Six abilities provide a quick description of every creature’s physical and mental characteristics:
Strength, measuring physical power
Dexterity, measuring agility
Constitution, measuring endurance
Intelligence, measuring reasoning and memory
Wisdom, measuring perception and insight
Charisma, measuring force of personality
Ability scores define the strengths and weaknesses of your character. The three main roles of this game -- the ability check, the saving throw, and the attack roll -- all rely on these six ability scores. Your ability scores also give your character additional effects.
Sometimes a special ability or spell tells you that you have advantage or disadvantage on an ability check, a saving throw, or an attack roll. When that happens, you roll a second d20 when you make the roll. Use the higher of the two rolls if you have advantage, and use the lower roll if you have disadvantage. For example, if you have disadvantage and roll a 17 and a 5, you use the 5. If you instead have advantage and roll those numbers, you use the 17. If multiple situations affect a roll and each one grants advantage or imposes disadvantage on it, you don’t roll more than one additional d20. If two favorable situations grant advantage, for example, you still roll only one additional d20. If circumstances cause a roll to have both advantage and disadvantage, you are considered to have neither of them, and you roll one d20. This is true even if multiple circumstances impose disadvantage and only one grants advantage or vice versa. In such a situation, you have neither advantage nor disadvantage. When you have advantage or disadvantage and something in the game, such as the halfling’s Lucky trait, lets you reroll the d20, you can reroll only one of the dice. You choose which one. For example, if a halfling has advantage on an ability check and rolls a 1 and a 13, the halfling could use the Lucky trait to reroll the 1. You usually gain advantage or disadvantage through the use of special abilities, actions, or spells. The DM can also decide that circumstances influence a roll in one direction or the other and grant advantage or impose disadvantage.
An ability check tests a character's or monster's innate talent and training in an effort to overcome a challenge. The DM calls for an ability check when a character or monster attempts an action (other than an attack) that has a chance of failure. When the outcome is uncertain, the dice determine the results.
For every ability check, the DM decides which of the six abilities is relevant to the task at hand and the difficulty of the task, represented by a Difficulty Class. The more difficult a task, the higher its DC.
Sometimes the DM may roll an ability check for you privately. For example, if you roll to investigate a room, the DM may roll your check for you and keep the number a secret. They will then tell you if you find anything. This is done to prevent meta knowledge, for example, if a player rolls a low investigation check, they will know that they probably missed something. A DM may also roll a saving throw for you without your knowledge, for example if a monster uses dominate person and you succeed the check, you should have no idea that if tried to charm you, provided it has a way of subtly casting the spell.
Sometimes one character's or monster's efforts are directly opposed to another's. This can occur when both of them are trying to do the same thing and only one can succeed, such as attempting to snatch up a magic ring that has fallen on the floor.
This situation also applies when one of them is trying to prevent the other one from accomplishing a goal--for example, when a monster tries to force open a door that an adventurer is holding closed. In situations like these, the outcome is determined by a special form of ability check, called a contest.
Both participants in a contest make ability checks appropriate to their efforts. They apply all appropriate bonuses and penalties, but instead of comparing the total to a DC, they compare the totals of their two checks. The participant with the higher check total wins the contest. That character or monster either succeeds at the action or prevents the other one from succeeding.
If the contest results in a tie, the situation remains the same as it was before the contest. Thus, one contestant might win the contest by default. If two characters tie in a contest to snatch a ring off the floor, neither character grabs it. In a contest between a monster trying to open a door and an adventurer trying to keep the door closed, a tie means that the door remains shut.
Each ability covers a broad range of capabilities, including skills that a character or a monster can be proficient in. A skill represents a specific aspect of an ability score, and an individual's proficiency in a skill demonstrates a focus on that aspect. (A character's starting skill proficiencies are determined at character creation, and a monster's skill proficiencies appear in the monster's stat block.)
For example, a Dexterity check might reflect a character's attempt to pull off an acrobatic stunt, to palm an object, or to stay hidden. Each of these aspects of Dexterity has an associated skill: Acrobatics, Sleight of Hand, and Stealth, respectively. So a character who has proficiency in the Stealth skill is particularly good at Dexterity checks related to sneaking and hiding.
