Last night I noted that we had settled (for the time at least) on a 1d20 roll high to hit system in our Haphazard Homebrew™ after considering a ‘roll under armor class’ system, among other things. And in the post I wrote

As someone who’s never played an RPG engine newer than 2e AD&D, this sudden plan to use what I think is more or less the D20 core mechanic comes as a bit of a shock.

What shocked me was that someone who not only considered himself a bit of an oldschooler at heart but had never even done more than glance quickly at an RPG published after 1993 or so (not counting retro-clones of old rules) would be thinking about adopting what many in these here parts generally consider sacrilege. And I don’t understand A) why it’s generally considered sacrilege or B) why I feel that way myself.

Then a commenter on the roll low post wrote

Please don’t use a ‘core mechanic’.

An aversion to core mechanics is probably why a lot of people like retrogames, clones, and games inspired by them.

Now, I can hardly fault the guy, because I agree with him to a large degree. I think there’s more to it than “an aversion of core mechanics,” but I do think that “an aversion to core mechanics” is part of it and certainly one of the widely-discussed issues.

However, even though I think he might be at least partially right and I might agree with his sentiment, I don’t quite understand it.

Why is a “core mechanic” a bad thing?

AD&D used roll high on d20 to succeed for to-hit, saving throws, and turning undead, probably three of the most common rolls success rolls, but no one whined about it. And it used 1-in-6 or 2-in-6 for many other checks.

Is it that roll a d20 and compare it to the target’s armor class on a table is good but using a d20 to roll high with a Mace (+6, 1d6) or whatever it is that 3e uses is bad? I’ve done a lot of roll-low-on-1d12 things in our games…is that wrong because it’s getting dangerously close to a d12 core mechanic?

To be honest, this sort of strikes me as similar to the ascending vs. descending AC debate…what does it really matter which one we use if either way I need to roll a goddamn 13 for my fighter to hit the orc?

If a character has a 20% chance of finding a scroll in a library and we resolve that by rolling two d10s and reading them as percentile dice, is it fine? But what if we roll 1d20 and find the scroll on 17+? Is that suddenly wrong?

If it is wrong, what if our combat system is based on rolling low on d00? Do we need to use a roll high on some other die to find scrolls so as not flirt with a core mechanic?

I’m not trying to be argumentative…I’m simply asking some pointed questions because I’m genuinely curious about the “aversion to core mechanics,” even though I have it. Probably especially because I have it. I’ve never played a game newer than 2e AD&D or MegaTraveller, excepting retro-clones of games older than either. So it’s not personal animosity toward 3e or the piles of D20 stuff. And, as I noted last night, I’m not at all sure I would have been opposed to a D20 core mechanic back in the day.

Have I picked up a bias from spending time on oldschool blogs and forums? (If so, I blame you people. The whole bloomin’ lot of ya.)

Now that I’m thinking about this, I’m finding it strange. Is it really the mechanic? Or the fact that a standardized mechanic was adopted at the same time dice rolling (using the standardized mechanic) began to be used for so many things that used to be played out and the poor mechanic is the scapegoat?

And don’t tell me that there wouldn’t be love for a d12 core mechanic.

42 Comments to “Curious about Anti-Core Bias”

  1. Big McStrongmuscle says:

    I think for most people who hate core mechanics its just about liking some variety. A game where you have different ways of doing things tends to feel fresher than one where every action is resolved the same way. That isn’t always a good thing, but leveraged well, it can be. Personally, I like the idea of giving each class central mechanics that work very differently. That way, while a new player only has to learn one “game” to play their character, it feels like an entirely fresh and new game when you roll up something new.

    I’ve also found myself liking core mechanics less and less, for another reason. Core mechanics tend to make a game system more rules-transparent, which fits in well with a new-edition esthetic. That’s all well and good if you have a DM you don’t trust, but I’ve found over the years that when the players can’t predict the outcomes of their actions quite so clearly, the game produces a fun aura of mystery and you have to engage it with game-world logic instead of game-rules logic. Lots of byzantine, fiddly subsystems are just another way to keep the rules opaque.

    • Kilgore says:

      Lots of byzantine, fiddly subsystems are just another way to keep the rules opaque.

