How to determine difficulties

[taalyn]

I can't figure them out. They're beingtransparent. I have a huge excel file with all the odds and probabilities for my system, but have no idea how to decide what is "Hard" vs "Really difficult".

Anyone have helpful hints on how to go about figuring this out? (Saying, just fudge it is not helpful...I've tried already.)

Better yet, how did you determine difficulties for your games?

Aidan

[Steve Samson]

Hmm... I honestly haven't a clue what you are asking for. What exactly do you mean by "determining difficulties"? Do you want to create a list of tasks with modifiers as a GM resource? Is this for your own use in testing to see if the percentage of successes is reasonable? (Which leads to a need to determine what is "reasonable".) If you can be more specific with your question, it'd be easier to attempt an answer.

As far as what I am doing in my game, I personally hate interrupting a scene to look stuff up, so the design for my own game includes pseudo-modifiers (I don't use traditional modification mechanics, but that's a separate discussion entirely) for different difficulty levels, but I leave what difficulty to assign to what task entirely up to the GM.

Steve

[taalyn]

I mean, a guideline, which shows target numbers or somesuch.

I.e. At DL/TN 1, how often should the average character succeed? How often at DL/TN 5, or 10?

I want to make a chart as a GM tool, something like this:

Code Select Expand


DL           TN
Easy          1
Average       3
Medium        6
Difficult     9
.
.
.


so that s/he has some way to gauge what should be expected. But I want it fair and "realistic". I just have no idea what would be fair or realistic, especially when the difficulty increases.

Is that clearer?

[Jeph]

My method is drifting towards asking myself, "who can do it?" and then setting a TN or whatever so that that person has an 80% (or so, give or take 10 points) chance of success. I typically use the levels

Joe Schmoe
Beginner
Practiced
Expert
Master
Best in the World

For d20 (as a reference we all can relate to) i'd say that ranks as Schmoe DC 5, Beginner DC 10, Practiced DC 15, Expert DC 20, Master DC 25, and Best in the World DC 30.

--Jeff

[Jasper]

Jeph's approach is usually the one I take, and it's doubly useful for advice to players during character creation.  Additionally, I imagine how much I want players to be whiffing, and how much effort they should need to go through in order to stack the odds in their favor, for the whole game. This depends on what the characters are doing of course, and a lot on the flavor you're looking for.  In a superheroic game, I might prefer for heroes to fail a lot, since only really difficult things are worth testing them on anyway.  If you imagine a play session, how worried to players have to be about failing, after they've decided to have a character do something?

[orbsmatt]

In the end it really depends on the system.  If you are working with a d20 system, then the above idea mentioned by Jeph would work fine.  If you are working with a system that uses percentages, you would just have to work out the odds of something happening, and use that as a guide.

I think the real difficulty comes in deciding if a task is difficult or very difficult and giving the appropriate modifier.  However, that is completely up to the GM to figure out at the moment.

[Mike Holmes]

This is one of the most complex topics in all of RPG design potentially, but we've been through this before.

It sorta doesn't matter. That's hard to buy, but it's hard to explain what I mean. Basically, what are you trying to get out of the system? I mean, any reasonable percentages assigned to these monikers will be fine. I've seen Average mean that the task was 80% likely for the "average" character to accomplish, and I've seen it mean 5%. All depends on your POV of what these things mean. As such they're pretty pointless.

I propose to you that most GMs in play look at the character's ability level, and then pick a number that represents a task that's difficulty is based on one of the character's abilities. That is, let's say I want a tense scene with picking  lock. A TN = Ability results in 50% chance of success (your system does this, no?). So I consider the highest player's lockpicking rating of 5, and select a 6 rating for the lock - looking at the chart I then see that this makes it a "meduim" task. Which doesn't matter unless the player asks me for a description of the task.

Ron takes this to an sort of extreme in Sorcerer, and just says to rate the task in terms of how many more or less dice than you have that you should roll for the opposition. Thus a +1 task means that the opposition rolls one more die than you do no matter what your pool is.

Have you considered something like that? Brain's too fried to determine how that would affect your percentages. Works just fine for Sorcerer, tho.

If I have three blue motes, how do you describe that? Perhaps you should just match the expected value of a draw to the name for that level. Thus if you call three motes Average, and this tends to produce three "successes" then, yeah, I'd call 3 an Average difficutly. Putting things all on one scale, essentially, as then it's the same as working against an active opponent who has the same attribute.

