3 March 2018

Response to "Fight Semantics" at Tao of D&D

 Alexis and I were discussing why players always want to don their armour before a fight, and we got drawn into the question of the weapon's role in the defense. Alexis is of the opinion that the weapon is already accounted for in the D&D system by the fact that we do not auto-hit an unarmed combatant. This was originally in comments on this post on Tao of D&D, and then continued here, in a new post by Alexis.

Incidentally, that first post is an excerpt from Alexis' "Masterclass" on DM'ing, available to his patrons on Patreon (of which I am one). I can highly recommend it. Alexis analyzes the DMing techniques he has used in his online campaigns in detail, outlining his thought process, what he was trying to do, what worked and what didn't, and generally giving a fascinating look inside the mind of someone who has run more D&D and thought more about the game than probably anyone around.

Alexis is uniquely suited to running a class like this, having DMed for decades, being one of the most considered thinkers on the game (as demonstrated by his long-running blog and several thoughtful books), and by virtue of having two fairly long-running campaigns run on line using Blogger (and which are therefore preserved in their entirety, and available for extensive analysis and discussion).

You should go sign up! Anyway, back to our regularly scheduled programming. I promise I'm not being paid to say that, haha!

Weapons on the Defensive - not in D&D!

Alexis was making the case that the weapon's role in your defense is already accounted for in the system.

There's only one problem with that idea - dropping your weapon does not change your opponent's chance to hit you whatsoever.

Which I would say is proof-positive that the weapon's defensive role is not, in any way, included in the system. Increasing defensive prowess with level is included (as represented by increasing HP per level). The weapon's role is decidedly not.

Increasing Defensive Skill and Hit Points

As Alexis points out, D&D uses increasing hit points to model increasing defensive ability with level, but not quite in the way Alexis described (at least not in its original incarnation, which I would argue is still the metaphor used in the game today, despite its origins being lost in time).

In Chainmail, one hit was one kill. In OD&D, *on average* one hit was one kill, but they made HP and damage both 1d6 to add a little randomness. The idea was still the Chainmail conceit that one hit killed a normal person. The Chainmail "hero" took 4 hits to kill, essentially giving the hero 3 mulligans on death, and that's the same approach that OD&D took - each additional hit die *on average* is one mulligan against death. A "hit" was always supposed to be a lethal, fight-ending blow. This neatly explains why characters fight at 100% until they're dead. The waters were muddied as time went on and hit dice and weapons started being different dice, but if you clear away the murk, that is the foundation of the current system.

The Issues with Defense in D&D

In analyzing the issues with defense in D&D combat, we need to tease out and treat individually each of the three factors to defense: hard-to-hit, hard-to-hurt, and hard-to-kill. D&D rolls hard-to-hit and hard-to-hurt into one stat (AC), but also puts some of the hard-to-hit into the hit point. It ignores the role of the weapon in hard-to-hit, despite being (possibly) the most important factor. The hit point then involves some hard-to-hit and some hard-to-kill. It's all very muddled.

This muddling causes a variety of issues. For just one, a giant-thrown boulder falling on you doesn't care one whit about your defensive abilities or your armour. It just does damage, and will do damage to Lancelot or his squire equally. But because defensive abilities and life force are rolled into your hit points, and because armour and dexterity are rolled into your hard-to-hit, it's difficult or impossible to tease out how to apply damage in a scenario like that. Theoretically, it would be something like having the giant roll against "touch AC" (which I think only existed as of 3e, being your armour class not counting your armour) and then roll damage multiplied by level (to remove the effect of increasing defensive ability being rolled into the hit points).

Also, because damage doesn't scale up with level, it means that two high-level characters who are equally matched will take a long time to finish a fight, whereas two low-level characters who are equally matched will finish quickly. Which doesn't pass the smell test to me.

Healing is difficult to reconcile into this system, because ostensibly some of your hit points are meat and blood, and some of them are fatigue, and some of them are your increased defensive ability. Well, which ones does a cure spell work on? Which ones get whittled away by walking hours in the cold? It's unclear, because the HP is a mixed metaphor from the get-go.


You can actually fix all this pretty easily in D&D combat by making the following changes.