      This is something I have two minds about. On the one hand, anything which is considered advantageous because it keeps players in the dark about how it works seems wrong. I’m not saying that players should know all the specific target numbers and all the modifiers, but a SYSTEM which is meant to keep them from knowing how it works seems a little too much like keeping the secret art of DMing within the circle of the initiated few. Some may like that, but not me.

      On the other hand, I am a huge proponent of “you don’t need to know how to play to play.” I am always telling people that if they don’t want to even look in the book, they don’t have to. Just tell me what you want to do and I’ll tell you what happens. Maybe I’ll ask you to roll some dice first.

      But that’s meant to be an easy way to play without HAVING to learn the rules…not rules designed to be opaque to those trying to figure them out.

      • Big McStrongmuscle says:

        But that’s meant to be an easy way to play without HAVING to learn the rules…not rules designed to be opaque to those trying to figure them out.

        I don’t think you don’t need to design the rules to be hard to learn. A system that is easy to learn can be very difficult to game and vice versa. That’s basically the whole premise of cryptography. In the case of core mechanics, making things “easier to learn” can end up producing things like the 3.x skill system. The execution of the actual roll is easier, yes, but shoehorning in the d20 mechanic required a ton of complicated shenanigans to determine what the modifier and DC should be. “A flat 2-in-6 to hear noise” was MUCH easier to deal with than the formula to figure out your Listen modifier, even though though it didn’t use the same mechanic as everything else.

        Honestly, I always found the maelstrom of skill modifiers in 3.5 to be a thousand times more intimidating to new players than a paragraph-long blurbs on a class skill, even if they all work differently. Sure, maybe the system is a little more fragmented, but that fragmentation often *helps you learn*. You can’t learn all of math in one gulp, you learn it iteratively – first counting, then addition, then subtraction, and so on. D&D works the same way. First you learn how to attacks, then ability checks, then spells and saving throws, and so on. For some folks, I think using different dice for different types of rolls actually helped them keep things orderly.

        And the fringe benefit is that the interfaces between smaller systems let you be more careful about what elements affect each other. For example, the d20 combat mechanic allows for characters who almost can’t miss a character with a low enough level. That makes pretty good sense in combat, but after they generalized the mechanic to cover skills as well, a 3.5 character could without too much trouble get a high enough Bluff skill to automatically convince every 1st-level NPC he met that he was a magical pink hippo from the Sunbeam Planet, just because they hadn’t killed enough goblins to be better at detecting lies. The core mechanic didn’t make sense there, and it became an exploitable way to break the game. And then they shoehorned the whole PC skill system into monsters as well, in case you ever need to know the exact Craft (blacksmithing) skill of a tentacled illusion-puma.

        Sectioning off rules makes them easier to learn, and frees you to cut away a lot of pointless, exploitable overhead, and it lets you do it in such a way that the players don’t need to think about it. They don’t need to know, so most of them won’t bother. It’s not a panacea, and like anything else, you have to do it intelligently. But overall, I’ve found its a good thing to do.

        • Kilgore says:

          “A flat 2-in-6 to hear noise” was MUCH easier to deal with than the formula to figure out your Listen modifier, even though though it didn’t use the same mechanic as everything else.

          Honestly, I always found the maelstrom of skill modifiers in 3.5 to be a thousand times more intimidating to new players than a paragraph-long blurbs on a class skill, even if they all work differently.

          I agree, but that pretty much torpedoes the Lots of byzantine, fiddly subsystems are just another way to keep the rules opaque. advantage of non-core mechanics, no?

          but after they generalized the mechanic to cover skills as well, a 3.5 character could without too much trouble get a high enough Bluff skill to automatically convince every 1st-level NPC he met that he was a magical pink hippo from the Sunbeam Planet, just because they hadn’t killed enough goblins to be better at detecting lies.

          I take it that this example is hyperbole, but wouldn’t modifiers based on the reasonableness of the bluff be factored in? If a character with a Bluff skill target number of 3+ because he’s high level tells that lie and passes it because he rolls a 4, that’s not a problem with a core mechanic, that’s a problem with using rules and reason in a game.

