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Combat Statistics

This section summarizes the statistics that determine success in combat, and then details how to use
Attack Roll

An attack roll represents your attempt to strike your opponent on your turn in a round. When you make an attack roll, you roll a d20 and add your attack bonus. (Other modifiers may also apply to this roll.) If your result equals or beats the target’s Armor Class, you hit and deal damage.
Automatic Misses and Hits

A natural 1 (the d20 comes up 1) on an attack roll is always a miss. A natural 20 (the d20 comes up 20) is always a hit. A natural 20 is also a threat—a possible critical hit.
Table: Size Modifiers Size Size Modifier
Colossal -8
Gargantuan -4
Huge -2
Large -1
Medium +0
Small +1
Tiny +2
Diminutive +4
Fine +8
Attack Bonus

Your attack bonus with a melee weapon is:

Base attack bonus + Strength modifier + size modifier

With a ranged weapon, your attack bonus is:

Base attack bonus + Dexterity modifier + size modifier + range penalty

Base Attack Bonus

A base attack bonus is an attack roll bonus derived from character class and level or creature type and Hit Dice (or combinations thereof). Base attack bonuses increase at different rates for different character classes and creature types. A second attack is gained when a base attack bonus reaches +6, a third with a base attack bonus of +11 or higher, and a fourth with a base attack bonus of +16 or higher. Base attack bonuses gained from different sources, such as when a character is a multiclass character, stack.
Damage

When your attack succeeds, you deal damage. The type of weapon used determines the amount of damage you deal. Effects that modify weapon damage apply to unarmed strikes and the natural physical attack forms of creatures.

Damage reduces a target’s current hit points.
Minimum Damage

If penalties reduce the damage result to less than 1, a hit still deals 1 point of damage.
Strength Bonus

When you hit with a melee or thrown weapon, including a sling, add your Strength modifier to the damage result. A Strength penalty, but not a bonus, applies on attacks made with a bow that is not a composite bow.
Off-Hand Weapon

When you deal damage with a weapon in your off hand, you add only ½ your Strength bonus.
Wielding a Weapon Two-Handed

When you deal damage with a weapon that you are wielding two-handed, you add 1½ times your Strength bonus. However, you don’t get this higher Strength bonus when using a light weapon with two hands.
Multiplying Damage

Sometimes you multiply damage by some factor, such as on a critical hit. Roll the damage (with all modifiers) multiple times and total the results. Note: When you multiply damage more than once, each multiplier works off the original, unmultiplied damage.

Exception: Extra damage dice over and above a weapon’s normal damage are never multiplied.
Ability Damage

Certain creatures and magical effects can cause temporary ability damage (a reduction to an ability score).
Armor Class

Your Armor Class (AC) represents how hard it is for opponents to land a solid, damaging blow on you. It’s the attack roll result that an opponent needs to achieve to hit you. Your AC is equal to the following:

10 + armor bonus + shield bonus + Dexterity modifier + size modifier

Note that armor limits your Dexterity bonus, so if you’re wearing armor, you might not be able to apply your whole Dexterity bonus to your AC.

Sometimes you can’t use your Dexterity bonus (if you have one). If you can’t react to a blow, you can’t use your Dexterity bonus to AC. (If you don’t have a Dexterity bonus, nothing happens.)
Other Modifiers

Many other factors modify your AC.
Enhancement Bonuses

Enhancement effects make your armor better.
Deflection Bonus

Magical deflection effects ward off attacks and improve your AC.
Natural Armor

Natural armor improves your AC.
Dodge Bonuses

Some other AC bonuses represent actively avoiding blows. These bonuses are called dodge bonuses. Any situation that denies you your Dexterity bonus also denies you dodge bonuses. (Wearing armor, however, does not limit these bonuses the way it limits a Dexterity bonus to AC.) Unlike most sorts of bonuses, dodge bonuses stack with each other.
Touch Attacks

Some attacks disregard armor, including shields and natural armor. In these cases, the attacker makes a touch attack roll (either ranged or melee). When you are the target of a touch attack, your AC doesn’t include any armor bonus, shield bonus, or natural armor bonus. All other modifiers, such as your size modifier, Dexterity modifier, and deflection bonus (if any) apply normally.
Hit Points

When your hit point total reaches 0, you’re disabled. When it reaches -1, you’re dying. When it gets to -10, you’re dead.
Speed

Your speed tells you how far you can move in a round and still do something, such as attack or cast a spell. Your speed depends mostly on your race and what armor you’re wearing.

Dwarves, gnomes, and halflings have a speed of 20 feet (4 squares), or 15 feet (3 squares) when wearing medium or heavy armor (except for dwarves, who move 20 feet in any armor).

Humans, elves, half-elves, and half-orcs have a speed of 30 feet (6 squares), or 20 feet (4 squares) in medium or heavy armor.