Weapons and level influence hard-to-hit (i.e. your "AC" is set by a level modifier and a per-weapon modifier). One should actually have three hard-to-hit stats - dodge, block, and parry. Dodge is used against the giant's boulder, a ballista bolt, dragon breath, etc - anything that can't be blocked or parried. Block is used against normal missile attacks and includes the shield. Parry is used against normal melee attacks, and includes the weapon's defensive bonus.


Armour influences hard-to-hurt (i.e. it reduces incoming hit point damage).


And hit points represent only hard-to-kill (i.e. just meat and blood - all hit point loss is of a constant magnitude). This integrates naturally with Alexis' hit points for mass system.


Really, the only difference mechanically from D&D combat is including damage reduction, which is easy enough and better matches our intuitive understanding of what armour does anyway. D&D needs the three categories of hard-to-hit, it just ignores the difference (to its detriment), and it's easy enough to add these to the character sheet.

I don't think any of this is better just because it's more "realistic" (although it is). It's better because it makes each stat clearly model something understandable. This makes it intuitive, easy to understand, and easy to apply to edge cases that weren't necessarily envisioned by the designer. Because the model is explicit and understandable, it's easy for the user to tinker with it, and easy for the DM to make rulings on the fly.


  1. Can we not simply make every armour in the game 1 AC worse off and allow an armed opponent to gain +1 AC from the weapon being wielded? Seems like a very quick solution and will give an extra incentive to disarm attacks (and make fumbles more dangerous, if you play that way).

    1. I'd say no, because a) that doesn't solve the muddled mechanics, and b) it's not a strong enough effect (1 pt of AC makes very little difference).

    2. Well you say that, but remember... 1 point of AC was good enough for the shield for a pretty good amount of time in D&D's history, and who doesn't like to get their hands on a Ring of Protection +1?

    3. A shield, at 1 pt of AC, is strictly inferior to a two-handed weapon (assuming 1-hand is 1d6, 2-hand is 2d6-TH). The ring is good because there's no opportunity cost.

      From a game design standpoint, a shield should be 2 pts of AC if you want it to be tradeoff against a two-handed weapon and not just a "trap" choice that is always worse.

    4. Wow, you've never played in one of my games, wherein two handed weapons were considered strictly worse because that 1 extra AC can mean the difference between being alive and being dead. No DM fudging to protect you, all the dice were rolled out in front of everyone and increasing the average damage output by 1 point per round really did not help with the death rates. Especially as you can only put it against a single opponent per turn and often you'd miss, whereas the shield helps against multiple foes. Of course your campaigns must be quite different as you've come to the opposite conclusion, I guess it shows the vast difference in people's games.

    5. Oh and 2 hand as 2d6? What ruleset were you using? Two handed weapons are normally either d8, d6+1 or d10 depending on the rulesets I've used. Not 2d6. That's some crazy rules you're using there and calling D&D.

    6. Not 2d6, 2d6-TH - 2d6 take higher. It's a very common old-school D&D rule for two-handed weapons. You can calculate the equivalence mathematically between a damage output delta and a given AC delta, and I seem to recall that 2d6-TH is worth about 2 points of AC. Yes, this is against a single foe. I don't let you use your full hard-to-hit against multiple opponents simultaneously, because that's just nuts. That's a tweak you can't make in D&D, because hard-to-hit and hard-to-hurt are bound up together, so you can't change just the hard-to-hit against supernumerary opponents.

      And I don't play D&D, actually, so I don't call it that. I play Spells and Steel (see the title of the blog, and the subheading: "Development blog for Spells and Steel, an RPG system for simulating a low-magic 14th-century Europe, as well as general D&D, OSR, and RPG thoughts").

      I thought my mini-bio was on the sidebar, but it appears not to be anymore. In any case, it says "I'm a strong believer in the OSR, the kind of gaming it represents, and the DIY/hobby-gamer mentality." What that means is I believe that tinkering with the game is an important part of the history of RPGs.

      If you're just interested in rules as-written, you're in the wrong place and barking up the wrong tree.

    7. I added your blog through Feedly so don't see your website trimmings when I read the blog posts (title graphic or sidebar). Spells and Steel sounds interesting though, just thought it was a cool name for the blog. So bear in mind that not everyone that reads your blog is doing it by hitting it up directly, some of use Rss and Atom and we just get the posts themselves. Seems weve both made a mistake... If you read my first comment you'll see I suggested an alternative house rule that could be used for weapon ac which would be a lot simpler than what you were proposing originally, so I'm obviously not against custom rulings. Anyways the blog is a good read so don't feel discouraged.