  2. Core mechanics tend to make a game system more rules-transparent, which fits in well with a new-edition esthetic. That’s all well and good if you have a DM you don’t trust, but I’ve found over the years that when the players can’t predict the outcomes of their actions quite so clearly, the game produces a fun aura of mystery and you have to engage it with game-world logic instead of game-rules logic. Lots of byzantine, fiddly subsystems are just another way to keep the rules opaque.
    That’s more or less my feeling too. I don’t hate a core/universal mechanic, but I don’t always find its benefits in terms of pedagogy to outweigh its drawbacks in terms of flavor. Experience has also taught me that RPGs with core mechanics tend to encourage min-maxing and “gaming the system” a fair bit more, because their rules are immediately intelligible, whereas those without them are not as easily manipulated.

    • Kilgore says:

      Experience has also taught me that RPGs with core mechanics tend to encourage min-maxing and “gaming the system” a fair bit more

      I’m not sure if I agree with this. I’ve found myself impatient with the min/max mentality since almost day one of my gaming (well, maybe not the period when I did it too) and it hasn’t been while playing core mechanic games.

      I don’t always find its benefits in terms of pedagogy to outweigh its drawbacks in terms of flavor.

      This I think I do agree with, though I can’t explain why.

  3. KenHR says:

    I honestly think it’s a reflexive negative reaction left over from the 3e days, when the “core mechanic” was a big selling point for a lot of those who converted to the new system. I remember much being made of the “sensibility” of a one-roll mechanic (though 3e still had percentile checks and the like) by 3e adopters, and them using that to show how much better the new game was than the old. Silly in retrospect, but just about every debate in this hobby is.

    You’ve played MegaTraveller? It had a core mechanic. As a matter of fact, THAT was its big selling point when it replaced classic Traveller.

    • Kilgore says:

      You’ve played MegaTraveller? It had a core mechanic. As a matter of fact, THAT was its big selling point when it replaced classic Traveller.

      Yes, and I was going to write a bit about that but my post was already a lot longer than I had intended. I don’t remember my feelings about it at the time, probably because core mechanic bias wasn’t an issue, but I do remember thinking that it was nice knowing how to resolve a lot of things that were not specified or were a bit ambiguous in the classic game. Not that we had any trouble figuring it out previously, but I seem to remember liking it all spelled out. Didn’t play much of it, though, and except for an initial foray into it when it was first released all the Traveller I’ve played since (sadly, not much) has been classic.

  4. Fersboo says:

    I still don’t know what all the griping is about. I took a break from gaming and when I came back right before 4E, I found the d20 mechanic a great way to streamline everything. Some people need to complain no matter what: the mechanic sucks, ITS ROLE PLAYING, NOT ROLL PLAYING, or your doing it wrong.

  5. Fersboo says:

    BTW, I’m not pointing fingers at anyone in particular, just generalizing. And having a civil discussion isn’t complaining in my book.

  6. I guess I’m in the minority, but I love a unified, core mechanic. It’s what draws me to C&C over the other OSR systems.

    There have been rules lawyers for every system, old school or not, and I can see one getting miffed if a DM didn’t use the right mechanic for a particular roll. Having a core mechanic at least removes that worry.

    Much of the OSR philosophy is about not letting the rules get in the way of the game. A core mechanic can help with that because everyone always knows what they are going to roll (e.g., a d20).

    • Kilgore says:

      Much of the OSR philosophy is about not letting the rules get in the way of the game.

      Ah, that’s what they say. But mention giving magic-users magic blast and they’re all over you.

  7. Kevin says:

    I’m biased. Guilty as charged. There, that’s off my chest.

    Here’s why:
    I say Core Mechanic your system away. One of the greatest benefits you gain in a single (or limited) mechanics is an eased means for people to learn your game. Considering that a playing audience is what all games want, removing impediments is probably a good tactic to garnering said audience – and multiple different “case specific” rules or methodologies is likely to just get in the way. My personal preference is for systems that are so transparent in mechanic that I don’t have to think about how an action within them is performed or modeled. If you can manage to find a means to reasonably represent that in a small number of core mechanics, then I say that’s the tract to take.

    The preceding brought to you by pure unadulterated opinion.

  8. Erin says:

    Without too much philosophy, a core mechanic just makes my life easier as a GM. I like to tinker–using rules 100% as presented never happens–so a core mechanic makes it easier for me to add new bits where I want them.