Normally, your proficiency in a skill applies only to a specific kind of ability check. Proficiency in Athletics, for example, usually applies to Strength checks. In some situations, though, your proficiency might reasonably apply to a different kind of check. In such cases, the DM might ask for a check using an unusual combination of ability and skill, or you might ask your DM if you can apply a proficiency to a different check. For example, if you have to swim from an offshore island to the mainland, your DM might call for a Constitution check to see if you have the stamina to make it that far. In this case, your DM might allow you to apply your proficiency in Athletics and ask for a Constitution (Athletics) check. So if you're proficient in Athletics, you apply your proficiency bonus to the Constitution check just as you would normally do for a Strength (Athletics) check. Similarly, when your half-‐‑orc barbarian uses a display of raw strength to intimidate an enemy, your DM might ask for a Strength (Intimidation) check, even though Intimidation is normally associated with Charisma.
A passive check is a special kind of ability check that doesn't involve any die rolls. Such a check can represent the average result for a task done repeatedly, such as searching for secret doors over and over again, or can be used when the DM wants to secretly determine whether the characters succeed at something without rolling dice, such as noticing a hidden monster.
Here's how to determine a character's total for a passive check:
10 + all modifiers that normally apply to the check
If the character has advantage on the check, add 5. For disadvantage, subtract 5. The game refers to a passive check total as a score.
For example, if a 1st-level character has a Wisdom of 15 and proficiency in Perception, he or she has a passive Wisdom (Perception) score of 14.
Sometimes two or more characters team up to attempt a task. The character who's leading the effort--or the one with the highest ability modifier--can make an ability check with advantage, reflecting the help provided by the other characters. In combat, this requires the Help action.
A character can only provide help if the task is one that he or she could attempt alone. For example, trying to open a lock requires proficiency with thieves' tools, so a character who lacks that proficiency can't help another character in that task.
Moreover, a character can help only when two or more individuals working together would actually be productive. Some tasks, such as threading a needle, are no easier with help.
When a number of individuals are trying to accomplish something as a group, the DM might ask for a group ability check. In such a situation, the characters who are skilled at a particular task help cover those who aren't.
To make a group ability check, everyone in the group makes the ability check. If the average roll of the group succeeds, the whole group succeeds.
Otherwise, the group fails. Group checks don't come up very often, and they're most useful when all the characters succeed or fail as a group. For example, when adventurers are navigating a swamp, the DM might call for a group Wisdom (Survival) check to see if the characters can avoid the quicksand, sinkholes, and other natural hazards of the environment. If at least half the group succeeds, the successful characters are able to guide their companions out of danger. Otherwise, the group stumbles into one of these hazards.
In addition to being used for the Athletics skill, and strength weapon attacks and damage rolls, strength models how much your character can lift, drag, push, or pull.
During combat, you may shove, grapple, and drag other creatures, as explained in Chapter 9: Combat. Depending on your strength score, you can shove, grapple, and drag creatures of varying sizes, as shown in the table below. At the DM's discretion, some gargantuan creatures might still be too large to shove, grapple, or drag even if the chart says you can.
If your size category is increased or decreased from medium (whether permanent or temporary), you either increase or decrease your Strength score tier to match. This does not actually change your Strength score, just the bonuses/penalties associated with the tier. If the change to your size was temporary, you revert back to your actual Strength score tier when it ends.
In addition to being used for the skills Acrobatics, Sleight of Hand, and Stealth, Dexterity is also used for armor class and initiative. Dexterity measures agility, reflexes, and balance.
Constitution measures health, stamina, and vital force.
Hit points are also affected by your constitution modifier. You add your constitution modifier to each hit die you roll for hit points.
If your Constitution modifier changes, your hit point maximum changes as well, as though you had the new modifier from 1st level. For example, if you raise your Constitution score when you reach 4th level and your Constitution modifier increases from +1 to +2, you adjust your hit point maximum as though the modifier had always been +2. So you add 3 hit points for your first three levels, and then roll your hit points for 4th level using your new modifier. Or if you're 7th level and some effect lowers your Constitution score so as to reduce your Constitution modifier by 1, your hit point maximum is reduced by 7.
