When you need better precision than d20 on an ability check

[tchntm43]

Suppose you are trying to do some task many times. No matter how skilled at it you are, eventually you will roll a 1, which is failure no matter your bonus or the DC.

Best example I can think of: climbing a tall cliff. Typically, according to the rules you're making a strength check every 15 ft. This means that for a very tall cliff, it becomes practically impossible for even the greatest climber in the world to succeed, simply because they'll be rolling so many times that hitting a 1 becomes very likely.

How does this situation get addressed? It seems like this would require each chance of failure being lower than 1/20 but greater than 0, which is not possible with a d20 roll.

[NRSASD]

Percentile dice, ie 2d10; one for the tens column, one for the ones. That gets you a spread of 1-99, where 0-0 is either 0 or 100.

[JNAProductions]

That's not a rule. Or, rather, it's ONLY a rule for attack rolls.

A 1st level Fighter with 16 Strength and proficiency in Athletics will never fail a DC 6 Athletics check, unless penalized by an outside source (that applies a numerical penalty, rather than disadvantage).

Up that to, say, 13th level and 20 Strength, and now they're rocking +9, meaning they never fail a DC 10 check.

[Kurt Kurageous]

Yeah, this is why a good DM won't make you reroll a check over and over.

The DM determined your course of action could succeed. In the case of climbing, they might even have told you the DC (number to tie or beat) so you could judge the risk, and then rolled ONCE.

1 does not mean automatic failure in this case, as it only means a miss on and attack roll, not an ability score check (often mistakenly called a skill check).

Your DM doesn't understand how the system works. "And they can run their game any wrong way they want." (paraphrased from Angry DM)

[Unoriginal]

Suppose you are trying to do some task many times. No matter how skilled at it you are, eventually you will roll a 1, which is failure no matter your bonus or the DC.

A 1 is only an auto-failure on an attack roll, and if a task is routine for you you generally don't have to roll at all.



Best example I can think of: climbing a tall cliff. Typically, according to the rules you're making a strength check every 15 ft.

Nope, typically climbing a tall cliff does not require a check



How does this situation get addressed?

By using the 5e rules on the subject, generally.

[Man_Over_Game]

Suppose you are trying to do some task many times. No matter how skilled at it you are, eventually you will roll a 1, which is failure no matter your bonus or the DC.

Best example I can think of: climbing a tall cliff. Typically, according to the rules you're making a strength check every 15 ft. This means that for a very tall cliff, it becomes practically impossible for even the greatest climber in the world to succeed, simply because they'll be rolling so many times that hitting a 1 becomes very likely.

How does this situation get addressed? It seems like this would require each chance of failure being lower than 1/20 but greater than 0, which is not possible with a d20 roll.

To compile the previous answers, and your questions:

Rolling a 1 does not result in an automatic failure on checks. The only time it is an automatic failure is on an attack, and the same is true for automatic successes (Rolling a 20 on your Charisma Check does not mean they are instantly infatuated with you).
Climbing a tall cliff won't necessarily require a check. A check should mostly be used to overcome explicit obstacles, not necessarily attempts. Climbing a wall might have a check if it was very difficult or if you were being harassed, but a character should generally succeed when given time and safety.

If you want more dice stability, there's two solutions I'd recommend:


Rolling more dice instead of a d20. 2d10 has a lot less deviation than a 1d20. 3d6 has less deviation than 2d8. 4d4 has less deviation than 3d6. All of these combinations have roughly the same average rolls, though, their averages ranging between 10.00-11.00. When using something like Advantage, just add a single die to whatever dice set you use (so Advantage with 2d10 is now: 3d10 keep 2).




Require multiple dice rolls, to determine a degree of "success". For example, succeeding once is a single degree of success. Succeeding twice is two degrees. You continue to roll until you either reach the maximum number of degrees of success (3 or so) or until you fail. The more degrees of success, the more heroic and more apt you are of completing the objective. Minimal success might come with risks, or completing the task poorly. Multiple degrees of success might mean that you can jump off the cliff, attack without losing balance, or catch someone as they fall. I won't go into excessive detail to avoid derailing the thread, but to make skill investments worthwhile, it's better to have multiple low checks than fewer high ones, and this system is a way of doing just that.

[JNAProductions]

Another way to do it is just have a check to determine how long it takes.

Competent adventurers won't fail to climb a cliff, barring outside circumstances like a storm or being shot at. So you could just call for an Athletics check, and say that 21+ let's them climb it in a minute, 15-20 takes two minutes, 10-14 takes five, 5-9 takes ten, and 4- has them take a whole half an hour (likely resulting from some non-harmful, but still time-consuming, falls).

[Friv]

The other simple answer: If you're requiring multiple successes in order to succeed completely, you need to require multiple failures in order to fail totally, with benefits for partial success and consequences for partial failure.

[QuickLyRaiNbow]

In addition to the above, the cliff example frequently comes with language like "failure means the character does not make progress this round. Failure by five or more means the character falls." That means that you actually only have to hit a DC of 10 to not fall. If this is a concern (and it might be!), you can often use equipment to make the check with advantage, or use a group check, or have the character who is best at the task do it and lower a ladder or rope or something.

[ProsecutorGodot]

Generally, when a check would be made frequently and your character is expected to be doing it regularly it either calls for a passive check (to detect creatures attempting to surprise you) or no check at all (The DM chooses how to resolve your requests, which isn't required to result in a roll).

For climbing specifically, that's as simple as half movement unless the climb is particularly arduous. Perhaps a normally easy obstacle for the player would require a roll this time because instead of climbing in safe conditions it is pouring rain and they're being chased by a group of enemies.

Short answer, the rules offer multiple solutions to this problem and its up to you as the DM to pick which most applies to the situation. For skill checks specifically, there is (theoretically) a plateau in skill where it is possible to become skilled enough that you will never fail.

As an example, I created a Rogue focused on Perception and Investigation. I sought out items and skills that would specifically make me better at noticing hidden creatures or objects, even those magically hidden. My passive scores for those skills were over 27 by the time the character ended his career. There was no reasonable chance that I would fail to perceive something that I would be looking for regularly. So my DM didn't have me roll.