Behind the Screen
More Than Meets the Eye
By Jason Nelson

In the last article, we examined the implications of change in the design and management of a D&D game, including pitfalls to avoid and strategies to try while implementing changes in your campaign. The idea of changing rules, campaign settings, or any elements of your campaign and the game that you play presumes that you know what it is that you are changing. For that reason, this column will deal with perhaps the most obvious fundamental of running the game -- know the rules! This may seem like an absurdly simple point on which to base a column. I don't dispute that the point should be readily apparent to all, but in this column I will explain how a DM's knowledge of the rules (or lack thereof) impacts a game and how a DM who puts effort into mastering the rules can enhance the quality of his or her game.

If you are serving as DM, you should possess familiarity with the rules that you intend to use in the campaign, including where to find what you cannot recall off-hand. The use of tools such as a DM screen, self-made references (copying or compiling important tables or marking and tabbing pages in rulebooks), or computerized DM utilities (some of which are available on the Internet, with most for PCs but a few for Mac) can make your job much easier as well. Essentially, if you can't remember it, place the information you need at your fingertips. The ultimate goal you want to achieve is to avoid halting the flow of the game to look up references and to minimize the time and effort of finding things when you do have to stop and look. It is important to get the correct ruling, but it is also important to minimize disruption to the flow of the game. If you have mastered the rules, disruptions become minimal and allow the game to run more smoothly, which in turn better maintains the mood, tone, and immersion within the fantasy world for the players and for you.


1. Know the rules. Pay special attention to mechanics-heavy rules like combat rules, because those are the areas most likely to slow the game down.

2. Create (or purchase) some quick reference tools to access needed tables or other information quickly.

3. When making rules interpretations and judgment calls, base your rationale (as much as possible) on the rules; being able to explain the reasoning behind your judgment helps minimize arguments or complaints.

4. Be aware of the capabilities of the characters (and the skill of the players in using them) as well as the challenges you select for them. Look for the nuances of how the two interact along the lines set forth in the rules and make sure to account for variations in how you do it vs. the "standard" laid out in the rules.

5. Rules swing both ways: Anything you can do within the rules the characters can, too, and vice versa.

The term "rules lawyer" is bandied about, mostly in a derogatory way, to describe players who bend, twist, and mangle the rules to maximize advantages and minimize deficiencies (also known as "min-maxing"). In a courtroom, however, lawyers can get away only with those tactics that the judge allows, and you, as DM, must take on the role of judge in your game. To be an effective and credible judge, however, you must first demonstrate that you are a competent master of the fine points of the law -- in this case, the rules of the game. This does not mean that you must have every jot and tittle of rules minutiae on the tip of your tongue at any moment, but more than a passing familiarity is required. A DM who frequently interrupts the game to check references or who doesn't understand the rules may lose the confidence of players and is far more likely to spend time in discussions about rules interpretations.

As per the immortal "Rule 0," you, the DM, always have the final say in arguments over the game or the rules, but the use of DM fiat in place of reasoned and informed argument is high-handed and can seem capricious if invoked too frequently. Furthermore, it may frustrate and even alienate the players, who for their part have final say over whether they wish to continue playing in your campaign. You can avoid much frustration simply by having a good understanding of the rules. Knowing the rules well can increase your confidence in running the game since you should know how to competently address nearly any situation. Should a disagreement arise, a DM who knows the rules can make informed rulings and interpretations and (equally importantly) can present the rationale for the rulings that are made. Even if a player doesn't ultimately agree with your call, at least he or she can see the logical chain that led to it if you can express your rationale. Knowing the rules well also puts you in a far better position to fend off attempts by rules-savvy players who like to bend the rules to their advantage.

Quite apart from helping you become the manager of your game, a thorough knowledge of the rules is a great asset to you as an architect. When designing adventures (either homemade or adapted from published sources), knowing the rules well allows you to create appropriate challenges and rewards for the kind of game you are running. If you are not careful, you may create encounter situations that are either a death trap or a cake walk, with rewards that range from floor sweepings in a peanut factory to Monty Haul. The most recent edition of D&D has made a much more explicit effort than prior editions at defining appropriate challenges and rewards (especially in the Dungeon Master's Guide, pages 100-103, 144-145, 165-172), which not only provide quick guides to individual situations but also a level-by-level checking mechanism to see how well your campaign matches up with the presumptive archetypal adventuring party. Whether your group fits this typical mold is not important in and of itself, but it is important for you to judge in which direction it deviates if it is different, because the game makes certain assumptions in the way that it assigns CRs, ELs, and so forth.


1. Make sure everyone knows which rules are being used (including rules that have been subsequently modified by "official errata"). Have a rationale for any changes you make from the basic rule set (Player's Handbook, Dungeon Master's Guide).

2. Don't allow in a new rule just because it's in print somewhere, whether it is from an "official' D&D source or elsewhere. You should look at the rule and decide how it will impact your campaign.

3. If a rule seems outrageous, make sure you understand the rule and its effects as completely as possible before passing judgment on it.

