My sister is the kind of person who doesn’t like to read instruction manuals. She’s more tactile than literary; her preferred form of learning is through trial and error. In her work as an audio engineer, this impulse serves her well. She can fiddle with a project for hours, experimenting until she gets it just right. Unfortunately, this is the same impulse that leads her to replace all of the water in a recipe for lentils with tomato paste and then wonder how she wound up with a pot of inedible crunchy glue. Never mind that she could have easily used the recipe on the back of the bag; that’s not her style. She is experiential to a fault. Rules are for other people to read.

Imagine my surprise, then, when she told me that she had been running games of Dungeons and Dragons for her housemates. She quickly revealed, however, that she didn’t own any of the sourcebooks, didn’t know most of the rules, and was basically relying on her players to let her know when she was getting something wrong in-game.

I was now considerably less surprised.

In fairness to my sister, there’s nothing inherently wrong with anything that she did. Some of my own players refuse to buy the Player’s Handbook, very few people have memorized all or even most of the rules of Dungeons and Dragons, and an experienced player can be a wonderful guide for a new dungeon master. There is also a large part of being a dungeon master that you can only learn through experience; it’s hard to know what works for your players and what doesn’t until you’ve tried it on them.

It’s just a terrible way to learn the rules of the game.

The rules can be…overwhelming.

Dungeons and Dragons is a game of exceptions and “if-then” statements with a truly massive ruleset. The Player’s Handbook is 320 pages long, and even the “Basic Rules” weigh in at about 180. Though you may be able to learn certain rules in isolation through repetition, there is no way to gain a cohesive understanding of the rules solely through trial and error. That being said, you certainly do not need to know all or most of the rules to be an excellent dungeon master. Some rules and mechanics will come up constantly, and others will never be used. The key is knowing the difference between the two. What follows are the things that I think you absolutely need to know before running a game.

Rule Zero: Always Know Where Your Handbook Is

Look at your Player’s Handbook. Repeat after me:

“This is my handbook. There are many like it, but this one is mine. Without me, my handbook is useless. Without my handbook, I am useless.”

Know your handbook. Know how it is organized, know the different subsections. Keep it within arm’s reach at all times when you’re running a game. The real secret to using the handbook is not knowing every rule and spell in it by heart, but rather knowing where in the book they are all written down. Do I remember the saving throw that a target needs to make for tasha’s hideous laughter? Not off the top of my head. But I do know that the last full section of the Player’s Handbook is the spell list, and that all of the spells in the list are organized alphabetically, so I can get you an answer in ten seconds or less. What is a monk’s proficiency bonus at level 11? I don’t know, but I do know that there’s a table at the beginning of the monk class description that will tell me, and I know that the monk class description comes between the description for fighters and the one for paladins. You can save yourself a lot of time learning what the rules are if you’re familiar with where the rules are. And you can do that much more easily if you always keep a copy of the Player’s Handbook around.

That aside, there are a few rules and mechanics that you should know before starting to run a game. These will help keep you from turning to the most-revered handbook every time you or a player need to make a roll.

Awarding Experience Points

Reduced to its most basic components, Dungeons and Dragons can be described thus: players do stuff, the dungeon master rewards them with experience points (XP) for doing stuff, and eventually they gain levels. But a lot of new players and dungeon masters think that the only way to gain experience is by killing monsters. Not so. Wizards of the Coast has what they call “the three pillars of Dungeons and Dragons”: combat, social encounters, and exploration. You can and should award your players experience for excelling in any of these categories. Did they kill a monster? Give them some XP. Did they successfully navigate the prince’s masquerade ball to find the spy plotting against the kingdom? XP! Find a cool old sword at the bottom of an old crypt that required navigating a host of deadly traps? XP! In no time, you’ll be handing out XP like Harry and Lloyd hand out cash.

To make things a little easier, I recommend that new dungeon masters use “milestone leveling.” Instead of awarding XP individually, you let your players level up when they’ve reached important moments in the story. It may feel a little more ad hoc, but you’ll appreciate giving yourself one less thing to worry about. Plus, as a player, it feels good to gain a level after you’ve killed a vampire lord. That’s just facts.

Abilities and Skills

Look at this monstrosity. Look at it.

Abilities and Skills are where a lot of new dungeon masters and new players get tripped up. It’s easy to understand why.

