Opposed rolls

[fmitchell]

Absolute lowest affects the odds compared to absolute highest and favors the lower skill.

Right. I just thought that was one of the options, especially considering HeroQuest adopts it. (The Mastery mechanic compensates somewhat, but it's still counterintuitive.)

Hence the Big-Endian vs. Little-Endian reference: if probabilities work out the same, I say choose the one that requires less thought. Yes, it's only one measly subtraction, and even those of us who are slow at arithmetic can manage it ... but it's one more mental step at the gaming table, when there are more important things to use brainpower on.

[Chaot]

Can we argue about something more relevant, like whether we crack open our morning eggs from the big end vs. the little end? (BTW, I like my eggs scrambled.)

But scrambling is far too complex and it slows down the morning egg routine. It can also necessitate an associated bowl and fork in order to blend yolk and white, as well as some milk to give it body and perhaps some chopped onion and ham for flavor. Whereas, if you go with a fried or over easy egg, it only entails the cracking and the dropping of the egg onto the heated pan and a flip to ensure that both sides are done.

Does anybody change their egg cracking habits at midday?

Midday crackings are undoubtedly hard boiled eggs, in which case, putting the egg in your palm and rolling it against a flat surface is the most efficient way to thoroughly crack the shell...

Wait, what were we talking about again...?

[badcat]

About how some people think you have to break the game to make an omelet.

[soltakss]

Yep. Harder than not doing so anyway. And it's unnecessary. Why must there always be a winner, immediately? Ties happen.

Sure. If you don't mind ties then just say that the same level of success has a tie.

What that means in practice, however, is open to interpretation. The classic "Hide vs Spot Hidden/Scan" means the Hider has successfully hidden and the Spotter has successfully made a Scan. Does this mean he is seen or not? With Opposed Rolls, you work out how well he has hidden and how well he has been seen and compare the result.

Same here. It's all about the feel. I think it's the way it'd spoil the immediacy of a 'Dramatic Moment' (slightly).

Depends on the game. Sometimes a few seconds working out if someone has succeeds increases the dramatic tension.

But a 90% attack will get past a 30% parry about (90x70=) 63% of the time. So the same numbers will give very different probabilities if you use opposed rolls. How can that be right?

Very easily.

First of all, Opposed Rolls are not the same as Attack/Parry rolls, so don't get the two confused.

A 90% skill has a better chance of scoring a critical or special than a 30% chance. So, it has a higher chance of winning an Opposed Contest using Levels of Success. Also, in the case of a tie, a 90% skill has more chance of making the roll by a higher margin than a 30% skill. The highest margin a 30% skill has of making a roll is 23% (a roll of 7) but a 90% skill has a highest margin of 71 (a roll of 19). In fact, any roll between 19 and 66 will beat the 30% skill on a normal success.

That's great - 'spot on'! All that's needed is a good interpretation of the tied situation, like this! Call it a draw?

The trouble is you can't always draw. Sometimes a draw makes no sense whatsoever. I suppose you could reroll on a draw but that might spoil the dramatic moment again.

[soltakss]

Some more concrete examples.

This shows the successes when just looking at Levels of Success.

Here, a critical beats a special beats a normal success beats a failure beats a fumble. If the same level of success is rolled by both parties, it is treated as a tie.

As always, the first result is the chance of Skill1 winning, the second is the chance of Skill2 winning. So, a 90% vs 30% contest will result in the 90% skill winning 68% of the time, the 30% skill winning 8% of the time and a tie the remaining time.

As a matter of interest, these are calculated by calculating the successes of every dice combination from (1,1) to (100,100) and then totalling the numbers of victories. It is better than using Probabilities as these are actual results.

Looking at these, you would have to reroll a lot of times or just accept that there would be a lot of ties.

