What is D&D? A Simple Guide for Actual Play
D&D or DnD means Dungeons and Dragons, which is a tactical improv roleplaying game where you play the role of a powerful hero that goes on adventures and fights fearsome mythological monsters.
What separates D&D from a videogame RPG is the DM (Dungeon Master), an additional player that acts as a referee and arbiter for both the rules and the unexpected. In a videogame, everything is scripted and written ahead of time, so you are playing through the developer's story like you would a book or movie, and certain actions simply aren't possible due to the budget contraints of creating static media. In D&D, any action you can think of is possible, which allows for totally unpredictable outcomes and emergent storylines. In D&D everyone works together to craft a unique narrative using dice, rules, and improvisation.
How Play Works
D&D is ideally played with 3-5 players and 1 DM. The DM begins play by describing the current location (appearance, sound, smells), as well as any NPCs (non-player characters) that are present. The players then take turns describing what their PCs (player characters) do, with the DM adjudicating when necessary. If a player interacts with any NPCs, the DM will play the role of the NPC and decide on their knowledge, mannerisms, and speech from info prepared ahead of time (like the NPC Generator) or improvised on the spot like you would in an improv game.
If a player attempts to perform an action with a chance of failure (convincing an NPC to do something they don't want to, pick a lock, attack a target, etc) then the DM will tell the player to make a skill check. The skill used is based on what the DM thinks is an appropriate skill for the task at hand (such as using Sleight of Hand when pickpocketing someone). The DM will also determine a DC (difficulty class) for the check, which is the number that must be rolled in order to succeed. If the DC for a Sleight of Hand check is 15, then the player must roll a d20 (20-sided dice or icosahedron), and add their skill bonus, which is how good their character is at that particular skill. If the player rolls a 15 or higher, then they succeed at the skill check, which means the thing they were attempting to do succeeds as they described. If the player rolls below a 15 then they fail at the skill check and the DM determines what happens instead, usually some sort of punishment or complication. This is a concept I call narrative control, and is what separates D&D from playing improv games or freeform roleplaying. There's more info on skills in in the Skill Breakdown and Skill Challenges
Narrative Control
Whether you're a player or DM, it helps to think of play in terms of narrative control. In any given scene, the DM typically starts with narrative control by describing what happens, but the players will then attempt to take narrative control by using skills, making attacks, or casting spells. In a typical improv game, there are no hard rules about who has narrative control, you're supposed to "yes, and" or "no, but" whatever the other person says. While the same improv rules apply to D&D, there are dice rolls to determine whether or not something happens, which can make the scene more exciting and unpredictable. The hero might actually die in the final confrontation with the villain, or the stirring speech might fall on deaf ears and fail. No one in the game truly knows what the outcome will be, since at any moment another player might take narrative control and turn everything on its head.
Narrative control is especially important for the DM to remember, since their role as referee naturally gives them a lot of power over the story, and it's easy to take too much narrative control by setting the DCs too high, or neutering the impact of player choice. Often as DM you need to willingly give up narrative control to the players, which can sting if you've spent a lot of time preparing something specific. For more DM-tailored information about running a game without rigid plots, check out Embrace Randomness.
Combat
There are additional rules for tactical combat, but they function similarly to a skill check. Instead of a "skill check" it's called an "attack roll" and instead of being against a particular DC it instead uses the target's AC (armor class). There's more information on how combat is different in the Player's Handbook, but for the most part you can think of making attacks as similar to making skill checks. Casting a spell on someone works the same way, but the target uses a saving throw to resist the spell against a DC instead, just like a skill.
Combat can take place on a map and grid with creature tokens/models, or with theater of the mind where everything is described and imagined instead. Typically using a grid is more tactical like a videogame, while using theater of the mind is more theatrical like a scene from a movie. D&D allows you to freely adjust the slider between game and improv to find what works best for your group.
Play Example
DM: You are at The Merciful Mug, a tavern next to a grand hall at a major crossroads in the city of Bownum. The tavern is a large timber framed building, with a blue tile roof and moss-covered walls. It contains a large grandfather clock and a craps table where 4 other patrons are playing. The owner is a human woman that mostly keeps to herself behind the bar.
Fighter: I approach the owner, "greetings! We're new in town, anything new going on?"