How does that sound?

Mike

[taalyn]

Mike,

 Thant makes sense, and was mostly what I've been trying to do. The problem is that I am pisspoor at gauging the challenge of things I throw at the player.
 You also have to keep in mind that there are definitely actions that someone cannot do - a person with only one mote (because of minuses) will only ever get, at most 2 successes. The average joe will never get more than 10 successes, and will get 2 or 3 half the time.

 Since I've returned to having opposed and unopposed draws (it used to be that ALL tasks were drawn by the players), I now find I need an unopposed difficulty chart. I suppose I can try playing with it, and comparing it to opposed draws.

[Shreyas Sampat]

Here's an idea.
You could construct a "generic opposition caern" whose mote colours don't actually matter - you choose the target colour based on how strong the opposition is supposed to be (so there's a 1-mote colour, a 2-mote colour, and so forth). Then you don't have to do any actual math, just draw for the target colour you feel is appropriate.

[Mike Holmes]

Shreyas, in a previous discussion Aidan had pointed out why he wanted to go with just difficulties for "unopposed" rolls.

But there you have the major problem - tasks get out of range quickly.

What is the stat range like again? What does one mote represent, and what's a really high number of motes?

Mike

[taalyn]

A quick summary of the Crux mechanic:

 Players have various numbers of motes in their caern, ranging from a 4 mote minimum (except the Fate of course, of which there's only 1) to 9 or more. Most players will have 6 of each color.

 Players have Aspects (much like the traits of Over the Edge or Donjon). They will draw 3 default motes, and add in their Aspect. Based on the way chargen works, the average Aspect is at 2. So:

 Jo Schmoe: Aspect 0 (hand of 3)
 Average PC: 2 (hand of 5)
 Normal Max at chargen: 6 (hand of 9)
 Olympian: 8 (hand of 11) (can be done at chargen because of bonuses)
 Aspects of 9 or above are superhuman/heroic.

 Is that what you were looking for, Mike? I used that detail to create a DL chart, where 2 is the average DL, very difficult is 6, nigh impossible is 12.
There are levels in between those. Most of the time, I think DLs will be in the 2-4 range.

 Aidan

[Mike Holmes]

Is that what you were looking for, Mike? I used that detail to create a DL chart, where 2 is the average DL, very difficult is 6, nigh impossible is 12.

When drawing, you're looking only for the primary color, or are you using the "adjacent" thing? Basically, given an evenly distributed character with six motes of each color, what is he expected value per mote drawn? To keep it simple, ignore the draw out effect.

Do you know how to calculate an expected value? The average, basically.

Mike

[taalyn]

Using the adjacency rule as standard.

I don't think I know how to do the expected value. Is it the probability of drawing a value * value, for each color, all added together? I do know that 50% of the time, a player will get (3+aspect)/2 successes or better. Half the time, a player with an Aspect at 4 with get 3-4 successes.

Using a balanced Caern (6 of each color, 43 motes total, since all possible caerns averaged result in this one), there are 6 motes of a given target color (2 successes), and 12 of the appropriate adjacent colors (1 success). I'll search the web and see what I find, but if you can figure something out easy, or describe it, that would be great.

Edit: Looked it up, I was right. Now I'm going to go calculate it. DO I want it hand by hand, or all total? I'll do both, just in case.

Edit pt 2: Expected value wise, a single mote is worth 0.549 successes. The expected value for a hand of 3 (no Aspect) is 3 x 0.549, or 1.634 successes. Average joe (Aspect 2) gets 5 x 0.549, or 2.714.

So, does the bit of DL table I gave above look right?

Thanks,

A.

[Mike Holmes]

Edit pt 2: Expected value wise, a single mote is worth 0.549 successes. The expected value for a hand of 3 (no Aspect) is 3 x 0.549, or 1.634 successes. Average joe (Aspect 2) gets 5 x 0.549, or 2.714.

Well, Expected Value is what the gambler expects to get if he plays over and over again. So, if I expect to get 2.7 sucesses with a hand of 5, then that means that I'll expect to fail at the average task. Not by much, but it's the most likely result. Does that sound like what you want?

See, this is where the subjective part comes in. What's an "Average" task? One that you succeed at 50% of the time (that's a common definition). Or one that you succeed at 90% of the time - I mean we mostly succeed at most of the tasks we try.

Mike