A quick system for assessing chances of success

[Deleted]

No chance

Horrible

Very bad

Bad -

Bad

Neutral -

Neutral

Neutral +

Good

Good +

Very good

Excellent

Guaranteed

1/100

1/12

1/6

1/4

2/6

5/12

3/6

7/12

4/6

3/4

5/6

11/12

99/100

1%

8%

17%

25%

33%

42%

50%

58%

67%

75%

83%

92%

99%

I devised this table for a friend who might DM using Swords & Sorcery soon. He's used to running 3e, and I'm afraid he'll fall back onto those mechanics when he'll need to assign odds of success on the fly. I'm sharing this system with you in case some find it useful.

Cheers!

Raphael

[ragnorakk]

That's a very helpful table!

[Ghul]

Very nice. Matthew worked out something similar for potential use in the system we are developing, but it has about half as many columns. Back before rolling 3d6 or 4d6 under your attribute became all the rage, I used to assign a reasonable percentage of success for a non-standard action, and that % was based on the circumstances, the character, and some common sense. In recent years I have returned to this method, but I will use either a d6 or a d% to determine results, or allow the player to make the roll.

[Matthew]

I did indeed (it being the table I usually have in my head when assigning percentage chances to stuff). I also like to add attributes as a percentage modifier when they are relevant, so a strength 18 character might have an 18% chance of holding up a portcullis round after round, or something like that.

[waysoftheearth]

Very nice work Leducr. I've been working to a similar guide which only includes the d6 and d12 entries.

One thing that I have found though, is that it tends to be frustrating for the players to occasionally fail at something which they expect to be really good at.

Do you guys allow a 1% chance of failure, even when success is "assured"?

I usually translate anything roughly like 5 chances in 6 of success (or better) to automatic success, and just allow the player to "talk" it thru.

I guess it is just a matter of personal taste where you set the "auto success boundary"

[Ghul]

waysoftheearth said:

Do you guys allow a 1% chance of failure, even when success is "assured"?

Nah, I don't play it like that. Too much rolling. Of course, what the player expects his character to "be very good at" and how the DM envisions how good that character actually is, can be at odds. If I feel something is within the scope of the character's concept, I might well not see the need for a roll to determine the success of a task. I'm talking about, say, a wilderness warrior creating a makeshift shelter. I don't require a roll, unless the conditions are blatantly adverse. There are some things that just do not require a roll, IMO. Such conventions, however, were born out of the proficiency system that began at the end of the 1e era, and we indeed used them, but ultimately I found them to be an unsatisfactory component of the gaming experience, but I digress. I think your 5-in-6 = success (if the player RPs it well enough) to be fine.

[Deleted]

Jun 14, 2009 17:29:32 GMT -6 waysoftheearth said:

It tends to be frustrating for the players to occasionally fail at something which they expect to be really good at.

Do you guys allow a 1% chance of failure, even when success is "assured"?

I agree with your point. Nothing frustrates me more as a player than these "critical fumble" houserules where PCs slip or skewer themselves 5% of the time in a given round.

These extremes were in italics because they're for special cases.

Some players are of a mind that the most impossible things should have a minute chance of succeeding. If so, it's only fair to assume the opposite to also be true. So, I use it more as a tool to set players straight: if they ask for too many minute-chance-of-success rolls and slow down play, then they have to deal with the flip side of the coin.

Otherwise, I rarely bring this type of roll into play. I nearly always judge extreme chances (high and low) cases as auto-success or auto-failure, especially for anything mundane or routine.

For such a roll to be justified, it has to be of significant importance, and I see the near-impossible failure (or success) as a chance to introduce an unexpected twist in the campaign. Used this way, it can generate hope/fear at critical moments when everyone has assumed the issue to be a done deal. Besides, it's nothing a Wish can't set straight!

Cheers,

Raphael