4. Disallow rules that you find unbalance your game or make it less fun.

5. Don't create challenges that simply negate the abilities that you know the party possesses. Focus instead on using the rules to challenge them and force them to use and apply the abilities, skills, and knowledge that they have to succeed.

As an example, the game's design assumes that PCs as low as 4th or even 3rd level have the resources to acquire magic weapons, so creatures rated as being an appropriate challenge for a 3rd or 4th level party may well have damage resistance to nonmagic weapons. Obviously, if in your campaign the party is at that level and doesn't have magic weapons, then encounters will be much more difficult and warrant a higher CR or a situation-specific increase in rewards (both XP and treasure) commensurate with the increased challenge. The fact that the typical party parameters are explicitly spelled out makes it much easier to judge the degree and direction of deviation from that norm in your campaign. Knowing these rules and understanding how they work together allows you to compensate for special circumstances or more general differences in how you structure challenges and rewards in your campaign.

To extend this point a bit further, knowing the rules well allows you to understand not only the structure of the challenge/reward system and how to compare and match CRs and ELs, but also to understand the nuances of the particular abilities that both the party and their enemies bring to any meeting. This point applies to noncombat encounters as well, but a thorough knowledge of the rules is more vital in combat situations since they are generally much more game-mechanically based. You don't have to tell every secret and explain the mechanics of every creature they face. After all, much of the excitement of playing is the challenge of puzzling out how to overcome a challenge when you don't know what to expect or when you don't have full information on the situation. They may not know why an attack doesn't work against their foe or how it countered one of their own abilities, and on and on, but you should know how a creature's attack or defense or movement capabilities work and how to apply them in the game. Creatures with reach, flight, or incorporeal characteristics will fight in ways that maximize their advantages, and so it goes with any creature's abilities.

This concept applies not only to the challenges the party will face but also the party itself. After all, how can you prepare adequate challenges if you don't fully understand what the characters can do? You do not need to be an expert on every character (that is the player's job!), but you should have a good handle on what the character is capable of doing. You should not overplay such knowledge by always negating the players' advantages, but you should not be taken by surprise (or not often, at any rate) by what a character can do. You must take the general tactical capabilities of the party into account when designing challenges for them so that you can make sure that encounters are not outside the party's capabilities or that they are so easy as to be meaningless (unless there is some story-based reason for such an extreme encounter).

The basic rulebooks provide useful examples and diagrams (for example., spell areas of effect) that can clarify how things work, and some of the class-based sourcebooks (for example, Sword and Fist) do this as well. D&D also addresses rules applications in a wide range of special cases fairly consistently, with features in Dragon Magazine ("Power Play") or elsewhere on this website ("Gamestoppers"). While the game is not solely a number-crunching exercise, math is undeniably a part of the game, and by making explicit the ways that rules can be used (especially in combination), D&D greatly assists those who might not be inclined to think that way on their own. Players who want to min-max have always and will always do so, but having tools such as these built into the game system helps prevent such players from taking undue advantage of the system or less savvy (or less conniving, if you prefer) players and DMs. The above refers only to those "official" suggestions, hints, and ideas proffered by Wizards of the Coast; players and DMs can turn to innumerable other resources for advice and ideas on how to use or interpret the rules. Online newsgroups (such as Usenet's, mailing lists, and the like provide venues for asking questions and discussing (or sometimes arguing) ideas from other gamers around the world, including URLs to a host of personalized D&D-related sites. For those who don't follow such groups on a regular basis, many are archived on

The most important rule of thumb when it comes to knowing the rules is the old saying: What's good for the goose is good for the gander. When a player does come up with something creative, feel free to borrow it for your own use. If the players can do it, then so can the bad guys. Knowing the rules and knowing the capabilities of the characters (and the players) can help you anticipate their moves and choices and counter them, though you should be careful not to overplay your DM knowledge with what the villains might reasonably expect to know. Likewise, if you come up with a devious interpretation of the rules to use against the players, be certain that they will try to use it against you. Depending on your campaign, you may want to make some spells, items, prestige classes, and the like available on a limited basis (such as limiting the blackguard prestige class to only villains); as a result, they are options open to you but not open to the players. There is nothing wrong with this in principle, but you should be very careful to weigh whether the options available to each side to ensure a level playing field. For the DM, "playing fair" is not a matter of making things easy on the players, but rather making sure that everyone at the gaming table has a fair opportunity to succeed. When you know the rules and know them well, you can ensure that everyone is presented with fair challenges, reasonable rewards, and equal opportunities. That is the essence of a good game.

About the Author

Jason Nelson lives in Seattle and is a full-time homemaker (taking care of his 7-year-old daughter, 4-year-old son, and new dog), a part-time graduate student (working on a Ph.D. in education policy), and an active and committed born-again Christian. He runs a weekly D&D game, having just completed a seven-year-long AD&D (heavily modified) campaign set in the Forgotten Realms. He began playing D&D in 1981, and he also plays in a biweekly campaign with a D&D version of his very first character (Tjaden Ludendorff, a psionic paladin) from 21 years ago!

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