10% vs 10% gives 13%/13%

10% vs 20% gives 12%/22%

10% vs 30% gives 11%/31%

10% vs 40% gives 9%/40%

10% vs 50% gives 8%/48%

10% vs 60% gives 7%/57%

10% vs 70% gives 6%/66%

10% vs 80% gives 4%/74%

10% vs 90% gives 3%/83%

20% vs 10% gives 22%/12%

20% vs 20% gives 20%/20%

20% vs 30% gives 18%/28%

20% vs 40% gives 16%/36%

20% vs 50% gives 14%/44%

20% vs 60% gives 12%/52%

20% vs 70% gives 10%/59%

20% vs 80% gives 7%/67%

20% vs 90% gives 6%/75%

30% vs 10% gives 31%/11%

30% vs 20% gives 28%/18%

30% vs 30% gives 25%/25%

30% vs 40% gives 22%/32%

30% vs 50% gives 20%/39%

30% vs 60% gives 16%/47%

30% vs 70% gives 14%/54%

30% vs 80% gives 11%/61%

30% vs 90% gives 8%/68%

40% vs 10% gives 40%/9%

40% vs 20% gives 36%/16%

40% vs 30% gives 32%/22%

40% vs 40% gives 28%/28%

40% vs 50% gives 25%/35%

40% vs 60% gives 21%/41%

40% vs 70% gives 18%/48%

40% vs 80% gives 14%/54%

40% vs 90% gives 11%/60%

50% vs 10% gives 48%/8%

50% vs 20% gives 44%/14%

50% vs 30% gives 39%/20%

50% vs 40% gives 35%/25%

50% vs 50% gives 31%/31%

50% vs 60% gives 26%/36%

50% vs 70% gives 22%/42%

50% vs 80% gives 17%/47%

50% vs 90% gives 13%/53%

60% vs 10% gives 57%/7%

60% vs 20% gives 52%/12%

60% vs 30% gives 47%/16%

60% vs 40% gives 41%/21%

60% vs 50% gives 36%/26%

60% vs 60% gives 31%/31%

60% vs 70% gives 26%/36%

60% vs 80% gives 20%/40%

60% vs 90% gives 15%/45%

70% vs 10% gives 66%/6%

70% vs 20% gives 59%/10%

70% vs 30% gives 54%/14%

70% vs 40% gives 48%/18%

70% vs 50% gives 42%/22%

70% vs 60% gives 36%/26%

70% vs 70% gives 30%/30%

70% vs 80% gives 24%/34%

70% vs 90% gives 18%/38%

80% vs 10% gives 74%/4%

80% vs 20% gives 67%/7%

80% vs 30% gives 61%/11%

80% vs 40% gives 54%/14%

80% vs 50% gives 47%/17%

80% vs 60% gives 40%/20%

80% vs 70% gives 34%/24%

80% vs 80% gives 27%/27%

80% vs 90% gives 20%/30%

90% vs 10% gives 83%/3%

90% vs 20% gives 75%/6%

90% vs 30% gives 68%/8%

90% vs 40% gives 60%/11%

90% vs 50% gives 53%/13%

90% vs 60% gives 45%/15%

90% vs 70% gives 38%/18%

90% vs 80% gives 30%/20%

90% vs 90% gives 23%/23%

[AikiGhost]

I think the "Hide/Spot duel" is the classic example that makes people perceive a need for opposed rolls.

In this situation you need to decide which is the active (IE: attacking skill) and the which is the defending skill, then err on the side of the defending skill when equal success levels are attained.

EG: Sneaking past a guard, attacker = sneaker, defender = guard

[Nightshade]

About how some people think you have to break the game to make an omelet.

More to the point, some people deny it breaks the game while others assert it. I don't think much is going to get done on that argument.

[Nightshade]

In this situation you need to decide which is the active (IE: attacking skill) and the which is the defending skill, then err on the side of the defending skill when equal success levels are attained.

EG: Sneaking past a guard, attacker = sneaker, defender = guard

The problem is its not clear which is which, and frankly, there's no absolute need to make the decision here. Doing so inevitably ends up favoring either people who use stealth or punishing them.

[Atgxtg]

The problem is its not clear which is which, and frankly, there's no absolute need to make the decision here. Doing so inevitably ends up favoring either people who use stealth or punishing them.

Unless you treat it like combat and give the sneaker some benefit, but reduce it for the successful "Parry" of the defender. For instace the sneaker isn't detected but either didn't get to move (and has to try again), or inly gets part of the distance before he has to duck behind cover.

