Combat Calculator v1.0

I've been tinkering in Excel, and have come up with a prototype spreadsheet to calculate the result of any given Warhammer 40k melee combat.

Now, I don't mean the average or expected number of hits, wounds or kills, that i see a lot of people math-hammering on various forums (fora?). That stuff is pretty easy; attacks x chance to kill = average kills. But how informative is it? If your guys are going to average 3.4 kills and his are going to average 3.2, it's clear that the combat could go either way. What is the chance of actually winning the combat?

That question is what I have sought to address.


Download the file here. It is an Excel file, but no macros.

So, I present an Excel spreadsheet. Into this, you have a Squad One (under a blue heading) and Squad Two (under a yellow heading). Squad One is the squad that will get to throw its attacks first. There is also a section headed 'Strikes simultaneously?'. By writing 'TRUE' in this box, the calculator will assume that both squads hit simultaneously. No shit.

Next, fill in the probabilities for each squad to hit, wound, and beat armour (ie, for the opposing squad to fail its saves). For example, if squad one is a bunch of Incubi, and squad two is a mob of angry assault marines, I will write in for my incubi: to hit, =2/3 , to wound 0.5 (or =1/2, whatever floats your boat), failed save, 1 (because their power weapons will ignore the puny marine armour). For the assault marines (in squad 2): to hit, 0.5, to wound, =2/3, failed save, =1/3 (because the Incubi pass their 3+ save 2 times in three, they fail one time in three). Easy so far, right? The spreadsheet will proceed to calculate the odds of a 'kill'; note that this 'kill' field is the only one of these used for the actual result calculation. Thus, if you have a special case that doesn't quite fit into the hit/wound/save mould, such as Rending or Blinding Venom, you can skip to filling in appropriate 'kill' probability, and everything will be groovy.

Also fill in the numbers of, and attacks each, for each squad. You'll notice that there are two columns, number, and special weapons. The first is for all of the squaddies. The second allows you to specify a different chance to kill, for example a sergeant with a power weapon or fist in a squad of tacticals. Unfortunately at this stage of development I haven't allowed the capacity to split initative steps, so all of Squad One's attacks are resolved before Squad Two's. Bad luck if you have a power fist in Squad One :(. Maybe next version.

Then, you will see output in three different graphs, and some numbers for the curious. How is this output achieved? By calculating every possible contingency in the assault. Caveat: currently only 10 kills per squad are really supported, so it will not be entirely accurate when looking at large squads, or squads with large damage outputs. Next version I plan to upgrade to 120+, but for now think of it as a demo.

Anyway, in each of the three graphs, Squad One is blue, and Squad Two is yellow. The first graph is a small bar graph, showing the probability of scoring 0, 1, 2 ... 9, 10 kills. Next is a bar graph showing the probability of a range of combat results, from winning by 6+ to losing by the same margin, so that the math-hammering general can get a feel for the likely morale check. Finally, a pie chart shows the actual probability of winning the combat, expressed as a percentage.

Again, the colour coding should allow you to interpret the results very quickly and visually. The graphs showcase all of the relevant results; ignore all of the other number on the screen, they are really just part of the workings. I plan to move this to a less visible location next version, but that may be a while, so in the mean time I will unleash the beast!

All comments are welcome. I know that the user-interface is probably not so great at the moment, suggestions are welcome! Finally, let me know if it works for you, and helps plan your game. One day, when we are bionic, we will be able to use tools like this on the fly; when weighing up whether or not to assault, or telling your friend exactly how unlikely his gretchin trashing your reavers in hand-to-hand was (yep, true story)...