    From the Department of Less Defensible Theories: Classic D&D grew organically–a combat roll, then saving throws, then a way to turn undead, and then a way to find secret doors, etc. Each separate mechanic was grafted on as-needed. My thought (which is mine) is that designers didn’t think about how to integrate these evolving mechanics–they thought about which dice would best represent the possible outcomes of the action at hand.

    Ladies and Gentlemen of the jury: I submit that the lack of a core mechanic is nothing more than a justification for using 6 different polyhedral dice. And I take particular exception at the short shrift suffered by the d12, who has done nothing except serve as longsword damage vs. Large opponents for decades. It is bold and evil discrimination, I say!

    • Joshua Lyle says:

      By contrast, there is Classic Traveller. The skill system uses a series of not-quite-unified mechanics, but everything else is a distinct subsystem. Yet you only need six-siders.

      • Kilgore says:

        That could have been personal preference on the part of Marc Miller, or it could simply have been because other dice were difficult to get back in the day. Separate systems don’t require separate dice, and only using one type of die doesn’t mean it’s a core mechanic.

        Though, as I noted elsewhere, I think I was pretty much in favor of the MegaTraveller core mechanic at the time. I think that I probably used some of it when we returned to classic Traveller, even, for stuff that wasn’t really specified.

    • Kilgore says:

      As I noted, there would be love for a d12 core mechanic. And, in fact, most of the d12 stuff I’ve incorporated into our various games has been to use the roll-low-on-d12 in concert with the standard x-in-6 checks already in place. I like it.

  9. Joshua Lyle says:

    Well, I see it like this: in D&D4, the options of hitting someone until they stop hitting you and talking them out of hitting you and running away so they can’t hit you all feel and work pretty much the the same, because they more-or-less use the same core mechanic, so the game feels the same regardless — everything is basically the same mechanical challenge to overcome regardless of the strategy. In OSR games, talking your way out of a fight, running from a fight, and having a fight tend to feel like different experiences, because they each use different mechanics.

    Now, which approach furthers the agenda? If I were playing something like a game involving the Raksha/Fair Folk in Exalted, having a unified core-mechanic system makes sense, because the point of the game is that the Raksha are able to percieve and affect their world and one another on the narrative level, so the choice of run, fight, talk is just so much style (which, of course, is in of itself of significant mechanical import in Exalted). But if I want the feel of a dirty, greedy, low-heroic OSR game, that approach is anathema – running and talking need to feel different and need to be real options that have different consequences, which is reinforced by giving them different mechanics.

  10. I find it strange that people only base their opinions on 3.5, as if it’s the only way to do d20.

    Microlite 20, Sword & Magic, the DCC rpg, Dan’s Diminutive 20 etc do also exist, and are a damn sight more straightforward to play than games that pride themselves on being ‘byzantine’.

    • Big McStrongmuscle says:

      It’s because 3.5 was pretty much the most recent peak of D&D sales. It makes sense to couch examples in terms of the edition that the most people have played. I’d wager that more than 75% of modern gamers have at least passing familiarity with D&D, whereas those other systems…5%? Maybe? Speaking personally, Microlite is the only one of those I know much of anything about.

    • Kilgore says:

      Hmmm. Maybe I should look again at Microlite 20.

  11. Personally, I say it’s a matter of using the right tool for the job, and a d20 is not always it.

    if I have to set the difficulty for a task by the players, using a d20 and having difficulty in increments of 5% just doesn’t appeal to me. It requires me to write down a bunch of ‘target’ numbers and think of +/- bonuses and penalties to that roll. Using a d6 feels is much more intuitive for me as the probabilities are coarse-grained enough that I can have “really hard, hard, possible, easy, simple” difficulties assigned the numbers 1-6. Quick – what’s the target d20 roll to have a 30% chance of succeeding? Does it feel different from having 35% chance?

    On the other hand, for combat where players want to be able to make meaningful choice, and we need a wide range of defense/attack capability, a d20 with 5% increments gives a nice wide range to work in. Using a d6 would cap out too soon and using a d100 provides just way too much room and becomes too fiddly with lots of tiny bonus/penalies.

    Now if the player is managing their domain and has performed a slew of different actions that impact on the happiness of his subjects, then a d100 is nice to use to determine if there is a peasant revolt as it want a accumulation of small differences to influence the roll, and d20 is just too coarse-grained.

