There are lots of different ways to handle personal (body) armor in an RPG. Most folks probably already get that, but...well, it feels like a necessary disclaimer before I start. D&D's "armor class" concept is a popular one (at least judging by the number of system knock-offs that continue to use it), despite certain problematic aspects of the mechanic.
Conceptually, personal armor is supposed to prevent personal injury. The usual way this gets modeled in a fantasy game includes one (or some combination) of the following mechanics:
- Reducing the chance that an opponent can inflict injury at all.
- Reducing the actual injury inflicted by an opponent's successful attack.
- Providing additional "health levels" (whatever form that takes) to the person wearing it.
- Providing a "saving throw" against damage to the person wearing it.
Additional considerations include how the use of a shield or personal agility/prowess might factor into armor, the deterioration of armor from wear-n-tear, specific hit locations versus general defense, and the usefulness of armor in preventing non-combat type injuries (like falling off a cliff, or protecting its wearer from traps and hazards).
[I may be forgetting something...it's 2:30am my time...but that's about all the iterations I can think of at the moment]
All armor systems "work" (i.e. they are functional game mechanics), but folks have different preferences when it comes to picking a specific system. System preference is based (or, IMO, should be based) on a combination of two things: personal perception of armor (perhaps changing with regard to genre), and playability (how easily it works as a game mechanic).
D&D's system (a "Type 1" mechanic) has a long history of eliciting gripes and complaints from people who have a different perception of armor and how armor should function/model. However, D&D's system is eminently playable...from a mechanic standpoint, it is incredibly simple to use in play, incredibly easy to grasp (even for new players), and incredibly quick to resolve. Its playability...and familiarity...are what has led to its staying power and proliferation across other fantasy RPGs.
Heck, its playability is probably what led to it supplanting the Chainmail combat system as the default combat system for D&D; the "D20-versus-AC" system was an alternate combat system in the pages of Men & Magic, remember? But Chainmail's personal combat system was an add-on to a mass combat war game...an afterthought for occasional "small battles and castle sieges" (when, I presume, you would have narrow battlements ramparts to defend).
But let's, for a moment, consider another fantasy RPG with war-game roots that does armor in a different flavor: Warhammer Fantasy Roleplay.
|Where "dungeon crawl" = |
"pub crawl" + weapons
- Roll to attack
- (if successful) Roll to wound (Strength versus Toughness)
- (if successful) Defender rolls to save (using armor)
And there are sometimes additional effects that need to be determined; in some editions, a failed save requires a random number of wounds (damage) to be rolled, depending on the strength of the weapon. While it seems like a lot of steps, in practice it's fairly quick and easy because of the limited range of probabilities and the ease of rolling multiple D6s and removing "dead" models. Playability, again, makes it a popular system for wargaming. The translation to RPG is a bit more clunky in execution, but because combat tends to be over quickly (with a high degree of lethality), it's fairly forgivable.
The "armor as saving throw" is the part that I find most interesting, as well as its translation to the RPG. In WFB the armor save is (was? I haven't kept up on recent editions):
- 6 for light armor
- 5-6 for heavy armor
- +1 if using a shield
- +1 if unit is mounted
That means a guy using plate and shield has a 50% chance to resist (D6 roll of 4+) any wound that would otherwise by inflicted on the character...unless struck by a weapon that ignores or penalizes the armor save (some magical or especially strong attacks).
WFRP does not have an armor save; instead armor worn reduces damage inflicted to the tune of 1 point for light armor and 2 points for heavy armor. It seems like a strange choice (to interpret the save in this way) until you consider that damage in WFRP is on a 1D6 scale...which is to say that, like OD&D (or Holmes or default B/X), all weapons in WFRP do 1D6 points of damage towards a target's wound total (hit points). If you subtract 1 point from the D6 roll (as with light armor) that means you have a 1 in 6 chance of taking no damage; if you subtract 2 points, that chance of "no damage" goes up to 2 in 6...both of which matches the save percentages of light and heavy armor.
'Course it also has the benefit of reducing damage from the blows that do land which, coupled with the multiple wounds PCs carry in WFRP, gives characters a chance to show-off some of that "heroic sticking power," even if its not as much as your typical D&D character (characters in WFRP have nowhere near as many hit points as even a mid-level PC from D&D).
|Had some neat ideas.|
WFRP, like other systems that use armor as "damage reduction," has a straight skill roll based on a person's combat ability...you see similar systems like Chaosium's BRP (Stormbringer, ElfQuest, and Pendragon as three variant examples). But those systems also get caught up in granularity...the one attack equals one swing thing (followed by a defensive dodge or parry...and possibly a riposte). While that way lies madness (I'm not interested in that type of granular scale for D&D) the point is somewhat moot, as D&D does not measure combat ability as a skill in the same way as, say fire-building or rope-tying or whatever. Not even in later editions.
Do I have a problem with the D&D combat system, with the way armor is handled? I'm not sure I do. I do like the idea of making armor a bit more important, as the ability to wear heavy armor is one of the fighter's main advantages in early editions of the game. And there are problematic aspects of the AC-system (which I've written about before). Still...this is just "thinking out loud" at this point. I'm certainly not interested in sacrificing playability, just to skew a system to match my own perception of how armor should function.