This section explains how to run a game session; later on, chapters 4 and 5 detail how to combine sessions into adventures and adventures into campaigns.
Start each game session after the first with a recap of what happened in the previous session. A recap helps players get back into the story. It also provides important information to players who missed the previous session. You can provide this recap, or you can invite one or more players to deliver the recap instead. Each approach has benefits:
DM Recap. Provide the recap yourself if you have specific information you need to impart or if you want the recap to be concise and focused on what’s relevant.
Player Recap. Let the players provide the recap if you want to gauge what they think is important or learn more about what they’re getting out of the game. If the players miss any important details in their recap, you can interject a reminder.
The bulk of a typical D&D session consists of a series of encounters, similar to how a movie is a series of scenes. In each encounter, there are chances for the DM to describe creatures and places and for characters to make choices. Encounters can involve exploration (interacting with the environment, including puzzles), social interaction with creatures, or combat. The Player’s Handbook outlines the general rhythm of play in an encounter. The following sections offer more detailed information on how an encounter typically unfolds, in three steps.
As the DM, you decide how much to tell the players and when. All the information the players need to make choices comes from you. Within the rules of the game and the limits of the characters’ knowledge and senses, tell players everything they need to know.
Published adventures often include text in a box like this, which is meant to be read aloud to the players when their characters first arrive at a location or under a specific circumstance, as described in the text. It usually describes locations so the players know what’s happening and have a sense of what their characters’ options are.
Whether you’re running a published adventure or one of your own creation, your initial description of a room or situation should focus on what the characters can perceive. You don’t have to reveal every detail at once. Most players begin to lose focus after about three sentences of descriptive text. As characters search rooms, open drawers and chests, and examine things more closely, give players more details about what their characters find.
The “Narration” section in chapter 2 offers more extensive advice and examples of narration.
Once you’re done describing the situation, ask the players what their characters want to do. Note what the players say, and identify how to resolve their actions. Ask them for more information if you need it.
Sometimes the players might give you a group answer: “We go through the door.” Other times, individual players might want to do specific things—one might search a chest while another examines a bookshelf. Outside combat, the characters don’t need to take turns, but you need to give each player a chance to tell you what their character is doing so you can decide how to resolve everyone’s actions. In combat, everyone takes turns in Initiative order.
After the players describe their characters’ actions, it’s the DM’s job to resolve those actions, guided by the rules and the adventure you’ve prepared. So how do you decide? Think through these possibilities:
No Rules Required. Sometimes, resolving a situation is easy. If an adventurer wants to cross an empty room and open a door, you can just say that the door opens and describe what lies beyond (perhaps referencing your map or notes).
Obstacles to Success. A lock, a guard, or some other obstacle might hinder a character’s ability to complete a task. In those cases, you typically call for a D20 Test, usually an ability check. For example, a successful Dexterity (Sleight of Hand) check might be needed to pick the lock, while a successful Charisma (Persuasion) check and some coins might be needed to bribe the guard. The “Resolving Outcomes” section in chapter 2 gives more guidance on how to use D20 Tests and other tools to determine the results of characters’ actions.
Roleplaying. When the players interact with other creatures, roleplay those creatures based on whether they are Friendly, Indifferent, or Hostile. Improvise based on what you know about the creatures, their knowledge, and their motivations. Then bring these creatures to life as you describe what happens. (See the “Running Social Interaction” section in chapter 2 for more advice.)
One Action at a Time. The rules about actions in the Player’s Handbook limit how many things a character can do at once. Keeping those rules in mind can help you adjudicate situations.
Combat. In combat, many situations involve attack rolls or saving throws. The rules of combat can help you determine the effectiveness of a character’s actions. The “Running Combat” section in chapter 2 offers advice on combat.
Spellcasting. If a character casts a spell, you can usually let the player tell you what the spell does and how to resolve it. If questions arise, read the text of the spell yourself—how a spell is supposed to work is usually pretty clear. The general rules of spellcasting in the Player’s Handbook are also essential for resolving a spell’s effects.
Exceptions Supersede General Rules. General rules govern each part of the game, but the game also includes class features, spells, magic items, monster abilities, and other elements that can contradict a general rule. When an exception and a general rule disagree, the exception wins. For example, it’s a general rule that melee weapon attacks use the attacking character’s Strength modifier. But if a feature says that a character can make melee weapon attacks using Charisma, that exception supersedes the general rule.
When narrating results, try to give a flavorful description while clearly communicating what’s happening in the language of the game. See the “Narration in Combat” section in chapter 2 for more advice and examples.
Describing results often leads to another decision point, which returns the flow of the game to step 1.
The game has a rhythm and flow that includes periods of action and excitement interspersed with lulls. Think of how movies show time passing between scenes. When an encounter ends, you can move on to the next one. You can often gloss over hours of travel with a quick narrative summary (see the “Travel” section in chapter 2 for more advice). Similarly, if a rest period passes uneventfully, tell the players that and move on. Don’t make the players spend time discussing which character cooks what for dinner unless they enjoy such descriptions. It’s OK to gloss over mundane details and return to the action as quickly as possible.
Expect players to discuss the events of the game, spend time planning, and engage in long conversations in character. You don’t need to be involved in those discussions unless they have questions for you. Learn to recognize the times when you can take a break as the DM, and then resume the action as soon as everyone’s ready.
Taking Breaks
When you finish a lengthy combat encounter or a tension-filled scene, or if you need time to think, take a quick break. Give your brain a few moments to refocus, relax, or prepare for the next encounter. It’s OK to leave the players in suspense during a break while you figure out the consequences of their actions.
Try not to end a game session in the middle of an encounter. It’s difficult to keep track of information such as Initiative order and other round-by-round details between sessions. An exception to this guideline is when you purposely end a session with a cliffhanger, where the story pauses just as something monumental happens or some surprising turn of events occurs. A cliffhanger can keep players intrigued and excited until the next session.
If a player missed a session and you had that player’s character leave the party for a while, make sure that there’s a way to bring the character back when the player returns. Sometimes a cliffhanger can serve this purpose: the character charges in to help their beleaguered companions.
Allow a few minutes at the end of play for everyone to discuss the events of the session. Ask your players what parts of the session they liked and what they would have liked to see more. Take notes on what happened and the situation at the end of the session so you can refer back to those notes as you prepare the next session.