BRP Using a d20?

[Zenith Comics Presents...]

I know Pendragon does, and certainly the math is easy to adjust for that, it does reduce the granularity to be sure, but ultimately has anyone changed the d100 primary mechanic to a d20 one?

I see potential with in it, and certainly as I like to call my house engine "Bastard Sword", there is a certain amount of not puritan nature to my view of games, but I am curious if anyone has done this and if there are any pitfalls or triumphs to be shared from that experience?

[Hteph]

In the Swedish (old,old,old) version of BRP - Drakar och Demoner, they did this between 1st and 2nd edition, so this was the how I learned to play it from the start.  The two reason for keeping the % scale is better granularity for skill increase, and that people coming new to the hobby have it a bit easier to start with with percentage skill it seems.

Aside for that I saw little differences in actual play.

[Zenith Comics Presents...]

1 hour ago, Hteph said:

In the Swedish (old,old,old) version of BRP - Drakar och Demoner, they did this between 1st and 2nd edition, so this was the how I learned to play it from the start.  The two reason for keeping the % scale is better granularity for skill increase, and that people coming new to the hobby have it a bit easier to start with with percentage skill it seems.

Aside for that I saw little differences in actual play.

Thank you for sharing!

Slightly off topic, I love how Europe embraced BRP in a way North America never did and how Call of Cthulhu is the top RPG in Japan!

Cheers!

[Mugen]

On 2/4/2021 at 9:18 PM, Zenith Comics Presents... said:

Thank you for sharing!

Slightly off topic, I love how Europe embraced BRP in a way North America never did and how Call of Cthulhu is the top RPG in Japan!

Cheers!

Well, Sweden is not Europe.

In France, D&D is still the most popular game. Even though Call of Cthulhu is popular enough that it became a meme as the go-to generic game ("Tu prends Cthulhu et tu adaptes").

Concerning the use of a d20 in a BRP game, a possible problem I see is with critical successes. Pendragon and (Hero)Quest(World) consider a uniform 5% crit chance when your skill is under 20. It means the lower your skill, the more likely you are that a success is a crit. That is, with a skill of 10, 1 success out of 10 will be a crit, whereas with a skill of 1 every success will be a crit.

Edited February 11, 2021 by Mugen

[Singemonkey]

I'm really interested in this. I like the idea of all the numbers in the game being on the same scale, conceptually. And I also like the simplified arithmetic that can potentially speed up decision making in play.

Now CoC 7e solved the scale problem to an extent by bringing the stats into line with D100. But hitpoints for humans, for example, remain in the realms of the D20. I think the simpler solution is to bring all the mechanics back into the D20 range. Keep the 3D6 basic stats and the relative hit points and such, but divide all the percentile chances by 5.

I played a bit with the idea of rolling high, rather than rolling low. But the calculation for the equivalent target to hit are simply a headache. You could use tables but no one needs that. The benefits of getting regular players of D20 based games to more easily know what they're rolling are outweighed by the extra costs of determining the different difficulty levels needed to succeed.

It's very simple to use a D20 for percentile rolls with all skills scaled accordingly, and to roll low. 60% chance to hit, 30% hard, 15% extreme (or variations depending on the system) becomes 12, 6, 3 - roll under on a D20. Every +5% bonus or penalty is a +1 or -1. Every successful skill increase results in a +1.

Bonus or penalty dice approach simply works as in DnD 5e - except take the lower rather than the higher roll or vice versa if penalty.

Ultimately the difference is small and mostly one of feel since, even if the arithmetic is slightly easier, it's no like adding any two double digits is all that taxing. But i can make things a little easier, especially for calculating halves and quarters (etc.) on the fly (and no annoying +23% bonuses to juggle in your head to slow down the pace of a dramatic scene). And I like the conceptual aesthetic of bringing everything onto a similar numeric range within the mechanics - your character has a CON of 15, HP of 15 probably, and her skill with a battleaxe is 11.

WRT critical success, it's a very fair point. I think you just have to abandon the idea of giving people creeping extra percentiles as their skill goes up OR include a second dice roll on a roll of 20. Not ideal. It is the biggest problem with converting to D20.

I'll reiterate, I think the difference is small, but it could create a little bit of a smoother play experience that I'd like to try out.