That sort of thing happens all the time.

[frogspawner]

In this situation you need to decide which is the active (IE: attacking skill) and the which is the defending skill, then err on the side of the defending skill when equal success levels are attained.

The problem is its not clear which is which, and frankly, there's no absolute need to make the decision here. Doing so inevitably ends up favoring either people who use stealth or punishing them.

RQ3 (or was it 2?) said perception always beat stealth, I think (can't find the reference). However, I agree it's not always so clear-cut. I'd suggest deciding in favour of the status quo in any given situation, i.e. whoever stands to lose something (their pocket contents, their job as guard, their liberty, their life...) should have the advantage.

[Nightshade]

Unless you treat it like combat and give the sneaker some benefit, but reduce it for the successful "Parry" of the defender. For instace the sneaker isn't detected but either didn't get to move (and has to try again), or inly gets part of the distance before he has to duck behind cover.

That sort of thing happens all the time.

If more potentially opposed skills actually had degrees of results, I think you'd have an argument, but that's not the game we're actually dealing with here.

[Rurik]

Unless you treat it like combat and give the sneaker some benefit, but reduce it for the successful "Parry" of the defender. For instace the sneaker isn't detected but either didn't get to move (and has to try again), or inly gets part of the distance before he has to duck behind cover.

That sort of thing happens all the time.

That basically is just putting dramatic emphasis on the "Re-roll tied levels of success" approach - ultimately you just keep rolling until one side gets a clear victory (which can take a while if they both keep rolling normal successes or failures).

Not that this a problem, but I would think it would bog down the game more than just using the standard opposed roll rule as presented.

[Nightshade]

That basically is just putting dramatic emphasis on the "Re-roll tied levels of success" approach - ultimately you just keep rolling until one side gets a clear victory (which can take a while if they both keep rolling normal successes or failures).

Not that this a problem, but I would think it would bog down the game more than just using the standard opposed roll rule as presented.

It depends; if it means you have to keep trying and events progress, it could also add some nice dramatic tension. Of course that's always a case of one man's meat...

[Atgxtg]

It depends; if it means you have to keep trying and events progress, it could also add some nice dramatic tension. Of course that's always a case of one man's meat...

Exaclty. O could see someone throwing a stone across the yard to divert the guar's attention for the second try.

But it doe depend on if you want a simply pass/fail result or a degree of success result. I lean more towards the latter.

Oh, and pretty much any and every opposed skill can be set up with a degree of success. It is just that we tend to gloss over those "boring" tests to get to the "omportant" combat ones.

You could actually work up a debate as a series of Faslk Talk/Persuade/Oratory rolls with "attacks" and "parries" and have it do damage and beat down the opponent's resolve (say equal to POW points).

Would I want to do that all the time, no. But it would be a great bit for when the PCs get captured and have to convince the locals to spare their lives and not throw them to the volcano god.

[RMS]

Unless you treat it like combat and give the sneaker some benefit, but reduce it for the successful "Parry" of the defender. For instace the sneaker isn't detected but either didn't get to move (and has to try again), or inly gets part of the distance before he has to duck behind cover.

That sort of thing happens all the time.

I've tended to do exactly this. If there's a tie, I use it to build the tension a bit and allow characters to make a choice before proceeding. I don't try to immediately resolve it. In the case of stealth vs. perception, I use success vs. success or failure vs. failure to generally have the guard notice something but not be definitive, so there's still a chance to sneak past the guard but the guard is now on the lookout for something. Both characters can make a decision from here. The guard moves toward the hidden character to investigate, perhaps, so the tie gave him something, but the character still hasn't be conclusively observed, so can choose to sneak off, throw a rock to distract the guard, hide deeper in the shadows, cast a spell, jump the guard, etc.

I've never run into a problem with this interpretation, and if all else fails we can just reroll to see what happens. (Note: I never call for a reroll without allowing a change in actions, tactics, etc.)

I also do interpret the difference in success levels as a determination of how successful the opposed action was, frequently resulting in the winning side having some sort of advantage in the subsequent interactions. A big success of the guard or sneaking character results in a starting advantage in combat, or in sneaking through and leaving no trace to find later, etc.

