Hit probabilities - # Attack dice vs Defense

[Paul Vebber]

This got buried in a couple other threads. Results greater than 99.9% become 100.0, and less than 0.1% become 0.0

Common defense values are "greyed" though evasion modifiers and die roll modifiers can make other results useful for comparison. A -1 attack DRM is effectively an increase in defense rating of 1, similarly a +1 is a reduction of one.

So a "standard" infantry unit with 6 evasion and 4 durability, defending has an 'effective' defense of 25 becasue of the -1 DRM for defending. Other DRM and mods to evasion can vary this.

NOTE: this table is based on a simulation, not closed form calculation of the odds, so as you add more dice errors of +/- 0.1% - or so may be present. The simulation rolled over 2 million dice make this chart... The fact the "50% points" for odd numbers of dice fall correctly at intevals of 7 defense (the average increase of adding 2 dice - to 0.1%) should lead to confidence in the results...

[Grotius]

Thanks for this. I also find it helpful to imagine the "average" die role as 3.5 for each dice rolled. So if I'm rolling 4 dice, on average I should expect to roll a total of 14. I can then look at the defense of the unit I'm attacking, and if it's 20, then I know it's a long shot -- in particular, that I need to average a 5 or better on each die.

[Graymane]

Ok, I know these are stupid newbie questions but what is a DRM and how do I know how much I have? Also, how do I know how what my defensive value is?

[Paul Vebber]

a Dice Roll Modifier is a DRM. The list of all the combat modieiers is on page 56 of the manual. Most are modifiers to the evasion rating that result ina DRM equal to the Durability for each +1 or -1. there are also "simple" DRMs for defending (-1 to attacker) and another -1 if defending in rought areas).

The defense value is the modified evasion rating times the durability rating.