In addition to being used for the Arcana, History, Investigation, Nature, and Religion, intelligence is used to measure mental acuity, accuracy of recall, and the ability to reason.
Your intelligence also dictates how many extra proficiencies your character has, as shown in the Intelligence Chart below. You gain the extra proficiencies that correspond to your Intelligence score, and you also gain all the previous tiers as well. For example, if you have an Intelligence score of 15, you get the extra proficiencies listed in the 15-16 Intelligence score, and you also get the extra proficiencies listed in the 11-12 Intelligence score.
In addition to being used for the skills Animal Handling, Insight, Medicine, Perception, and Survival, wisdom reflects how attuned you are to the world around you and represents your perceptiveness and intuition.
In addition to being used for the skills Speech and Performance, charisma measures your ability to interact effectively with others. It includes factors such as confidence, eloquence, and it can represent a charming or commanding personality.
A saving throw--also called a save--represents an attempt to resist a spell, a trap, a poison, a disease, or a similar threat. You don’t normally decide to make a saving throw; you are forced to make one because your character or monster is at risk of harm.
To make a saving throw, roll a d20 and add the appropriate ability modifier. For example, you use your Dexterity modifier for a Dexterity saving throw.
A saving throw can be modified by a situational bonus or penalty and can be affected by advantage and disadvantage, as determined by the DM.
Each class gives proficiency in at least two saving throws. The wizard, for example, is proficient in Intelligence saves. As with skill proficiencies, proficiency in a saving throw lets a character add his or her proficiency bonus to saving throws made using a particular ability score. Some monsters have saving throw proficiencies as well.
The Difficulty Class for a saving throw is determined by the effect that causes it. For example, the DC for a saving throw allowed by a spell is determined by the caster’s spellcasting ability and proficiency bonus.
The result of a successful or failed saving throw is also detailed in the effect that allows the save. Usually, a successful save means that a creature suffers no harm, or reduced harm, from an effect.
At the beginning of each session, every player starts with an inspiration point. You can spend your inspiration point to reroll any roll you make, including an attack roll, saving throw, damage roll, death save, or an ability check.
You may also transfer your inspiration point to another player that doesn't have one. This doesn't cost an action, and can be done at any time, regardless of if your character can see the other players character or if they are aware of the roll.
Once Inspiration has been used on a roll, inspiration cannot be used again on the same roll.
If you use inspiration on a roll that has advantage, you roll a third d20, and then you must replace one of the original two rolls with the new one. You then still take the highest number out of the two options.
If you use inspiration on a roll that has disadvantage, you roll a third d20, and then you must replace one of the original two rolls with the new one. You then still take the lowest number out of the two options.
Once you use your inspiration point, it does not come back until you either roll a 1 on the d20 for an attack roll, saving throw, ability check, death saving throw, or if an enemy scores a critical hit against you. You do not gain an inspiration point if you did not take the natural 1 on the roll.
For example, if you have advantage and roll a 17 and 1, you took the 17, not the 1, so you do not regain an inspiration point.
You also do not regain an inspiration point if something like the halfling lucky feature allows you to reroll the natural 1, since you are no longer taking that natural 1.
You also cannot use an inspiration point on a roll that caused you to gain an inspiration point. For example, if you have no inspiration points and roll a natural 1 on an attack roll, you would gain an inspiration point. You cannot then use the inspiration point you just gained to reroll that attack roll.
Lastly, you do not gain an inspiration point if you rolled a 1 on the d20 and the outcome was still a success. For example, if you are a rogue with expertise and have a +16 to your thieves tool checks and roll a natural 1, your total is still 17. Because skill checks cannot critically fail, you would still succeed on picking a lock with a DC of 15, so you would not gain an inspiration point.
You can hold no more than 1 inspiration point at a time. If you gain another inspiration point while you already have one, then you do not gain another one.