Edited March 20, 2021 by Singemonkey
Didn't engage with an important earlier argument in a post

[Zenith Comics Presents...]

 

Sorry for the late replies, got distracted by work and by my HEROIC RPG project.

On 2/11/2021 at 8:54 AM, Mugen said:

Well, Sweden is not Europe.

In France, D&D is still the most popular game. Even though Call of Cthulhu is popular enough that it became a meme as the go-to generic game ("Tu prends Cthulhu et tu adaptes").

Concerning the use of a d20 in a BRP game, a possible problem I see is with critical successes. Pendragon and (Hero)Quest(World) consider a uniform 5% crit chance when your skill is under 20. It means the lower your skill, the more likely you are that a success is a crit. That is, with a skill of 10, 1 success out of 10 will be a crit, whereas with a skill of 1 every success will be a crit.

Yes I am aware that Sweden is not Europe lol

But up until 5e, BRP was more popular in most European nations than D&D, at least anecdotally. ;) 

The quote about Cthulhu also explains the preponderance of dark fantasy rpgs that come out of Europe as well methinks ;) 

17 minutes ago, Singemonkey said:

I'm really interested in this. I like the idea of all the numbers in the game being on the same scale, conceptually. And I also like the simplified arithmetic that can potentially speed up decision making in play.

<<SNIP>>

I'll reiterate, I think the difference is small, but it could create a little bit of a smoother play experience that I'd like to try out.

You know I had all but given up on this and then your post got me excited. I believe I will give this a try in my next campaign. :) 

Cheers!

[AndreJarosch]

On 2/4/2021 at 9:18 PM, Zenith Comics Presents... said:

Thank you for sharing!

Slightly off topic, I love how Europe embraced BRP in a way North America never did and how Call of Cthulhu is the top RPG in Japan!

Cheers!

In Germany:
Stormbringer was published from 1989 to 1992 with 5 supplements. 
RuneQuest 3 was published 1991 to 1995 with 5 supplements. 
RuneQuest 6 was published in 2015 and continues to be supported in its MYTHRAS transformation, but is published by a gaming club in VERY low print runs. 

BRP never made it into german. 

In germany BRP is only a footnote so far (except for Call of Cthulhu, first published in 1986 in german, which is HUGE in germany). 

We, the BRP/D100 fans, hope that this will change with RQG being published in german later this year. 

Edited March 21, 2021 by AndreJarosch

[Mugen]

21 hours ago, Zenith Comics Presents... said:

But up until 5e, BRP was more popular in most European nations than D&D, at least anecdotally. 😉

The quote about Cthulhu also explains the preponderance of dark fantasy rpgs that come out of Europe as well methinks 😉

My gut feeling concerning France is that D&D has always been the number one game in terms of number of players and sales, and by a large margin (except perhaps during the 4th edition days), and CoC second.

I think that a reason for this success and the lack of a national equivalent to Drakkar or Demoner or Das Schwarz Auge is that in the early 80s, D&D was considered by many as "the true game", and other equivalent games only as ersatz. DSA was rather successful, having 2 competing editions, one for toy stores and the other for book shops, but national equivalents like L'Utlime Épreuve were often overlooked.

[Lloyd Dupont]

With BRP skill increase is more granular. But having 50% in a skill and missing half of the time seems stupid some times... (hence more easy roll, i.e. skill% x2) should be used!

With D20 I like how you can +1 here and +1 there and roll each skill against each other in more meaningful fashion....

However every time I considered converting skill to a 1-20 range.. I gave up on the idea, feels ugly for some reason.. Not a mathematical reason , just some sort of uncomfortable feeling...

[Zenith Comics Presents...]

While I am sure there will be potential for a country-by-country break down of BRP in the history of Europe, I will concede the point that perhaps it was over represented by fans in the 80's and 90's as to it's popularity there. Something that has always been a way to claim "elitism" or "cachet" in North America from my youth was for folks to claim the much-more sophisticated and thereby intelligent Europeans embraced the item over us ignorant and commercialized North Americans. So moving forward, I stand corrected, and ultimately don't care what the numbers for Sweden, Belgium, the Netherlands, and remaining parts of the EU are. 😉

Back to the topic at hand my Europeers? 😄

[albesias]

10 hours ago, Lloyd Dupont said:

But having 50% in a skill and missing half of the time seems stupid some times... (hence more easy roll, i.e. skill% x2) should be used

A level 1 d&d character with proeficency in athletics and STR 14 for example, against a CD 15 has  a 50% 

[lawrence.whitaker]

Quote

With BRP skill increase is more granular. But having 50% in a skill and missing half of the time seems stupid some times... (hence more easy roll, i.e. skill% x2) should be used!