If you use two move actions in a round (sometimes called a "double move" action), you can move up to double your speed. If you spend the entire round to run all out, you can move up to quadruple your speed (or triple if you are in heavy armor).
Saving Throws

Generally, when you are subject to an unusual or magical attack, you get a saving throw to avoid or reduce the effect. Like an attack roll, a saving throw is a d20 roll plus a bonus based on your class, level, and an ability score. Your saving throw modifier is:

Base save bonus + ability modifier

Base Save Bonus

A saving throw modifier derived from character class and level. Base save bonuses increase at different rates for different character classes. Base save bonuses gained from different classes, such as when a character is a multiclass character, stack.
Saving Throw Types

The three different kinds of saving throws are Fortitude, Reflex, and Will:
Fortitude

These saves measure your ability to stand up to physical punishment or attacks against your vitality and health. Apply your Constitution modifier to your Fortitude saving throws.
Reflex

These saves test your ability to dodge area attacks. Apply your Dexterity modifier to your Reflex saving throws.
Will

These saves reflect your resistance to mental influence as well as many magical effects. Apply your Wisdom modifier to your Will saving throws.
Saving Throw Difficulty Class

The DC for a save is determined by the attack itself.
Automatic Failures and Successes

A natural 1 (the d20 comes up 1) on a saving throw is always a failure (and may cause damage to exposed items; see Items Surviving after a Saving Throw). A natural 20 (the d20 comes up 20) is always a success.

Using Skills

When your character uses a skill, you make a skill check to see how well he or she does. The higher the result of the skill check, the better. Based on the circumstances, your result must match or beat a particular number (a DC or the result of an opposed skill check) for the check to be successful. The harder the task, the higher the number you need to roll.

Circumstances can affect your check. A character who is free to work without distractions can make a careful attempt and avoid simple mistakes. A character who has lots of time can try over and over again, thereby assuring the best outcome. If others help, the character may succeed where otherwise he or she would fail.
Skill Checks

A skill check takes into account a character’s training (skill rank), natural talent (ability modifier), and luck (the die roll). It may also take into account his or her race’s knack for doing certain things (racial bonus) or what armor he or she is wearing (armor check penalty), or a certain feat the character possesses, among other things.

To make a skill check, roll 1d20 and add your character’s skill modifier for that skill. The skill modifier incorporates the character’s ranks in that skill and the ability modifier for that skill’s key ability, plus any other miscellaneous modifiers that may apply, including racial bonuses and armor check penalties. The higher the result, the better. Unlike with attack rolls and saving throws, a natural roll of 20 on the d20 is not an automatic success, and a natural roll of 1 is not an automatic failure.
Difficulty Class

Some checks are made against a Difficulty Class (DC). The DC is a number (set using the skill rules as a guideline) that you must score as a result on your skill check in order to succeed.
Table: Difficulty Class Examples Difficulty (DC) Example (Skill Used)
Very easy (0) Notice something large in plain sight (Spot)
Easy (5) Climb a knotted rope (Climb)
Average (10) Hear an approaching guard (Listen)
Tough (15) Rig a wagon wheel to fall off (Disable Device)
Challenging (20) Swim in stormy water (Swim)
Formidable (25) Open an average lock (Open Lock)
Heroic (30) Leap across a 30-foot chasm (Jump)
Nearly impossible (40) Track a squad of orcs across hard ground after 24 hours of rainfall (Survival)
Opposed Checks

An opposed check is a check whose success or failure is determined by comparing the check result to another character’s check result. In an opposed check, the higher result succeeds, while the lower result fails. In case of a tie, the higher skill modifier wins. If these scores are the same, roll again to break the tie.
Table: Example Opposed Checks Task Skill (Key Ability) Opposing Skill (Key Ability)

1. An Intimidate check is opposed by the target’s level check, not a skill check. See the Intimidate skill description for more information.

Con someone Bluff (Cha) Sense Motive (Wis)
Pretend to be someone else Disguise (Cha) Spot (Wis)
Create a false map Forgery (Int) Forgery (Int)
Hide from someone Hide (Dex) Spot (Wis)
Make a bully back down Intimidate (Cha) Special1
Sneak up on someone Move Silently (Dex) Listen (Wis)
Steal a coin pouch Sleight of Hand (Dex) Spot (Wis)
Tie a prisoner securely Use Rope (Dex) Escape Artist (Dex)
Trying Again

In general, you can try a skill check again if you fail, and you can keep trying indefinitely. Some skills, however, have consequences of failure that must be taken into account. A few skills are virtually useless once a check has failed on an attempt to accomplish a particular task. For most skills, when a character has succeeded once at a given task, additional successes are meaningless.
Untrained Skill Checks

Generally, if your character attempts to use a skill he or she does not possess, you make a skill check as normal. The skill modifier doesn’t have a skill rank added in because the character has no ranks in the skill. Any other applicable modifiers, such as the modifier for the skill’s key ability, are applied to the check.

Many skills can be used only by someone who is trained in them.
Favorable And Unfavorable Conditions

Some situations may make a skill easier or harder to use, resulting in a bonus or penalty to the skill modifier for a skill check or a change to the DC of the skill check.

