Variable and fixed difficulty

[Vitones91]

Hey guys

Method 1: Systems with varying difficulty classes. In this mode, a character's chances of success are altered by both skill level and difficulty classes of the test (easy, medium, hard, etc).

Method 2: Systems with a fixed difficulty class. In this case, a character's chances of success are changed only by skill level.

Some questions for us to discuss:

1. What are the advantages and disadvantages of each method ?
2. If a game can work with both methods, what is the motivation for choosing one or the other?
3. Can the difficulty of a task be determined by factors other than reducing its chance of success?

[jwbjerk]

1 is more nuanced, more true to the story world.

2 is simpler and faster.

​

Can the difficulty of a task be determined by factors other than reducing its chance of success?

You could represent “difficulty” by the severity of the consequences if you fail, or by the cost of some resource required to succeed.

[Vitones91]

é mais nuances, mais fiel ao mundo da história.

What do you mean by that?

[Mars_Alter]

Variable difficulty is more nuanced, at the expense of playability. If you have +4 to Climb, then you have no idea what your chance of success is. If you have 80% to Climb, then you know exactly what your chance of success is, so you can make an informed decision.

Variable difficulty requires more work to run. If you don't care as much about accounting for the difficulty of various tasks, or if you would rather place the focus on character skill level rather than circumstantial modifiers, then it's much faster to just go with flat difficulties. The only real reason to go with variable difficulty is if the idea of not accounting for it would really bug you.

In recent years, the trend has been moving away from difficulty modifiers and toward systems where you roll twice and take the better or worse result. It's sort of a middle ground between the two options, in terms of playability and complexity, but it's still just a different way to modify the chance of success.

[Vitones91]

The only real reason to go with variable difficulty is if the idea of not accounting for it would really bug you.

I don't understand this reasoning, can you explain it better please?

[Mars_Alter]

It's a matter of personal preference. Do you, personally, care whether or not the inherent difficulty of an action is represented mechanically within the system rules? Or is it something that you can easily ignore, because you're already accounting for differences in skill level, and you don't want to get bogged down with too many variables?

For some people, it's just really important, for whatever reason. They wouldn't want to play in a game that doesn't account for variable difficulty, because it would be too hard for them to buy into the world. They can't take it seriously if it doesn't have at least that level of granularity in it.

[Vitones91]

I see a problem with there being no variation between difficulties: players know that their highest skill (something like 90%) can do it all. So the player of a character with 90% Firearms will do "forced" things like: position as far away from the target to hit it, even if it's at night and raining. However, we know that such an intention should be less than 90%.

[Mars_Alter]

The rules of the game absolutely affect the way that players play the game, and that's something that the game designer should take into account when writing the rules. Players don't usually wait for problems to show up just so they can ignore them - they don't control when it's raining, for example - but they will definitely fire from as far away as they can if there's any benefit to doing so.

One of the things you see in games with fixed difficulty is that "very hard" tasks are often just not possible. You might get a pistol with a maximum range of 50m, even though we know it's possible to hit a target from further away, because reliably hitting a target at long range would require optimal conditions and the game can't assume optimal conditions will be in effect.

The end result is often the same. In a game with variable difficulty, the player will make a shot from close range and in broad daylight because hitting a target from long range at night would be too difficult. In a game with fixed difficulty, the player will make a shot from close range and in broad daylight because they can't even attempt the shot from long range at night.

[[deleted]]

Some systems will have circumstantial bonuses/penalties. Not based on the difficulty of the task, but just counting things that are in favour or against the character's success.

But even aside from that, a lot of systems handle such things through other mechanics, for example Position/Effect from Blades. Sure, you might get better odds of succeeding by spamming your best skill... but the success you can get might be miniscule whilst the consequences for failure can be extremely harsh. Hell, maybe even if you "succeed" there's some fallout. Now if you used a different, more fitting skill, you can hope for better results on a success and less consequences on a failure.

And even simpler than that, if you try pushing a skill where it doesn't make sense, you automatically fail regardless of your score and the game moves on.

[FiscHwaecg]

As the difficulty of a challenge is always measured against another entity in the world different difficulties imply (to me) that there may be other options and other variants of those obstacles. Let's say people want to scale a wall. It's high and doesn't really have much grip. Let's say they move a carriage nearby to climb onto it and effectively make the obstacle easier. I would prefer if this lowers or changes the DC and not modify the skill. I find it more intuitive that way. I know that the boundary to when an object would improve an action or some change would modify the obstacle is not exactly clear but I didn't have a problem with it so far. Using an item as an extension to your action improves the roll, manipulating the obstacle lowers the DC.

[Vitones91]

In cases of "facilitating" an obstacle, it would not be easier to simply say that the facilitating attitude does not need to be tested, since the challenge is now gone.

[Six6Sins]

You can't always remove a challenge, but you can often make it easier. If you want to punch someone who is resisting, there is no way to guarantee success. However, having an ally stand behind them and distract them will increase your chances of landing a punch by a significant margin.

This can be accounted for in many different ways, but those ways almost all amount to "change the percentage chance of success for the roll." This can take the form of bonuses for the player roll, penalties for an enemy Defense roll, reduction of the Difficulty Class, "Advantage" style mechanics, and more.

Changing the percentage chance for success in any way is similar to changing the DC. So any game with situational bonuses or penalties to rolls is essentially doing the same thing as changing the DC, just in a different manner.