I find using the highest-under roll inelegant in a very distasteful way, and while largest success is perfectly fine I just don't see the point in bothering with it. I like ties during the game like this. They add something to the game with tension and choices that I like.

[Lord Twig]

I have realized that I was over thinking things and the default method makes a bit more sense now.

So the way I understand it. First check level of success, Critical beats Special beats Success beats Failure beats Fumble. Then the loser, if successful can downgrade the winners success one level for every level of success achieved.

If both get the SAME level of success then highest roll wins. In this case you do NOT downgrade the success of the winner, which would result in a Failure every time.

Now for another problem I noticed. For skills over 100% the only benefit you are receiving is increasing your chance to Critical or Special. So if I have 200% vs. someone who has 100% then if we both succeed I can't roll over 100% so the extra 100% I have is not helping.

By contrast if you use the "roll low" method (a.k.a. "best margin") then if I roll a 85 vs. the other guys 30 the 200-85=115 beats 100-30=70.

[Atgxtg]

Now for another problem I noticed. For skills over 100% the only benefit you are receiving is increasing your chance to Critical or Special. So if I have 200% vs. someone who has 100% then if we both succeed I can't roll over 100% so the extra 100% I have is not helping.

By contrast if you use the "roll low" method (a.k.a. "best margin") then if I roll a 85 vs. the other guys 30 the 200-85=115 beats 100-30=70.

Yeah but the "margin" method makes it not worth rolling in cases like that. It pretty much become high skill wins unless low skill gets a crti or special.

I think that to some extent it all depends on just how you imagine very high skill levels. If you see things as a "mythic" linear progression as in Glorantha, then 200% is twice as good as 100%.

If you look at it with a more "realistic" view, then the standard method makes more sense. Generally in a fight between masters the difference between them is rather slight. And it will take a little while for that extra critical and special chances to make the difference.

[Rurik]

That is true, you need a way to deal with skills over a hundred when using high roll wins.

Simply halve both skills until they are both under 100... >:->

(NOT!)

The way MRQ deals with it (after two updates) is to add your skill over 100 to your roll to determine the winner of tied success levels. So if my skill is 140 and your skill is 120, and I roll a 72 and you roll an 85, my roll become 112 and your roll becomes 105 for purposes of deciding a winner.

At that point the "makes roll by most" method is almost as simple, though most people find addition easier than subtraction.

I used the makes roll by most method for a while as I am not afraid of simple subtraction (also known as "complex math" on various boards) - but must admit in the end I switched to just using highest roll wins as it seems simpler in practice at the table. It becomes second nature in short order.

[AikiGhost]

RQ3 (or was it 2?) said perception always beat stealth,

Thats my take on it too, Perception would be the defending skill, so like a parry against an attack a basic perception test should detect a basic success on a stealth test.

[Sven Norén]

I've never seen the sneak/spot situation as requiring opposed rolls, but that may be because I never upgraded from RQ2 to RQ3...

What I would do is ask for a straight roll from the sneaker. If he fails he can be spotted by anyone looking in the right direction. If he succeds it takes a succesful Spot roll to spot him, and if he scores a critical success it takes a critical Spot to discover him.

If you want skill levels over 100% to make a difference, then borrow from the (optional?) combat rules: Any attack percentage over 100% acts as a penalty to parry, such as if you attack with a skill of 120% then the defender gets a -20% penalty to his parry skill.

[Pete Nash]

I think that to some extent it all depends on just how you imagine very high skill levels. If you see things as a "mythic" linear progression as in Glorantha, then 200% is twice as good as 100%.

If you look at it with a more "realistic" view, then the standard method makes more sense. Generally in a fight between masters the difference between them is rather slight. And it will take a little while for that extra critical and special chances to make the difference.

This is definitely a matter of personal interpretation. My personal experience is that some masters are much better than others, and the difference between them (modeled as percentage skills) is nowhere near slight!