    And if I’m rolling attribute scores, I’d like most player’s scores to have a central tendancy so I use 3d6 rather than 1d20, as a linear probability would just give me random craziness. Even 3e didn’t try to do that!

    • Kilgore says:

      Well, as for d6 being better than d20 for difficulty-based tasks, why not just

      Simple 3+ (85% vs 83%)
      Easy 7+ (65% vs 66%)
      Possible 10+ (identical)
      Hard 13+ (35% vs 33%)
      Really Hard 18+ (15% vs 16%)

      Sure, the numbers aren’t quite “evenly spaced,” but after one session you’d know them. And it’s actually EASIER to add in +1 modifiers or whatever without throwing the whole thing off. So I don’t know that the d6 is really better or that a d20 is the wrong tool for the job.

      Now, it might be more fun. I think it probably is. In fact, I was contemplating a combat system based on 1d6 rolls, roll low to hit, just like standard 1-in-6 checks.

      UPDATE: I should also add that I’m currently struggling with my spell casting system and that a more-coarse die would probably work better with “+1 modifiers or whatever” than a d20.

      • I think here we’ll just have to agree to disagree. I played for years with a d20 for task resolution and hated it. Why use the numbers 3, 7, 10, 13, and 18 when 1,2,3,4,5,6 will work just as well? But I also view handing out +5%/+10% as pretty meaningless as well. If a player can really justify it, giving them a +16.7% (or +1 on a d6) is where I feel it actually makes a difference. It’s the same with magic weapons – +1 or +2 is okay, but a +3 will really make the players sit up and notice.

        • Kilgore says:

          So it sounds like pure personal preference. Which is fine.

          • Well in the end it’s all personal preference based on what you’re trying to achieve. My point is, figure out what you’re trying to achieve, then choose the right random distribution.

          • Kilgore says:

            And my point is that if it’s a mathematical/systemic reason and not personal preference, why use the numbers 1,2,3,4,5,6 when 3, 7, 10, 13, and 18 will work just as well?

            That’s all. Like the ascending vs descending AC debate, I see all sorts of arguments trying to prove one is better or worse for this or for that and all sorts of supporting arguments thrown into the mess, but all I really see is personal preference and taste.

          • KenHR says:

            It’s all become tied in with some silly notion of gamer ideology now. Target numbers and actual percentages don’t matter. If it even resembles d20 or whatever they call 4e now, it’s teh suck.

          • I didn’t say a d20 sucks. What I said was it’s not the right die for all uses, even 3e doesn’t use a d20 for all purposes. Lord Kilgore is challenging my preference to use 6 sequential numbers; you can certainly use a d20, or any other die for that matter if you’re willing to figure out what probabilities you want. I prefer a d6 because it’s broad enough – I don’t need finer that 6 grades of difficulty. But if you prefer to have 20 grades of difficulty, then use a d20. Or give the d12 some love.

          • Kilgore says:

            I want to be clear here. I actually think I DO prefer X-in-6 checks, though I suspect I feel that way because it’s the way it’s always been done. What I’m interested in finding out is why X-in-6 is demonstrably better than better-than-X-on-d20. Other than personal preference, I haven’t seen anything convincing.

            I am personally in favor of X-in-6 or X-in-12 as an extension of X-in-6. But that doesn’t prove it to be a better system.

            I guess I’ve sort of adopted a D20-core-mechanic-is-best position in in order to try to find the root of this issue without really believing that D20-core-mechanic-is-best.

            UPDATE: What I’m trying to say after a night of $1 beers at the hockey game is that I’m playing devil’s advocate in order to reach the core of the core mechanic bias issue. I suspect that many hold the core-mechanic-is-bad position because games they don’t like use the core mechanic rather than the fact that the core mechanic is bad. I don’t know if this is the case with Rob of the North, and I’ve unfairly picked on his position to try to prove my point.

            As I stated above, I like the X-in-6 system as much as any system. I considered trying to get a common denominator X-in-6 to-hit system along the lines of PanzerBlitz, for pete’s sake.

  12. Timeshadows says:

    My response to this is on your previous post.

    • Kilgore says:

      I agree with your response and I don’t think that early D&D would have have all of those wonderful fiddly subsystems if it had been built from the ground up as a game that lots of people would play in a world where people already played those sorts of games.