It probably bears repeating that most iterations of BRP stress that you only need to roll in dramatic or tense circumstances. Normal, standard, typical, everyday exercise of a skill is an automatic success: no roll needed, because the circumstances are favourable, no pressures, time constraints, threats or deadlines. It's only when such things come into play does the skill value take on dramatic meaning, and those who aren't quite as skilled as others start to feel the pressure.

Practical example: Lewis Hamilton = Drive 115%. Joe Everyman Drive 50%. Both characters drive the shops to buy a carton of milk. No need to roll Drive skill. Suddenly, both find themselves in a road chase as Bad Guys strive to get them. Now the Drive roll is important, and Lewis, with his Formula 1 expertise is going to come out of this potentially far better than Joe Everyman. But for simple, work-a-day tasks, the 115/50 difference between the two means nothing. It should only be when circumstances demand the dice be rolled should one start considering what your score in the skill means. And a good GM will apply modifiers to make the skill roll easier or harder, depending on those circumstances.

[MacDhomnuill]

I am going to do this so I can move my kids campaign off of DND 5e and onto Mythras, they are comfortable with the d20 mechanics so it will ease the transition. The conversion is simple for the most part (divide all % by 5and done) but I am pretty new to Mythras so I do want to say its going to be easy.

[Questbird]

On 2/5/2021 at 2:44 AM, Zenith Comics Presents... said:

I know Pendragon does, and certainly the math is easy to adjust for that, it does reduce the granularity to be sure, but ultimately has anyone changed the d100 primary mechanic to a d20 one?

I see potential with in it, and certainly as I like to call my house engine "Bastard Sword", there is a certain amount of not puritan nature to my view of games, but I am curious if anyone has done this and if there are any pitfalls or triumphs to be shared from that experience?

 

Check out Fire and Sword 

By one of Runequest's original designers RayTurney. It has many interesting ideas including using the d20, hitpointless combat, abstracted cost-of-living and ways to track reputation and favours with different organisations. I learned a lot from reading Mr Turney's design notes for the game.

[Mugen]

15 hours ago, albesias said:

A level 1 d&d character with proeficency in athletics and STR 14 for example, against a CD 15 has  a 50% 

But you're speaking of a game that was specifically designed with the idea in mind that skilled characters should not overshadow average, unskilled characters, unless they're from the rogue or bard class. At level 20, a maximized non-rogue character is going to have 55% more chance of success than an untrained character with ability 10. Quite like if in BRP only "rogues" could go over 80 with a skill with a base of 25.

[rules lawyer]

On 3/21/2021 at 7:01 AM, Lloyd Dupont said:

With BRP skill increase is more granular. But having 50% in a skill and missing half of the time seems stupid some times... (hence more easy roll, i.e. skill% x2) should be used!

With D20 I like how you can +1 here and +1 there and roll each skill against each other in more meaningful fashion....

However every time I considered converting skill to a 1-20 range.. I gave up on the idea, feels ugly for some reason.. Not a mathematical reason , just some sort of uncomfortable feeling...

Hi Lloyd, hope you're doing well.

1. Unless under duress there's no reason to roll anything.  Combat is by definition under duress so lets' assume your statement was only related to combat.
2. One would hope that most players would have a combat skill around 75% in games where combat is common and core skills in that area for things that mattered to their character's concept.  If they fail at 50% it's because they didn't really train much in that particular area but they're competent enough to be a secondary combatant.

Considering that a skill increase can be by multiple percentage points if successful there's very little difference between a D20 and D100.  +1 is 5%, but I've seen increases of 3% and such pretty regularly so the difference is trivial over a campaign save in very specific unlucky moments.  I find that players tell me that BRP feels more "swingy" than the WoTC D20 implementations due to regular advantage/disadvantage/bonus stacks and those bonus stacks are the real difference I think.