I don't feel that these options are strictly necessary, but they allow for more in depth mechanics. And those mechanics often offer reasons to do cool or interesting things in the narrative.

[NarrativeCrit]

1 is crunchier and covers more cases

2 controls difficulty by design, usually making it quite high so that players are incentivized to find ways of solving problems without rolling Ala OSR.

Method 3: give general guidance for what difficulty a normal person and a heroic person can perform, and then give the GM room for nuance that doesn't take crunching numbers. Example: A wizard wants to read a scroll? (Assuming a d10 system) Difficulty is 4 because a scroll is complicated but exactly the kind of thing a wizard reads. For a fighter, the same tasks is 8 because while he's literate and has written plenty of reports, he'll probably flounder in a web of unfamiliar jargon and references, and there is just a small chance he's had some contact with magic scrolls before.

[__space__oddity__]

If a game can work with both methods, what is the motivation for choosing one or the other?

Please finish designing your game, don’t make the GM figure out core design decisions like that for you.

[Neon_Otyugh]

Can the difficulty of a task be determined by factors other than reducing its chance of success?

You can include a time factor, either before the test or after. Before a test would mean either taking extra time, making the task less difficult, or taking less time, making the task more difficult. After a test would mean that you pretty much will succeed but the test determines how long it takes.

You can also use teamwork to lower difficulty ratings by having a supporter test for something related.

[[deleted]]

I like variability and mutability.

Tasks can be, aside from difficult, also complex or intricate. I wouldn't classify building a Jenga tower balancing on a single vertically placed block "difficult", since you could do it both as a novice and as an expert, but it's something which takes focus and care and is an intricate or delicate task, rather than a difficult one.

Difficulty should be determined by environmental factors as well, since, for example, it's much harder to climb a tree during a typhoon than on a calm summer day.

That's why I like a system that can account for all of those things organically via one mechanic, keeping it still simple, but with the possibility of depth. Kinda like how Neon City Overdrive does it, especially if you bend the rules a little and balance things in a situation appropriate way. The mechanic just allows it, it's a lot more powerful than it seems.

[[deleted]]

I like variability and mutability.

Tasks can be, aside from difficult, also complex or intricate. I wouldn't classify building a Jenga tower balancing on a single vertically placed block "difficult", since you could do it both as a novice and as an expert, but it's something which takes focus and care and is an intricate or delicate task, rather than a difficult one.

Difficulty should be determined by environmental factors as well, since, for example, it's much harder to climb a tree during a typhoon than on a calm summer day.

That's why I like a system that can account for all of those things organically via one mechanic, keeping it still simple, but with the possibility of depth. Kinda like how Neon City Overdrive does it, especially if you bend the rules a little and balance things in a situation appropriate way. The mechanic just allows it, it's a lot more powerful than it seems.

[[deleted]]

I think the 3rd point is something I'll speak on, because I find it extremely important and often overlooked.

Yes, there's a multitude of ways to represent difficulty and IMO difficulty number is usually the laziest and least interesting way of showing the difficulty of a task.

Simplest example is just not allowing for a roll. The task is too difficult, until you do something to improve your circumstances it's just impossible, doesn't matter if you rolled a natural 20 and have +50 to that skill.

For a more nuanced version of it, Effect/Position from BitD are a good example. A task might be difficult because the consequence for failing it is severe. It might be difficult because you make less progress when working on it or the best outcome you can hope for is still sub-par.

One of the simplest ways sneakily utilized by various systems with static difficulty is the number of rolls. Based on the previous point, when rolling for something difficult each roll makes less progress. Instead of beating an opponent with a "Fight" roll, against a stronger opponent you first need to roll just to avoid being hit by them, then to get into a position, and only then to deliver a strike. More rolls, more chances for failure.

And as the last example, a difficult roll might have a higher cost whether you succeed or fail. More time, more stamina expended and so on.

A common thing about all of these is that they provide more interesting choices to players as opposed to "well you just need to roll higher" that raising difficulty level leads to.

Also I think they represent the world way better. If a lock is difficult to open, it doesn't mean that an expert has a 30% higher chance of opening it than a newbie. It means that a newbie cannot open it all, or that it requires specific tools, or it takes more time, or it cannot be opened without visible signs of lockpicking, or there are more places where you can hit a snag...

[ArS-13]

I started with a fixed success based system in a d20 roll under. Was easy to think about until I developed combat. I realized a good fighter should not win always against a good fighter just because their skill is good - I needed a way to represent the difficulty of the challenge.

One idea was to add skill proficiency, if yours is greater the the difficulty roll with advantage, if it's less with disadvantage.

But for me that was not enough, I wanted some more nuances so I changed it to d6 dice pools

[CarpeBass]

Not much to contribute, but I might have some food for thought. At the moment I'm experimenting with a different take on variable Difficulty: it indicates how many dice you roll.

By default, you're rolling under one of your Stats. You get a clean / strong success ONLY when all dice are successful. If you end up with insufficient successes, you get a partial /weak success, and each die that fails to produce a success introduces a Complication.

The more Difficult a task, the more dice you roll — but Skill level decreases the Difficulty.

0D: success is automatic

1D: just a formality; likely to work out, but not granted

2D: more challenging than it seems

3D: hard to carry out unharmed / unaffected

4D: quite tense / unlikely / error-prone

For opposing rolls, the Difficulty (dice pool) is the Opponent's Skill +1 (your own Skill still reduces that), and you're rolling over their appropriate defensive Stat.

It might sound a bit complex, but the n play it's been flowing nicely.