For example, you could place a newly made 1st dan black belt against a senior 7th dan of his martial art... Or a standard knight of the SCA versus one of the Super-dukes. These sort of bouts don't normally last much beyond a few blows. :shocked: Single combats normally only bog down between people of roughly equal skill.

So from my perspective the "realism" is that its the difference between the individual fighter's skills which counts... not the fact that they reached 100%. Thus I'm definitely a 'mythic linear' kind of guy and use a similar rule to the one Rurik mentions to preserve the skill difference in favour of the most skillful fighter.

(Sorry for using a fighting analogy here, but the trend should apply to most other things. E.g. A physics professor at a university vs. Einstein over a question of relativity. Both are masters of the subject, but I think I know who should win the overwhelming majority of debates... at least in the early 1900's! )

[Shaira]

So from my perspective the "realism" is that its the difference between the individual fighter's skills which counts... not the fact that they reached 100%. Thus I'm definitely a 'mythic linear' kind of guy and use a similar rule to the one Rurik mentions to preserve the skill difference in favour of the most skillful fighter.

Hi Pete, hi all,

I'm just dipping into this discussion from time to time - this bit has piqued my interest quite a bit.

Just to clarify - are you saying that if the winner (in the sense of biggest success margin where both attacker and parryer make their rolls) of an opposed combat roll is the attacker, the parry effectively fails? I'm asking as the default SB5 behaviour (I still haven't received my BRP copy!) is obviously that if both attacker and defender succeed, the parry or dodge takes precedence over the attack. Your suggestion would obviously go a heckuva long way to break the combat deadlock which would otherwise occur between your 1st and 7th dan fighters.

Cheers,

Sarah

[Nightshade]

This is definitely a matter of personal interpretation. My personal experience is that some masters are much better than others, and the difference between them (modeled as percentage skills) is nowhere near slight!

For example, you could place a newly made 1st dan black belt against a senior 7th dan of his martial art... Or a standard knight of the SCA versus one of the Super-dukes. These sort of bouts don't normally last much beyond a

However, that turns on assuming such people are, indeed masters. The fact they have certain titles attached to it does not mean they have reached 90% or better in skill in the sense the game uses them.

[Pete Nash]

Just to clarify - are you saying that if the winner (in the sense of biggest success margin where both attacker and parryer make their rolls) of an opposed combat roll is the attacker, the parry effectively fails? I'm asking as the default SB5 behaviour (I still haven't received my BRP copy!) is obviously that if both attacker and defender succeed, the parry or dodge takes precedence over the attack. Your suggestion would obviously go a heckuva long way to break the combat deadlock which would otherwise occur between your 1st and 7th dan fighters.

Effectively yes, whomever wins the opposed roll gains the advantage... But this is my own personal way of doing things. I like opposed rolls so much, I even wrote my own set of combat house-rules based on them, which can be found at the following link if you're interested. Unfortunately they are designed for use with MRQ rather than BRP, but the core opposed roll mechanic will translate cleanly between both systems.

http://mrqwiki.com/wiki/images/c/c0/Opposed_Roll_Combat_Rules_v2.4.pdf

They resolve the SB5 type combat deadlocks very effectively, and give a significant advantage to the higher skilled combatant, even when skills reach the hundreds. I like my combats to be short, deadly and spectacular! >:->

BRP (when you get it) uses a matrix of attack LOS vs. parry LOS which, just like SB5, gives precedence to the defender when ties occur. So despite the slightly increased chance of a critical result in BRP, it is still prone to deadlock situations.

[Pete Nash]

However, that turns on assuming such people are, indeed masters. The fact they have certain titles attached to it does not mean they have reached 90% or better in skill in the sense the game uses them.

Indeed. It is all a matter of semantics and interpretation. However, I personally consider anyone who achieves a 1st dan in an oriental martial art to be at least 90% in their skill, and I apply the same standard to an SCA knight or a Master in the European martial arts. Such titles are usually only applied to those who have shown (at the very least) an extremely high level of prowess, and the ability to consistently overcome their peers in competition.

I also use the same standard for educational awards too, i.e. a PhD for example.

Thus for me, these 'titles' are the vital anchor point to what otherwise is a completely abstract value. How else can you qualify what the skill percentage actually means?