That said, there are plenty of rules and modifiers to simulate the bonus stacks if people want to accomplish that.  However; I do think that the rules are not as accessible to make this as comfortable as you'd like if you're not thinking like BRP and you come to it via other games.  If I need to look up how a character is affected by drunkenness in D&D I can google 5e, drunk and find that most of the content is house-ruled so I can easily come up with my own stuff and not be assailed by players.  If I try to do that in BRP, it's more of a slog to figure out as the google fu doesn't help as much due to popularity; and then in order to find the actual penalties I go to the addiction section of the yellow book and find that alcohol is mentioned as one of a few intoxicants and I can choose to apply anything from a -5 to -20 for a character who is drunk on any task they could attempt.

So we're left with wanting to use D20 to simplify things, but without effort it really doesn't simplify anything or make the game feel different.

[Lloyd Dupont]

Alright, lets put it an other way.

Even if someone has only 40% with spear, it does not ring true that they will simply "just miss" (60% of the time), it feels like the enemy defense is what make the attack fails.

And D20+Attack Scor vs Defense Score + 10 or D20 feels right here....

But granted what I think they do in CoC7 (read the combat rules only once, basically opposed skill rule, highest rule win in case of same degrees of success) seems mathematically equivalent but, perhaps for lack of practice, doesn't feel the same when I read it...
In fact I kinda tested it, I had a fantasy game early last year where highest roll got a tie breaker advantage, (RevolutionD100 rules) and this didn't feel right to me.. although I didn't ask my players their feeling on that particular point, maybe it was just me! ^_^ 

Edited March 23, 2021 by Lloyd Dupont

[threedeesix]

On 3/21/2021 at 7:12 PM, lawrence.whitaker said:

It probably bears repeating that most iterations of BRP stress that you only need to roll in dramatic or tense circumstances. Normal, standard, typical, everyday exercise of a skill is an automatic success: no roll needed, because the circumstances are favourable, no pressures, time constraints, threats or deadlines. It's only when such things come into play does the skill value take on dramatic meaning, and those who aren't quite as skilled as others start to feel the pressure.

Practical example: Lewis Hamilton = Drive 115%. Joe Everyman Drive 50%. Both characters drive the shops to buy a carton of milk. No need to roll Drive skill. Suddenly, both find themselves in a road chase as Bad Guys strive to get them. Now the Drive roll is important, and Lewis, with his Formula 1 expertise is going to come out of this potentially far better than Joe Everyman. But for simple, work-a-day tasks, the 115/50 difference between the two means nothing. It should only be when circumstances demand the dice be rolled should one start considering what your score in the skill means. And a good GM will apply modifiers to make the skill roll easier or harder, depending on those circumstances.

You beat me to it Lawrence. I was going to mention "who would ever get on a plane if the pilot with a 90% pilot skill had a 10% chance of crashing every time he took off or landed." 

[Mugen]

11 hours ago, Lloyd Dupont said:

Alright, lets put it an other way.

Even if someone has only 40% with spear, it does not ring true that they will simply "just miss" (60% of the time), it feels like the enemy defense is what make the attack fails.

And D20+Attack Scor vs Defense Score + 10 or D20 feels right here....

But granted what I think they do in CoC7 (read the combat rules only once, basically opposed skill rule, highest rule win in case of same degrees of success) seems mathematically equivalent but, perhaps for lack of practice, doesn't feel the same when I read it...
In fact I kinda tested it, I had a fantasy game early last year where highest roll got a tie breaker advantage, (RevolutionD100 rules) and this didn't feel right to me.. although I didn't ask my players their feeling on that particular point, maybe it was just me! ^_^ 

I don't remember how CoC7 works, but I'm personally in favor of letting the highest roll win if both protagonists fail their roll in a skill opposition.

Warhammer 4th edition does this, but it uses margin of success, and not straight reading of the roll. That is, if you rolled 30 and your skill is 47, your MoS is 1. If you rolled 63, it's -2. If your opponent had a skill of 50 and rolled 60 (MoS -1), you' d beat him if you rolled 30 and he'd beat you if you rolled 63.

From a mathematical point of view, there's not much difference between this and the "roll under your skill, but as close as your skill as possible" approach, if the highest roll also wins in a double failure case. But it requires less subtractions.

So, you have to chose between a quick and easy but counter-intuitive method, or a clunky but intuitive method.