DM: The owner is a light-skinned woman wearing brown leather gloves, jacket, and pants. She's tall and broad shouldered, with a powerful build. Her auburn hair is unkempt and raggedy, and she's missing an eye. She looks at you with her one green eye with a bit of a sneer and a thick accent, "Well there been people disappearin' in the temple district, and there's that strange boy in the slums spoutin' doomsday prophecies."
Bard: I want to play at the craps table.
DM: There's two dragonborn men, a woman gnome, and a male human all playing, and they welcome you to join. What's your passive perception?
Bard: It's 14.
DM: After playing for a while and losing about 2 gp, you start to get the feeling something is off. You spot some subtle hand movements from the two dragonborn, and you're starting to get the feeling that they're cheating.
Bard: "Hey! I saw that, you two are trying to cheat!"
DM: The dragonborn sneer at you, "best get your eyes fixed, whelp. Accusations like that can land you in trouble."
Paladin: I step forward, "now see here, if you're not going to play by the rules then you forfeit your winnings."
DM: Make a Persuasion skill check.
Paladin: [rolls a d20 which lands on 2, adds his +5 Persuasion bonus for a total of 7] Bleh, I got a 7.
DM: The two dragonborn laugh, and one makes a rude gesture. "Buzz off and mind your business, we play how we like."
Paladin: I punch him in the face.
DM: Yeah that'll catch him by surprise, so go ahead and make an attack roll.
Paladin: [rolls a d20 which lands on 11, adds his +4 attack bonus for a total of 15] I got a 15 to hit.
DM: That connects with his face, how much damage is that?
Paladin: I have the tavern brawler feat, so I roll a d4. [rolls a d4 which lands on 3, adds his +2 strength bonus for a total of 5] That's 5 bludgeoning damage, and my feat allows me to grapple him as a bonus action. [rolls a d20 which lands on 14, adds his +4 Athletics bonus for a total of 18] I got 18 on my Athletics.
DM: He gets to roll to resist the grapple, [rolls a d20 which lands on 6, adds his +2 Athletics bonus for a total of 8] but got an 8 so you've punched and grappled him. How does that play out?
Paladin: Yeah so I come up and punch him right across the jaw, sending him stumbling back over the table. With my other hand I quickly grab his arm and twist it behind his back.
DM: He yelps in surprise, while the other patrons quickly stand from the table, and the other dragonborn reaches for his weapon. Everyone roll for initiative.
Breaking It Down
That example of play could have played out very differently, depending on the actions of the group and the results of the dice rolls. In a videogame there might have been 1 or 2 pre-determined outcomes, but in D&D the potential outcomes are infinite. If you found the dice rolls and math confusing that's ok, they're a form of arbitration and nothing more. Notice how every dice roll is similar: you roll a d20, add an appropriate modifier, and the DM determines the outcome based on the total. Dealing damage uses different dice based on the power of the attack (if the paladin had used his longsword it would have been a d8 instead of a d4), but otherwise works the same. If your group is all new players just remember the rule: d20 plus an appropriate modifier based on how good your character is at that particular task, which can either be found on your character sheet or agreed to by the DM if you're unsure.
In the play example above, the DM asked for a skill check whenever a player attempted to gain narrative control. The paladin attempted to convince two cheaters to give up their winnings, which they're not going to want to do. For such a situation you could say an appropriate DC is around 10-15 (based on the tables in Skill Breakdown and Skill Challenges), and if the paladin had rolled that high then the cheaters would have done as asked, maybe a bit rudely and apprehensively as befits their personalities. When DMing it's best to keep this concept of narrative control in mind, let the players attempt things and take control of the narrative, and let the dice determine whether they succeed. Notice also that when the paladin successfully punched and grappled the dragonborn, the DM asked the paladin to describe what happened, giving the paladin permission to exert total narrative control after their success.
If you thought to yourself, "I could never come up with descriptions like that," then good news! They're directly from the Town Generator and NPC Generator. If you're interested in trying D&D but don't quite feel comfortable yet playing with others, then you may enjoy the No DM Adventures found here. There are also fully ready and self-contained No Prep Modules found in that same section if you want to try running a game for a group but don't know where to start.
Need more help with your campaign? Check out all the other tools, generators, and articles: kassoon.com/dnd/
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