Friday, 24 August 2012

Black Powder Command Rolls

It's been a while since I've mentioned the Black Powder rules on this blog. I've enjoyed developing my own rules, but I still regard BP as my favourite commercial set. My reason for posting here is to pass on some info which might be useful to players. Many may already be aware of this slight inconsistency in the rules but I reckon many will not - I first read about it over a year ago on another gamer's blog and I didn't really take it on board then.

Anyway, browsing the net I rediscovered the appropriate post on Craig Welter's wargames blog, Adventures In Miniature Gaming. I think most BP players (like me) assume without thinking about it that when making a command roll, getting one move is more likely than getting 2, which in turn is more likely than getting three. This would surely be logical. But as the rules are written, getting 2 moves is actually half as likely as getting 3 moves with a normal Staff Rating of 8. This is because the only way to throw 2 less than 8 (to get 2 moves) is by making a 6 with 2 dice, which gives you 5 chances out of 36. But to throw 5 or less with 2 dice (to get 3 moves) means you have 10 chances out of 36. Similar problems arise with other SRs. Craig's post shows all the probabilities. 

I can only assume the original rule is designed for ease of remembering. I have also seen it suggested that this greater probability of 3 moves is how the authors intended things to be, but for me at least this intention doesn't really make sense.

Craig has a very reasonable solution which works well - see his post. I will be using Craig's fix in future, which is straightforward. An alternative might be to get 3 orders only if one throws exactly 3 less than the SR. If you throw less than this, roll again.

Thanks to Craig for publicising the problem and suggesting a solution.


Jim Walkley said...

Hello Keith
I have enjoyed reading your blog and am afraid that the first time I make a comment will show the world how dense I am. I have pondered the chances of scoring 5 and 6 with two dice and, whilst agreeing that there are 5 chances of scoring 6 am unable to get more than 4 combinations which make 5. Before I adopt an alternative for BP I wonder if you would mind clarifying the 10 combinations.

Jim Walkley said...

Sorry Keith. Whilst sitting quietly with a cup of tea it dawned on me - 5 or less! Doh!
Any chance of removing my comments?

Keith Flint said...

Thanks for visiting Jim - probably best to leave your comment on, as a reminder to others. It is just the kind of slip I made when thinking about this.

Of course, happy to take the comments off if you prefer.

Cheers, Keith.

Anonymous said...

It was most certainly designed this way for a reason, and I enjoy this aspect of the command rolls.

Now, perhaps getting two orders could be a bit more common and getting three a bit less, so as an alternative "fix" that does not increase the chances of actually failing the command roll (which, of course, happens if you roll low enough with this fix), is to simply count succeeding by 2 or 3 as 2 orders, and only succeeding by 4 or more gives you three orders.

But, like I said, I wouldn't do it myself, and not because I would want to change official rules. I'm usually the first guy to do so when I find there's a need to do so.

SteveHolmes11 said...

Double and triple moves seem like a great advantage to a beginner.
Players soon learn to use them with caution.

It's all too easy to launch a single units to individual destruction at the hands of a well organised enemy formation.


Keith Flint said...

Very true Stephen. The availability of extra moves can make a game dramatic and move things on quickly, but they also require the players to make tactical decisions which add a lot of interest.