Or you can re-work the game to make it roll-over, using d20+skill instead. Skill oppositions will be simple and intuitive.

[Zit]

Regarding crits, an old French RPG mixing percentiles for proficiency and d20 for "to hit" scores (Légendes) used the following : if you rolled 1 on d20, you rolled again if if you got a success, this was a crit.

[Lloyd Dupont]

I had this game, I played it a couple of times, quite like it.. 🙂 
Can't find anymore! 😮

[Mugen]

1 hour ago, Zit said:

Regarding crits, an old French RPG mixing percentiles for proficiency and d20 for "to hit" scores (Légendes) used the following : if you rolled 1 on d20, you rolled again if if you got a success, this was a crit.

Just to clarify : the percentiles/d20 divide worked like in Bushido (and other FGU games, I guess). You never rolled a d100, the percentile value was just here to record experience.

It's also a game that used Margins of Success, by the way. I remember that in its second edition ("Premières Légendes Celtiques"), the MoS of the confirmation roll was added to the first.

D&D3.X also had "confirmation rolls" on a 20, but it disappeared in 4th and 5th editions.

Edited March 23, 2021 by Mugen

[Singemonkey]

On 3/23/2021 at 11:06 AM, Zit said:

Regarding crits, an old French RPG mixing percentiles for proficiency and d20 for "to hit" scores (Légendes) used the following : if you rolled 1 on d20, you rolled again if if you got a success, this was a crit.

I really like this because it factors your skill into your chance to crit so that, even though you have to make a second roll, there's no esoteric calculation needed. This seems like a really good fix short of figuring a way to work it in a single roll. This is the missing piece that says I'm going to go ahead and flesh out a simple D20 version of BRP for the game I have in mind.

You can obviously do the same with a low roll - where your second roll on a natural 1 is a fumble if it fails against your skill.

 

[Mugen]

21 hours ago, Singemonkey said:

I really like this because it factors your skill into your chance to crit so that, even though you have to make a second roll, there's no esoteric calculation needed. This seems like a really good fix short of figuring a way to work it in a single roll. This is the missing piece that says I'm going to go ahead and flesh out a simple D20 version of BRP for the game I have in mind.

Yes.

A minor complaint I'd have is that I prefer crit chances to be 1/10th of your skill rather than 1/20th.

Of course, I can make crits happen if I roll a 1 or a 2, but it feels less natural than rolling under the 10s of a skill with a d100.

21 hours ago, Singemonkey said:

You can obviously do the same with a low roll - where your second roll on a natural 1 is a fumble if it fails against your skill.

I'd be more in favor of having fumbles when you roll a natural 20

Edited March 26, 2021 by Mugen

[Jaeger]

On 2/4/2021 at 7:44 AM, Zenith Comics Presents... said:

I know Pendragon does, and certainly the math is easy to adjust for that, it does reduce the granularity to be sure, but ultimately has anyone changed the d100 primary mechanic to a d20 one?

I see potential with in it, and certainly as I like to call my house engine "Bastard Sword", there is a certain amount of not puritan nature to my view of games, but I am curious if anyone has done this and if there are any pitfalls or triumphs to be shared from that experience?

 

There is really no reason not to in most BRP based games.

I recently did another read-through of my CoC7th rulebook. There is no reason not to divide by 5 and make it a d20 roll under game.

Insanity and advancement would have to tweaked a bit to work - but it is doable. Everything else could just be put on the 1-20 scale and no one at the table new to the game would notice the difference.

 

On 2/4/2021 at 11:03 AM, Hteph said:

In the Swedish (old,old,old) version of BRP - Drakar och Demoner, they did this between 1st and 2nd edition, so this was the how I learned to play it from the start.  The two reason for keeping the % scale is better granularity for skill increase, and that people coming new to the hobby have it a bit easier to start with with percentage skill it seems.

Aside for that I saw little differences in actual play.

This.

The granularity loss is theoretical at best. Concerns about crit rolls are theoretical at best.

In actual play, with the action flowing, nobody will notice.

You can even change the way advancement works to an XP points system that "levels" or allows you to buy points advancements. 

If converting to a d20 was that big of a deal when it comes to loss of granularity, then we would see lots of posts on the Pendragon forum asking to "improve" the game but upgrading it to a proper d100 scale. 

I looked. Couldn't find one.