Have anyone any experience in simulating large battles army vs army? I need to come up with a good way to simulate large battles similar to Total War with different kind of units. I have looked at Lanchester's Square Law but that doesn't take into account different unit types and I don't want it deterministic. Any suggestions?
What era are you looking at? Modern day? Medieval?
Actually, you can easily modify those equations to model unit types and a random factor, simply by making the damage rate per unit a variable. There are even graphs on that Wikipedia page illustrating this:
You can make more and less powerful unit types by simply giving them higher and lower damage rates, and introduce an element of randomness by giving each side a random modifier of +/- 10% or whatever to simulate unpredictable conditions. You could even give certain types of forces additional bonuses against others (e.g. pikemen have double damage rate against cavalry) and/or larger random factors (e.g. units with powerful but inaccurate weapons might get +/- 20% instead of 10%).
Have a look at payoff matrices. Those are the tools you use in design to discuss balancing forces that are similar (come from game theory, but don't have to be, look at how they are used by sirlin to discuss dominant strategies in fighting games).
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