What should I use: D20 vs D100, for my game?

[DreadDomain]

On 1/13/2024 at 4:01 PM, Mugen said:

BRP is also lacking a good skills opposition rule. Simply comparing levels of success results in too many ties.

Correct. The ties are not the problem. The fact that it results in too many ties is the problem. That is why I like to introduce Hard successes from CoC. Between, normal, hard, special and critical, it makes the success levels quite narrower and repeated ties less likely.

On 1/13/2024 at 4:01 PM, Mugen said:

And a tie, in a lot of situations, is in fact a success for one of the protagonists. For instance, if someone is hiding from another character, that person is alright if nothing happens.

Maybe, maybe not. In a hide and seek or stealth and watch situation means the situation is unresolved. The seeker has not found you yet but they are still looking in your area. Tension rises, time passes. Iis the hider under time pressure? Is the seeker?.  Will something happen to stop the search (from another player perhaps)? If not, roll again. A stealth roll is similar. The watcher did not spot the stealthee, but the later could not move.

But sometimes you do want a one roll resolution. 

On 1/13/2024 at 4:01 PM, Mugen said:

Even a solution like the one in Pendragon/Mythras system where you compare the d100/d20 results to break ties have flaws : it's counter-intuitive (as you have to roll low to get better success levels, but have to roll high to break ties) and still produce a lot of ties (as skill failure versus skill failure is not covered).

Personally, I don't find it counter-intuitive. After a tie on success level, you do have to ask yourself who roll the best. Wether the best means high or low is neither here nor there. But if it is counter-intuitive for your group, use lower roll wins. It will take the edge off the higher skill a bit but thet still have the edge. It also means that the higher skill always wins when they roll lower then the opposition.

On 1/13/2024 at 4:01 PM, Mugen said:

A simple solution is to use the formula behind the Resistance Table : 50+active skill-passive skill.

Yes, that too.

[Kloster]

13 hours ago, DreadDomain said:

The ties are not the problem. The fact that it results in too many ties is the problem.

I think the same.

13 hours ago, DreadDomain said:

That is why I like to introduce Hard successes from CoC. Between, normal, hard, special and critical, it makes the success levels quite narrower and repeated ties less likely.

I don't have CoC7 (I stopped with 5.5 and 6). What is this 'Hard success rule'?

[DreadDomain]

14 hours ago, Kloster said:

I think the same.

I don't have CoC7 (I stopped with 5.5 and 6). What is this 'Hard success rule'?

A Hard success is when you roll half of your skill value or below. 

[Renfield]

This discussion of Opposed rolls is SUPER helpful to me.   My game relies on Opposed rolls a bunch, and so everyone's experiences with this mechanic is much needed!

I was going to use the mechanic of "Each player rolls, highest roll under their Skill wins." 

- I don't see this creating hardly any Ties because a Tie would mean you both had the same Skill value and you both rolled the same value on the Die = uncommon result

- To me the phrase of "Each player rolls, highest roll under their Skill wins."  = very intuitive and easy and quick to me.  And requires no additional rolls.

 

p.s. My players and play tests with other non BRP groups = any time there are multiple sequential rolls = suuuper slow down game.  They debate if the rolls are correct, if needed, and the different targets or results needed for each roll.  SO, I am thinking of avoiding rules where the player has to roll, and then immediately roll again.  

One such case i recall in another game system was something to the effect of "roll your % in the activity, and then roll again in a specific skill under that activity"  and I think that may not be needed.

What do you think?

[Atgxtg]

On 1/14/2024 at 2:28 AM, DreadDomain said:

Correct. The ties are not the problem. The fact that it results in too many ties is the problem. That is why I like to introduce Hard successes from CoC. Between, normal, hard, special and critical, it makes the success levels quite narrower and repeated ties less likely.

One thing you could do is to have something that breaks ties. For instance higher skill wins on ties or lower tens die, or some such. 

 

I was working on a method of using the ones die to determine success level rather than math/table. For instance all crticals ended with a "1", all specials ended with a "2" and so forth. That way one a tie a 46 will beat any success than ended in a 7 or higher. That way ties only happened when both the success levels and the die rolls matched (1% of the time). 

 

[Mugen]

28 minutes ago, Atgxtg said:

One thing you could do is to have something that breaks ties. For instance higher skill wins on ties or lower tens die, or some such. 

Using higher skill is not really a good idea, as it gives a huge advantage to the higher skill even if it's only 1 point superior.

Say for instance you oppose a 100% skill versus a 99% one. The chance that the highest skill wins in this case depends on the number of success degrees you use, but it will be closer to 70 or 80% than 50%.

[Atgxtg]

35 minutes ago, Mugen said:

Using higher skill is not really a good idea, as it gives a huge advantage to the higher skill even if it's only 1 point superior.

I agree, I just pointed it out as an option.

35 minutes ago, Mugen said:

Say for instance you oppose a 100% skill versus a 99% one. The chance that the highest skill wins in this case depends on the number of success degrees you use, but it will be closer to 70 or 80% than 50%.

