System Reference Document 5.2.1
5
ExcEptions supErsEdE GEnEral rulEs
General rules govern each part of the game. For 
example, the combat rules tell you that melee at -
tacks use Strength and ranged attacks use Dexterity. 
That’s a general rule, and a general rule is in effect as 
long as something in the game doesn’t explicitly say 
otherwise.
 The game also includes elements—class features, 
feats, weapon properties, spells, magic items, mon -
ster abilities, and the like—that sometimes contra -
dict a general rule. When an exception and a general 
rule disagree, the exception wins. For example, if a 
feature says you can make melee attacks using your 
Charisma, you can do so, even though that statement 
disagrees with the general rule.
round down
Whenever you divide or multiply a number in the 
game, round down if you end up with a fraction, even 
if the fraction is one-half or greater. Some rules make 
an exception and tell you to round up.
Playing the Game
Rhythm of Play
The three main pillars of D&D play are social in -
teraction, exploration, and combat. Whichever one 
you’re experiencing, the game unfolds according to 
this basic pattern:
1: The Game Master Describes a Scene. The GM 
tells the players where their adventurers are and 
what’s around them (how many doors lead out of 
a room, what’s on a table, and so on).
2: The Players Describe What Their Characters 
Do. Typically, the characters stick together as 
they travel through a dungeon or another envi -
ronment. Sometimes different adventurers do 
different things: one adventurer might search a 
treasure chest while a second examines a mys -
terious symbol engraved on a wall and a third 
keeps watch for monsters. Outside combat, the 
GM ensures that every character has a chance to 
act and decides how to resolve their activity. In 
combat, the characters take turns.
3: The GM Narrates the Results of the Adventur -
ers’ Actions. Sometimes resolving a task is easy. 
If an adventurer walks across a room and tries to 
open a door, the GM might say the door opens and 
describe what lies beyond. But the door might be 
locked, the floor might hide a trap, or some other 
circumstance might make it challenging for an 
adventurer to complete a task. In those cases, the 
GM might ask the player to roll a die to help de -
termine what happens. Describing the results of -
ten leads to another decision point, which brings 
the game back to step 1.
This pattern holds during every game session 
(each time you sit down to play D&D), whether the 
adventurers are talking to a noble, exploring a ruin, 
or fighting a dragon. In certain situations—partic -
ularly combat—the action is more structured, and 
everyone takes turns.
The Six Abilities
All creatures—characters and monsters—have six 
abilities that measure physical and mental charac -
teristics, as shown on the Ability Descriptions table.
Ability Descriptions
Ability Score Measures …
Strength Physical might
Dexterity Agility, reflexes, and balance
Constitution Health and stamina
Intelligence Reasoning and memory
Wisdom Perceptiveness and mental fortitude
Charisma Confidence, poise, and charm
Ability Scores
Each ability has a score from 1 to 20, although some 
monsters have a score as high as 30. The score 
represents the magnitude of an ability. The Ability 
Scores table summarizes what the scores mean.
Ability Scores
Score Meaning
1 This is the lowest a score can normally go. 
If an effect reduces a score to 0, that effect 
explains what happens.
2–9 This represents a weak capability.
10 –11 This represents the human average.
12–19 This represents a strong capability.
20 This is the highest an adventurer’s score can 
go unless a feature says otherwise. 
21–29 This represents an extraordinary capability.
30 This is the highest a score can go.
Ability Modifiers
Each ability has a modifier that you apply whenever 
you make a D20 Test with that ability (explained in 
“D20 Tests”). An ability modifier is derived from its 
score, as shown in the Ability Modifiers table.