View Full Version : Bug in Ruleset?

August 1st, 2010, 19:55
I've noticed on a number of occasions when rolling a percentage the roll will come up as

20 and 10

I'm assuming that the 10 is the 1's roll... so the result should be 20 since the 10 should be 0, but instead it turns in 30.

I'm assuming this is because 0 is 10 on the die, and the system is adding 20 +10 rather than 20 + 0 as it should.

Anyone else seeing this? Who constructed the ruleset and could have this fixed?

August 1st, 2010, 20:15
Why do you figure that "it should" add +0? Both systems are equally valid, as far as I know. Besides it not being what you're used to, do you know any reason why it's a problem? Furthermore, I vaguely recall that it's a part of the way FG2 handles d100 rolls and can't be fixed in the ruleset, but I could be mis-remembering.

Edit: I got to this post via the "New Posts" button and hence didn't notice it in the Call of Cthulu forum. Since it is, I assume that this behavior conflicts with the CoC RPG itself... making my answer pretty useless. Sorry! :D

August 1st, 2010, 20:51
Eugene, you're right it is purely based on how I'm use to roll. I hadn't actually ran the combinations to realize that it does result in the same spectrum of possible outcomes.

I've never noticed it do this when playing 3.5, which I've been playing for over a year now. It became immediately noticable when playing this game.

I suppose it is just disconcerting, and has led to confusion by others in the group and not just me.

3.5 has an ugly feature when you roll percentage the tens die it put to the right, while the 1's die is put to the left.

I've just never ever seen dice rolled this way. I would have never guessed that it was at all common.

Seems like something that a GM should be able to configure for the game, rather than be forced upon them.

August 2nd, 2010, 05:37
As the author of the CoC mechanics, this was something that I looked into at a very early stage. Unfortunately the FG engine does not allow the 'normal' convention of treating '10' as '0' on the 1s die, so we are stuck with treating '10' as '10'.

As is noted above, the range of possible outcomes is the same, as is the probability of rolling '01' or '100' (and anything in between) and the FG methodology actually makes life slightly easier because the dice add up properly.


August 2nd, 2010, 05:39
BTW, To make life a little easier the CoC ruleset at least converts the 1s die and the 10s die to a single result in the chat window.