    8. Fair enough! Thanks for the follow :)

  2. There are literally thousands of fantasy RPGs out there built around the mechanics you propose. Some of them are almost as old as OD&D (e.g. Runequest).

    OD&D combat is a series of hacks built on top of Chainmail, wherein a combat encounter between two units (i.e. squads) meant a single roll to see which one defeated the other based on the class of each unit (where "class" = combination of arms, armour, training, and I believe the number of fighters in the unit). D&D combat was not rationally designed; it grew into its current form by a process of accretion and mutation on top of a miniature wargame. Yet it works for many people, and it makes for a game that people enjoy, and it has resulted in decades of materials being written and distributed that work with this particular game and its particular mechanics.

    Your proposal is the same one made by a thousand -- no, ten thousand, one hundred thousand -- fantasy heartbreakers before you. It would require every NPC and every creature and every trap in every published supplement to be reconceived and rewritten. Why not play a game built around these mechanics rather than trying to bolt it onto D&D?

    1. I'm aware of the historical context of the evolution of D&D combat. I discuss it in this article and in others on this blog.

      These are actually very small tweaks to how D&D combat works that rationalizes the entire combat system.

      Applying these changes to existing NPCs and creatures is trivial, and can be done on the fly. It takes about 5 seconds to convert an existing NPC/creature. Traps do not need to be adjusted.


      Jim, Ftr 1, HP 6, AC 5 (chain), Sword d6 dmg

      Jim, Ftr 1, HP 6, DR 3 (chain), Sword d6 dmg

      Conversion took less time than retyping the stat block.

      Rather than being snarky ("the same [as] one hundred thousand ... fantasy heartbreakers"), why not be constructive? Point to one that does exactly what I'm proposing (I have not seen one). Explain why it doesn't work, find the hidden assumptions that fail, the design optimizations that you disagree with.

  3. I'm just going to add that I agree that classic D&D's HP and AC is a total mess. Though this does look quite a bit like runequest / GURPS, that doesn't have to be bad. Nice.

  4. It is nice to see another post from you. I really enjoy your ideas, and especially the analysis you provide on real weapon usage and how to capture the differences in simple rules adjustments.

    In one of your replies you draw attention to this being a development blog for your system; will we ever be able to see a working document for this system? I have tried incorporating some rules changes in games I've run, but it would be nice to see a coherent system taking the various ideas into account.

    1. Thanks for the kind words. Eventually, yes. Posting on the blog has fallen by the wayside, but I continue to work on the system regularly, perhaps even more.

      Yes, I definitely intend to post some pdfs of what I have when it's a little more nailed down. I continue to experiment, pull things apart and put them back together. Feels like an endless process of trial and error!

  5. Do you have any notes on the base AC of ten? Starting with a fifty-fifty chance unarmed and unarmored seems a little strange to me, and you seem like exactly the right person to address it. Sorry if you have talked about that before, could be subconsciously why I thought about it.

    1. It's something I'm thinking about these days. Historically, it's inherently arbitrary, as far as I can tell.

      Intuitively, it doesn't make sense that it's basically a coin flip.

      Right now, I'm leaning towards a base defense (i.e. without a weapon) that's quite low, possibly even zero. If you try to fight with empty hands against someone who has a sword, you're going to have a bad time. You won't be able to attack them or defend yourself in any meaningful way, seems to me.

    2. Yeah I was thinking if we started at 5 base AC (or 15 using your descending AC), then the sword could give 2 AC, a good sized kite shield could give 3 AC (or a smaller shield could give 2 AC), and then armor would give it's normal AC bonus up to 6 for platemail, which would leave room for the fighter characters to gain a point or two as class bonuses without making them invincible. Obviously that causes issues with your armor system, but those were just my thoughts on the way home from the grocery store lol I'm sure you could balance the numbers much better.

  6. I've been thinking about this issue from a D&D 5e standpoint. My thoughts are more radical. Would you mind if I got your thoughts on my ideas? I'd appreciate the advice of someone far more analytically minded than myself.