Is +1OB less significant than -1D?

From what I can tell, increasing the obstacle by 1 should be more significant than reducing the dice by one, since a dice has only a (usually) 50% chance of overcoming any obstacle.

I mean… increase an OB by 1 and the dice by 1, and ultimately, the character should have a higher chance of failure. Right? Just numerically?

So, why is it that in the Anatomy of Injury, superficial wounds do +1OB for 1 or 2 wounds, then replace with removing dice as it gets worse? And greater wounds just do dice reduction?

If I understand the math correctly, you should be more impaired by a superficial wound than a light wound. Or am I missing something? Thanks!

Also, sorry I keep posting and bothering you guys :stuck_out_tongue: But I’m wanting to understand as much as I can.

-1D is closer to a penalty of +2 Ob, if I recall correctly. People that are good at math can probably explain why, but I know it’s come up several times. There are also some side-effects of losing dice, like having less opportunity to spend Fate, and becoming unable to roll skills that are reduced to 0 dice.

I don’t understand why this is true. The side effects, I 100% understand, but I don’t see how 1 dice is equal to 2 ob. Let me put forth some sample numbers to try to illustrate my question.

Let’s say you have an OB 2 challenge and a B4 skill. I’ve done the math for 4 dice - you have a 68.75% chance of success against an OB 2 challenge.

Add 1 OB and your odds of success drop to 31.25%.

Subtract 1 dice and your odds of success drop to 50%

Let me illustrate this math real fast. With 4 dice, each dice has a 50% chance of success (4-6 success, 1-3 failure). Each combination (with F for failure and S for success) has a 6.25% chance of occurring (.5^4 is the math for that). So, 4 failures is only one combination - FFFF. That’s a 6.25% chance of occurrence. 3 failures has 4 possible combinations - FFFS, FFSF, FSFF, SFFF. That’s 4*6.25, or 25% chance.

In short, the array for B4 is as follows:

6.25 4F (or 0S)
25 3F (or 1S)
37.5 2F (or 2S)
25 1F (or 3S)
6.25 0F (or 4S)

And the array for B3 is as follows:

12.5 3F (or 0S)
37.5 2F (or 1S)
37.5 1F (or 2S)
12.5 0F (or 3S)

With B4, you need at least 2 successes - you succeed on 2 successes, 3 successes, and 4 successes. So 37.5 + 25 + 6.25, or 68.75% chance of success. With 3 dice, you succeed with 2 or 3 successes, or 37.5+12.5, or 50%. Those are against OB2. Against OB 3, those odds worsen dramatically - to 31.25%.

With this array (and other arrays), it seems outright fact that 1 OB is worth approximately 2 dice, as a rule.

I simply can’t understand how it could be otherwise.

Losing dice can put you out of a fight very quickly.

I’ll expand on stormsweeper’s message: -1D means one less action, one penalty closer to having a zero in a stat and being taken out, etc. And probably some other stuff I’m forgetting.

I tried searching the forums because this comes up a lot, but alas I suck at the search I guess.

Here’s one thread I found.

Oh, and Burning Wheel Wiki on the subject.

Yeah, it was the first thread I was thinking of, and totally got it backward.

This is perfect, thank you very much. I understand how to make it work well now!

Yeah, aside from the Steel test, losing a point of Reflexes is what really makes a Light wound hurt. For most characters, this means going from 4 actions to 3 actions.

Not to mention how much it screws things up for a mage. (Every spell and spell tax at -1D ?, Break out the wheel of magic ! )

Gold also replaced “natural defenses” by and large, so your exponents are acting as your opponent’s obstacles more often. On the flip side of it, it reduces the sting of supies a bit.