When you look at the character sheet, there are a lot of numbers staring you down; each ability alone has two, sometimes with negative numbers. Then there’s a long list of skills, most of which you will likely never use, and each of those has their own modifier, some of which seem inordinately high.

All of that is smoke and mirrors.

Skills are a bit of a holdover from when Dungeons and Dragons involved a lot more math. In earlier editions, players could “rank up” their skills when they leveled, like players still do in Pathfinder. But in Fifth Edition, your skills are directly tied to your abilities. Each skill is associated with a particular ability, and modifier for that skill is identical to the modifier for the associated ability. Saving throws work on the same basic principle: a saving throw modifier is just your ability modifier. Any time you tell your players to make a skill or ability check (e.g. a Persuasion check to convince the bored guardsman to let the player visit their incarcerated friend), they roll a d20 and add the appropriate modifier. If that number beats the Difficulty Class (DC) of the check or saving throw, they succeed. If not, they fail.

If you want to determine an ability modifier, you look at the ability score. To avoid an eye-crossing recitation of the precise correlation between scores and modifiers here, consult the handy chart found on page 13 of the handbook. All you need to know for now is that higher ability scores make for larger ability modifiers. Learn the chart. Love it. Or at least, remember where it is.

Combat

Combat is both the best and worst part of Dungeons and Dragons. It can set up some of the game’s greatest moments of triumph and drama, and it can be an interminable exercise in tedium and repetition. Most frustrating of all is the fact that it can do both at the same time. The section on combat in the Player’s Handbook starts on page 189, and packs a number of fiddly rules into eight pages, but here’s what you need to know to keep the pace of combat up:

At the start of combat, roll for initiative. Initiative determines the order of combat. Write down everyone’s initiative (your creature[s] included), and turns proceed from the highest number to the lowest. Once everyone has gone, a new round of combat begins with the top of the initiative order. Each round is equivalent to six seconds of time in-game.

During a single round of combat, a creature can move up to their Speed and do an Action. Stabbing an orc with a spear is an Action. Turning a werewolf into a potted plant is an Action. Bursting through a door like the Juggernaut? You guessed it: Action. Certain spells and class abilities, however, allow creatures to take a Bonus Action, which is just what it sounds like. The rules will specify if something can be done as a Bonus Action, so keep an eye out for it.

This doesn’t come close to being an exhaustive list of what you can do in combat, but this will keep you from poring over the handbook every time one of your players wants to hit a goblin with an axe.

Spells

Spells are going to be what you look up in the handbook more than any other subset of the rules. There is a full list of available spells starting on page 207 of the handbook, and it takes up a whopping eighty-three pages. It’s the majority of the last third of the handbook. Thankfully, the spells are listed in alphabetical order, and each description contains all the pertinent information.

Keep an eye out for casting times. Most spells can be cast instantly, but others — such as powerful summoning or resurrection spells — take minutes, hours, or even days to cast. Learning the distinction can mean the difference between a challenging combat encounter and your Wizard player dropping a fire elemental on your bandit camp like the Hammer of Dawn.

There are two numbers to keep in mind for spells: spell attack modifier and spell save DC. The former is added to rolls when you are trying to hit a creature with a spell (e.g. launching an acid arrow at an unsuspecting kobold), and the latter is the number a creature must roll to resist certain effects of your spells. There are formulas for both of these numbers on page 205 of the handbook. I won’t recite them here, because math is boring.

Rule Zero Prime: Enjoy Yourself

Finally, don’t worry too much about anything that I just said. There’s no rule in Dungeons and Dragons so sacrosanct that it can’t be replaced with the “Rule of Cool”: if it seems fun, just do it. If you and your players are having fun and everyone is engaged, no one is going to call you out if you occasionally flub a roll or let a player succeed when, technically, they just barely failed. At the end of the day, this is a collaborative storytelling game, not a competition. You can’t win Dungeons and Dragons. The best that you can hope for is a memorable story, one that your players enjoyed having a hand in telling.

That’s why I can’t fault my sister too much for flying by the seat of her pants. She may not remember that you’re supposed to start combat with an initiative roll, but she’s become the de facto dungeon master of her apartment, and that doesn’t happen if people aren’t having fun playing her game. She has enthusiasm and imagination; those are things that cannot be taught. The rest will come in time.

I’m still not eating her cooking, though.



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