PDA

View Full Version : [nWoD Maths] Deducting dice you've already rolled.



Totally Guy
2009-11-04, 08:17 AM
I was recently rolling in combat in our Changeling game as I rolled a good number of successes to hit a guy.

"Did you deduct his defence of 2?"
"No."
"Roll it again with 2 fewer dice."

Could I propose that I roll the 2 dice now and deduct them from the success pool? Is this mathematically equivilent?

Special cases:
If I'd rolled all successes or all failure I'd have to deduct from the common pool directly.

So I roll 5 dice...
4 Successes!
"Did you deduct his defence. 2 dice?"
Then I roll 2 fails to deduct.
4 successes from 3 dice? That can't be right!

Anyone got a good fix for this? How does 10-again factor into it?

I'm just fed up of rolling epic goodness only to then be told I was meant to subtract some dice before rolling, then finding I get a radically different result.

Kesnit
2009-11-04, 08:21 AM
Reroll. Sucks, but it is the only fair way to do it, as you pointed out. And it helps you remember to deduct armor (or whatever) in the future so you don't keep losing great rolls. (Also remember, rerolling can work to your advantage.)

Edit: From my girlfriend, who ST's WoD a lot... "It is your job as a responsible player to make sure you take all the die penalties before you roll. If you don't, you will have to reroll, as that is the only fair way. You can still have 'epic goodness' after you deduct the penalties."

pasko77
2009-11-04, 08:50 AM
If the number is even, you can subtract half of the dice from the result (in the case you mention -1).
If it is odd, you can round up as a punishment! :p

Totally Guy
2009-11-04, 09:05 AM
I think there's deeper flaw in my idea beyond whether the maths works or not.

The problem is that the method would need to be consistent. If we use a deduct type manoeuver when the successes are high and we opt to reroll the lot when it's mostly failures then we get all kind of skewed up results.

No sense me forcing my ways on the rest of the group (if it even works) if it undermines my intent.

Kurald Galain
2009-11-04, 09:17 AM
I would allow such a player to simply deduct two successes. That's mathematically worse than rerolling, but if you had a good roll, it can be better.

Icebird
2009-11-04, 09:33 AM
You could also make a roll to see wich die is removed.
For example, you throw 8 dices, 3 success. But then you forgot to remove 2 dices! You then make 2 rolls of 1-8, a result of 1-5 means that a fail die is removed, a result of 6-8 mean a success die is removed.

This method would be often impratical, especially with odd number of dices/success, but in some case it can be easy to apply (half the die are success, 50% chances that each die to remove is a success one)

Fenix_of_Doom
2009-11-04, 09:58 AM
You could also make a roll to see wich die is removed.
For example, you throw 8 dices, 3 success. But then you forgot to remove 2 dices! You then make 2 rolls of 1-8, a result of 1-5 means that a fail die is removed, a result of 6-8 mean a success die is removed.

This method would be often impratical, especially with odd number of dices/success, but in some case it can be easy to apply (half the die are success, 50% chances that each die to remove is a success one)

I second this, if you have a weird number of dice, for example 7 dice, 3 success, then simply declare a reroll on 8.