      If the fiddly bits were really seen as a fundamental strength, I doubt they would have spent the time designing things to replace all the Chainmail stuff, for instance.

  13. JB says:

    My main issue with a core mechanic, is the tendency to “force” the mechanic to work for every situation, often with mediocre results, and the failure to address the issue because it would be screwing with the “core mechanic.”

    That’s the design equivalent of painting yourself into a corner.

    I like the way different systems “interact” with each other to create a more…mmm…”organic” gaming experience.

    The problem with multiple mechanics is the difficulty with navigating a labyrinthine book of different systems. Fortunately, there’s a solution: shorten your rule book.

    How hard is THAT?
    ; )

    • Kilgore says:

      My main issue with a core mechanic, is the tendency to “force” the mechanic to work for every situation, often with mediocre results

      This I can buy. In fact, I’m running into this with the spell casting system I’m trying to work out right now.

    • Joshua Lyle says:

      I think there is an important difference here between having a tight “core” system and a completely “unified” system. In the former, the important thing is reducing the critical mechanics to a small enough set to make them easy to manage. In the later, a crowbar is often needed to force things to fit.

      For instance, I have a baroque, if not rococo, system of DM tools that are practically unmanagable with dice tables (which is why I’ve coded them up in java or javascript), but I try to keep the mechanics in use at the table (as opposed to in prep) down to a very small set of core mechanics for any given mode of play.

      • Kilgore says:

        I think there is an important difference here between having a tight “core” system and a completely “unified” system.

        Very good point.

  14. […] at Lord Kilgore’s blog, in a discussion of the merits of a core mechanic as opposed to multiple mechanics in a game […]

  15. TFT, the game I truly cut my teeth on, had a strong core mechanic (3d6 roll under) that was occasionally modified to use more dice (4d6 or 5d6 roll under for a more challenging task, etc.). Basic Role-Playing, the game I play most frequently anymore, has its all-but-unified d100 mechanic. I like these things. But what I don’t like is when the “action mechanic” is also somehow tweaked to be the “damage mechanic” and the “initiative mechanic” and other such things. True20 seems to be the most egregious development in this direction to me. But there may be games that have taken it even further. If there are, I know I don’t want to play them 🙂

    A central task mechanic (a la BRP or TFT), rather than a scattershot “d20 high to hit, d20 low for attribute checks, d6 for this, d100 for that, and so on,” setup is something I prefer.

    Oh, and the very first game I designed when I was a kid was a 2d12 roll high unified (in the sense I’ve discussed above) mechanic.

  16. bombshelter13 says:

    As the guy who made the original anti-core comment, I suppose I should offer my own reasons for why I feel this way.

    When it comes right down to it, it’s pretty simple: what holds true for classes, monsters, characters, magic items, spells and adventures also holds true for game rules, and that’s that variety makes things interesting.

    If every character is the same as every other character, they become boring. If characters are different and varied, they’re much more interesting. The same goes for adventures: when they’re all alike, they’re a dreary trudge. You can go on and make similar statements about monsters, spells and almost every other major noun involved in putting together an RPG.

    But for some reason, designers have gotten it into their heads that this doesn’t apply to game mechanics, and here I disagree. In older editions a supplement providing rules for a new topic meant a treasure trove of brand new rules and systems to cover the topic – something new, not like everything you’ve seen before. Something different. Something interesting – not just another pile of DCs (or whatever you like to call them) and modifiers to throw d20s at.

    When I buy a rulebook or supplement, I want to experience that thrill of discovery.

    Vive la difference – in rules, as in all other things.

  17. Cygnus says:

    I left the following reply on the previous (Roll Low to Hit) post, but I think that bombshelter13 said basically the same thing:

    I think with “core mechanics” there’s a one-size-fits-all vibe that can develop. This seems to have hit its ultimate state in 4e (which I admit I’ve never played!), in which spells, fighting maneuvers, thief skills, ranger tracking, etc., are all handled in exactly the same way. Boring, yes, but it also implies there’s really no difference between the classes.

    In other words, once you open the door with a core mechanic, then it’s hard to stop a mindset of “game balance uber alles” from rushing in! 🙂

    All IMHO of course!

  18. […] time on lots of boards and blogs, and especially after last week’s discussion of mechanics, core and otherwise, is that I think I care a lot less about the actual mechanics of a system than a lot […]