the approximate difficulty of the task, we can make pretty good predictions as to whether they will succeed. The 3d6 roll reflects this--the rolls will cluster around the middle of the range, and characters will get average results most of the time. With a single die, as in d20, you are just as likely to perform spectacularly well or spectacularly poorly as you are to perform near your skill level.

 

Lastly, in connection with the randomness, is the fact that a d20 will yield a critical result 10% of the time, which is just too often. Consider: no matter how good you are, no matter how skilled in the arts of defense, no matter what armor or protective items you may have, the weakest and least skilled opponent you can find will still hit you one out of every twenty attempts. Likewise, you will fail at any task, no matter how easy, no matter your skill, one out of every twenty times.

 

That's just not right.

 

Zeropoint

[arcady]

Re: Using d20 instead of 3d6 (DON'T KILL ME!)

 

You're talking about DCs and other things that indicate you think I'm suggesting making HERO into a d20/D&D/OGL thing. All I'm suggesting is keeping the EXACT same HERO mechanics and using a twenty sided die instead of 3d6 in order to make modifiers more consistent. I'm very aware of the benefits of the bell curve -- I prefer it over linear results except for the modifiers issue. But I'm definately not communicating my thoughts very well because most people seem to equate using a twenty sided die with the d20 *system*' date=' which is not at all what I'm talking about. You can use a twenty sided die and not have anything to do with the d20/D&D/OGL rules.[/quote']The parallel of the d20 system is there as it illustrates what will happen in terms of the random nature of things if you just slot out 3d6 and slot in 1d20.