One mechanic with which many gaming systems struggle is a good Armor Class/Damage Soak system. It's tough to balance something that offers some semblance of real life situations without it getting too complex to be viable. The real challenge is developing a system that encompasses the vast range of intensities that we humans utilize to murder each other. A good armor/damage mechanic should prevent a character from being capable of slowly whittling down a Main Battle Tank with a handgun and dogged determination. It should provide that a suit of armor doesn't become totally worthless the first time its damage value is depleted. It should allow body armor to reduce damage without necessarily negating 100% of it.
There are a lot of approaches to this, but I literally dreamed up a mechanic the other night. This is the second time I've had a dream about dice mechanics; if it happens again I might need to seek help.
Keep reading to see if I make any sense when I game in my sleep.
Basic scenario: Equal Damage and Armor dice
Damage and Armor are the two rolls, which are competitive, and can use any sort of dice. So, let's say a handgun has a Damage Rating of 3d6, and it is being opposed by an Armor Rating of 3d6. The results of individual dice are compared from highest to lowest, as follows:
Damage roll (3d6): 5, 3, 1
Armor roll (3d6): 6, 4, 1
Each Armor die matched or beat each Damage die, so the armor withstood the attack, completely. It was a glancing blow, hit a hard point, was absorbed by an energy field, or repelled by a psychic mind field. In any case, the Armor won.
Another round, and another shot:
Damage roll (3d6): 5, 4, 2
Armor roll (3d6): 4, 4, 3
One die of Armor was defeated, allowing Damage to pass through, and the defending character takes damage. Further, the armor is now damaged, and loses the defeated die. The next shot will be 3d6 vs 2d6.
Damage roll (3d6): 3, 2, 1
Armor roll (2d6): 5, 5
You only match up as many dice as the defender has available, so in this case, the low die of the Damage roll is discarded and the Armor holds.
Advantage to the defender
I see this system as normally having Armor Ratings higher than Damage Ratings, so a battle matched in that way would look something like this:
Damage roll (3d6): 5, 5, 3
Armor roll (5d6): 6, 6, 3, 1, 1
Match up the individual die rolls, one-to-one, and the 6-6-3 of the Armor defeats the 5-5-3 of the Damage, nullifying any potential harm. For the next shot:
Damage roll (3d6): 6, 5, 4
Armor roll (5d6): 6, 3, 3, 2, 2
Damage wins the 5-3 and 4-3 matchups, delivering damage to the defending character, and reducing the Armor Rating from 5d6 to 3d6.
One more wrinkle before you go cross-eyed with my incredibly long and boring post. Not all Damage and Armor are made equal. Some weapons are of low-power and, in addition to having relatively few dice to roll, may only roll a 4-sided dice. A powerful cannon from an armored vehicle might roll 10-sided dice for damage, and roll far more dice as well. Likewise, personal body armor might have 2d6 of protection, while the main body of a battleship would have 50d20.
A square-off between a shooter with a plasma rifle versus some poor native wearing armor made of leather and bone might look like this:
Damage roll (6d8): 8, 6, 6, 5, 2, 1
Armor roll (2d4): 4, 4
Even a perfect roll couldn't save the native, and he sees his armor destroyed and takes what will likely be enough damage to vaporize him.
In this system, think of the vast number of ways that Damage and Armor could be customized. Want a weapon with pinpoint accuracy and penetrating power? Try a 2d10 laser rifle against that basic 3d6 armor. Maybe the personal body armor offers great coverage but is lightweight, resulting in a rating of 5d4. How important would a Skill Check or Feat be if it provided a simple +1 to a single die of the attacker's Damage Rating. A character's impressive Healing Factor could be represented by the renewal of one die of Armor Rating each round.
Lots and lots of possibilities, there.
And so on
You get the idea. This is way too much number-crunching for a Saturday morning, so I'll leave it there, for now. It has a lot of kinks to be worked out, but I think the system has some promise.
That is, of course, if someone didn't already write this and I'm now plagiarizing in my sleep.