Monday, June 20, 2011

Armor as DR--what it means for the game

Some quick recap.

In building off the introductory post, we see that the effectiveness of the DR depends on the armor damage (increasing the height of the red box), amount of DR (increasing the height of the black bar), monster hit rate (increasing the length of the red box and black bar), and how much defense is lost (increasing the length of the pink box).

The ultimate decision if the armor provided a net gain or net loss is, again, determined by comparing the areas of the black bar to the pink box. The black bar is the damage that would have been taken and was now absorbed by the armor. The pink box is the damage that is now taken, but would have missed but for the reduced defense.

If we calculate DR by average damage, this means that it might be more rewarding (if the monster rolls low on damage) or less rewarding (if the monster rolls high). That variability makes it an interesting tradeoff across all battles. In systems where DR is accrued without a penalty, it isn’t interesting. Gaining 2 DR is always better than zero, and 4 DR is better than 2. Without penalties, you always go for the maximum DR.

Of course, one alternative is to have armor be a penalty in other ways. You can make it expensive to acquire (in feats or in gold), have high armor checks, or reduce speed. These methods are less desirable because they make it hard for low level characters to achieve the archetype of the heavily armored character. We don’t want rule mechanics to get in the way of the game.

Making armor cost a lot to acquire is also worse because once you’ve paid the cost, you are always richly rewarded. It would be like a string of feats that each do nothing, but are prerequisites for a feat that gives +10 attack. The path to the ultimate feat is boring, and once you are there it is similarly boring, just in a different way. We want choices to provide interesting variability as often as possible. Making armor occasionally a bad call is a good (design) call.

But we cannot ignore that different tiers of armor require different investment. How do we distinguish them? Initially, Light armor is set to reduce damage taken from each hit by an average of 1% of total HP at any given level. Medium armor is 2% and Heavy armor is 3%. These percentages are maintained by allowing for magical bonuses to increase the DR granted. At the same time, different armors will have different magical properties available to them with the more powerful properties being reserved for heavier armors.

The defense lost is static and does not go away. Conceivably some feat or class could take some of it away, but I wouldn’t recommend it because then the interesting tradeoff also goes away.

Finally, I briefly mentioned the idea of cutting off armor during battle. These are the neat scenes that make the game memorable; when a knight realizes his foe hits so infrequently but so hard that he’d be better off removing his armor and just dodging. That has awesome potential, but the current rules really don’t support stuff like that. Armor currently takes long enough to don that it isn’t tenable as a “during combat” action. There is no point in writing up rules for stuff that, because of the rules you chose, will never see use. This is Type II Clutter.


  1. While I definitely feel your analysis of Armor as DR is helpful (as I'm considering using a similar system in my own game design), I feel like you're dismissing the feat approach too readily. If you allow a Feat to remove some of the drawbacks of armor, you're still creating a tradeoff but one of resource management rather than a "fluid" tradeoff.

    Now to address your concern of such a feat being boring. By itself, a feat that simply eliminates a penalty doesn't have all that much pizazz. But what if you made all forms of armor equal out of the box, up to and including the power of the magical enhancements available to them, and created feats that allow a character to specialize in a particular armor type?

    That way you could have something like this:

    Armor Training
    Description: You have trained long and hard in a particular type of armor, and wear it like a second skin.
    Benefit: Reduce the Defense penalty for one category of armor by -1, and gain a benefit based on the type of armor you selected:

    Light Armor Mobility: While wearing light armor, you may shift as a minor action 1/round.

    Medium Armor Versatility: While wearing Medium armor, you may increase the DR granted by your armor by 2 if you increase the Defense penalty by 1 or may reduce your defense penalty by 1 if you reduce your DR by 2.

    Heavy Armor Juggernaut: While wearing Heavy Armor, your Damage reduction increases by 2 until the end of your next turn if you charge, run, or otherwise move more squares than your base speed.

  2. I like the idea but I want to push back on the importance of having at least a -1 defense penalty because I think it is an important distinction.

    If the defense penalty ever goes to 0, then the character is always better off in the armor (particularly if it has magical effects). I guess this is ignoring things like skill or movement penalties, but let's set that aside for the moment and consider light armor.

    As soon as something always becomes the better choice, and particularly when we are dealing with equipment which varies from DM to DM, it starts to become boring and exploitable. It was like in 3e when Mage Armor died because Eldritch Mithril Chainshirts (or whatever they were) could be acquired for all of 2k. It stops being a decision and becomes obvious. At that point, character archetypes that don't fit become obsolete.

    Having the penalty, though, lets it be a strong strategy across levels, but still occasionally be worse. Even against a specific foe, depending on how the dice fall, it could be for boon or bane. That is neat.

    It also leads to neat moments and a variety of strategies. Imagine a scenario where a monster hits on an 18+ but a hit kills. The only tactic is to dodge. If the armor provides a penalty, then the smart move is to take it off and that will *feel* different (even if it is basically cosmetic). If armor provides no penalty, then nothing changes.

    So it isn't that shifting the tradeoff into feats is "boring" and it is also fair to say that we still made it cost something. But without an actual penalty to defense, once they paid that cost, it stops being an interesting tradeoff and becomes an obvious, ongoing build.