Yup. I

Ultimately this all comes down to RQ not being designed with opposed rolls in mind. It had Attack vs. Parry and the resistance table. It predated that by a few years.

[Kloster]

9 hours ago, DreadDomain said:

A Hard success is when you roll half of your skill value or below. 

Thanks. Good idea. I will add it as it reduce the number of ties (and thus reduce the number of substraction to perform).

[Mugen]

14 hours ago, Atgxtg said:

I agree, I just pointed it out as an option.

Yup. I

Ultimately this all comes down to RQ not being designed with opposed rolls in mind. It had Attack vs. Parry and the resistance table. It predated that by a few years.

There's also a rule for "Hide and Seek", which IIRC is : roll under (Stealth) skill, if successful subtract your skill from the (Perception) skill.

Edit: Resistance Table was, IMHO, a very elegant and efficient mechanism when it was designed. I'm liking the option of using its core concept as a basis for skill opposition more and more. Its drawback is that it lacks the possibility to have different effects with different levels of success.

12 hours ago, Kloster said:

Thanks. Good idea. I will add it as it reduce the number of ties (and thus reduce the number of substraction to perform).

Steve Perrin's Quest Rules used it as one of the 4 success thresholds, which were Skill, Skill/2, Skill/10, Skill/100 (obviously, the last one was only there for very high skills).

Edited January 16 by Mugen

[Atgxtg]

4 hours ago, Mugen said:

There's also a rule for "Hide and Seek", which IIRC is : roll under (Stealth) skill, if successful subtract your skill from the (Perception) skill.

Yup. I remember that from RQ2, I think.

4 hours ago, Mugen said:

Edit: Resistance Table was, IMHO, a very elegant and efficient mechanism when it was designed. I'm liking the option of using its core concept as a basis for skill opposition more and more. Its drawback is that it lacks the possibility to have different effects with different levels of success.

There was an article in Different Worlds which did just that. You could have different success levels, you'd just need to extend the specials for the passive side. 

But, ultimately Pendragon does the same thing in a more elegant fashion.

 

Oh, and on a related note, I was working on a solo RPG that used the resistance table, but in a hidden way. I made 50%-NPC skill a modifier to the PC's ability. So if the PC with Sword 70% and was facing a bandit with ax 60%, the PC would subtract 10% when fighting that bandit. If he later ran into a goblin with scimitar 30%, he'd add 20% to his skill. It was the resistance table.

Since I used the ones die to determine success level, I could determine who wins and the success level with one roll, which was very nice for a solo game. You also got a choice of specials to make solo combat more interesting.

 

 

4 hours ago, Mugen said:

Steve Perrin's Quest Rules used it as one of the 4 success thresholds, which were Skill, Skill/2, Skill/10, Skill/100 (obviously, the last one was only there for very high skills).

But could be scaled further on if needed. 

[Mugen]

1 hour ago, Atgxtg said:

Oh, and on a related note, I was working on a solo RPG that used the resistance table, but in a hidden way. I made 50%-NPC skill a modifier to the PC's ability. So if the PC with Sword 70% and was facing a bandit with ax 60%, the PC would subtract 10% when fighting that bandit. If he later ran into a goblin with scimitar 30%, he'd add 20% to his skill. It was the resistance table.

IIRC, Symbaroum works like this. Same for french game Brygandyne, which is an evolution of Warhammer.

D&D base d20 system is also not very different, with a d20 roll-over logic.

1 hour ago, Atgxtg said:

I remember that from RQ2, I think.

And me from RQ3. 🙂

[Atgxtg]

19 minutes ago, Mugen said:

IIRC, Symbaroum works like this. Same for french game Brygandyne, which is an evolution of Warhammer.

D&D base d20 system is also not very different, with a d20 roll-over logic.

No, it isn't. THe only real difference is that with each player rolling it turns into a 2d20 bell curve. 

19 minutes ago, Mugen said:

And me from RQ3. 🙂

Yup, there too. 

[Darrin Kelley]

The Golf-Ball Of Doom. Which I do own one of.

I find that the D100 itself is a lot more satisfying to roll than percentile dice.

[Mark Mohrfield]

On 1/16/2024 at 4:28 AM, Mugen said:

There's also a rule for "Hide and Seek", which IIRC is : roll under (Stealth) skill, if successful subtract your skill from the (Perception) skill.

Another approach would be to subtract the number rolled (if successful) from the perception check. Or, to preserve the lower is better trend, the difference between the successful roll and the skill level. .

[Mugen]

37 minutes ago, Mark Mohrfield said:

Another approach would be to subtract the number rolled (if successful) from the perception check. Or, to preserve the lower is better trend, the difference between the successful roll and the skill level. .

That method gives results that are very similar to roll under black jack or comparison of margins of success. So, I think it's better to not have a specific rule for hide and seek, and use a more generic skill opposition rule.

[Mark Mohrfield]

2 hours ago, Mugen said:

So, I think it's better to not have a specific rule for hide and seek, and use a more generic skill opposition rule.

Agreed.