The chance of success can be altered in four ways to take into account exceptional circumstances.

1. Give the skill user a +2 circumstance bonus to represent conditions that improve performance, such as having the perfect tool for the job, getting help from another character (see Combining Skill Attempts), or possessing unusually accurate information.
2. Give the skill user a -2 circumstance penalty to represent conditions that hamper performance, such as being forced to use improvised tools or having misleading information.
3. Reduce the DC by 2 to represent circumstances that make the task easier, such as having a friendly audience or doing work that can be subpar.
4. Increase the DC by 2 to represent circumstances that make the task harder, such as having an uncooperative audience or doing work that must be flawless.

Conditions that affect your character’s ability to perform the skill change the skill modifier. Conditions that modify how well the character has to perform the skill to succeed change the DC. A bonus to the skill modifier and a reduction in the check’s DC have the same result: They create a better chance of success. But they represent different circumstances, and sometimes that difference is important.
Time And Skill Checks

Using a skill might take a round, take no time, or take several rounds or even longer. Most skill uses are standard actions, move actions, or full-round actions. Types of actions define how long activities take to perform within the framework of a combat round (6 seconds) and how movement is treated with respect to the activity. Some skill checks are instant and represent reactions to an event, or are included as part of an action.

These skill checks are not actions. Other skill checks represent part of movement.
Checks Without Rolls

A skill check represents an attempt to accomplish some goal, usually while under some sort of time pressure or distraction. Sometimes, though, a character can use a skill under more favorable conditions and eliminate the luck factor.
Taking 10

When your character is not being threatened or distracted, you may choose to take 10. Instead of rolling 1d20 for the skill check, calculate your result as if you had rolled a 10. For many routine tasks, taking 10 makes them automatically successful. Distractions or threats (such as combat) make it impossible for a character to take 10. In most cases, taking 10 is purely a safety measure —you know (or expect) that an average roll will succeed but fear that a poor roll might fail, so you elect to settle for the average roll (a 10). Taking 10 is especially useful in situations where a particularly high roll wouldn’t help.
Taking 20

When you have plenty of time (generally 2 minutes for a skill that can normally be checked in 1 round, one full-round action, or one standard action), you are faced with no threats or distractions, and the skill being attempted carries no penalties for failure, you can take 20. In other words, eventually you will get a 20 on 1d20 if you roll enough times. Instead of rolling 1d20 for the skill check, just calculate your result as if you had rolled a 20.

Taking 20 means you are trying until you get it right, and it assumes that you fail many times before succeeding. Taking 20 takes twenty times as long as making a single check would take.

Since taking 20 assumes that the character will fail many times before succeeding, if you did attempt to take 20 on a skill that carries penalties for failure, your character would automatically incur those penalties before he or she could complete the task. Common “take 20” skills include Escape Artist, Open Lock, and Search.
Ability Checks and Caster Level Checks

The normal take 10 and take 20 rules apply for ability checks. Neither rule applies to caster level checks.
Combining Skill Attempts

When more than one character tries the same skill at the same time and for the same purpose, their efforts may overlap.
Individual Events

Often, several characters attempt some action and each succeeds or fails independently. The result of one character’s Climb check does not influence the results of other characters Climb check.
Aid Another

You can help another character achieve success on his or her skill check by making the same kind of skill check in a cooperative effort. If you roll a 10 or higher on your check, the character you are helping gets a +2 bonus to his or her check, as per the rule for favorable conditions. (You can’t take 10 on a skill check to aid another.) In many cases, a character’s help won’t be beneficial, or only a limited number of characters can help at once.

In cases where the skill restricts who can achieve certain results you can’t aid another to grant a bonus to a task that your character couldn’t achieve alone.

See also: Aid Another in Combat
Table: Skill Synergies 5 or more ranks in… Gives a +2 bonus on…
Bluff Diplomacy checks
Bluff Disguise checks to act in character
Bluff Intimidate checks
Bluff Sleight Of Hand checks
Craft related Appraise checks
Decipher Script Use Magic Device checks involving scrolls
Escape Artist Use Rope checks involving bindings
Handle Animal Ride checks
Handle Animal wild empathy checks
Jump Tumble checks
Knowledge
(arcana) Spellcraft checks
(architecture and
engineering) Search checks involving secret doors and
similar compartments
(dungeoneering) Survival checks when underground
(geography) Survival checks to keep from getting lost
or for avoiding hazards
(history) bardic knowledge checks
(local) Gather Information checks
(nature) Survival checks in aboveground natural
environments
(nobility and royalty) Diplomacy checks
(religion) checks to turn or rebuke undead
(the planes) Survival checks when on other planes
Search Survival checks when following tracks
Sense Motive Diplomacy checks
Spellcraft Use Magic Device involving scrolls
Survival Knowledge (nature) checks
Tumble Balance checks
Tumble Jump checks
Use Magic Device Spellcraft checks to decipher scrolls
Use Rope Climb checks involving climbing ropes
Use Rope Escape Artist checks involving ropes