Dexterity represents a character’s agility, nimbleness, and ability to avoid physical threats. Characters with high Dexterity are skilled with finesse and ranged weapons, often wear light armor or no armor in combat, and are often stealthy.
Dexterity and Skills
Acrobatics is used to perform difficult acrobatic tasks such as balancing, tumble, squeeze through narrow spaces, and maneuver while flying.
Stealth is used to hide, move silently, and otherwise avoid the notice of other creatures.
Thievery is used to disable traps and other mechanisms, pick pockets, and open locks.
Dexterity in Combat
Armor Class (AC)
Your character’s Armor Class represents your ability to avoid Strikes. An unarmored character adds their Dexterity modifier to their AC.
If you are wearing armor, your armor will have a “Dex Cap”, which is the maximum amount of Dexterity which you can add to your AC. Heavier armor has a lower dex cap, which light armor or “unarmored” armor (explorer’s clothing) will have a dex cap as high as +5.
By default, melee Strikes add your Strength modifier to both your attack and damage. However, if a weapon has the Finesse trait (dagger, rapiers, short swords, etc.), you can instead apply your Dexterity modifier to your attack rolls (though not to damage).
For example: if your character performs a Strike with a rapier, you choose to add either your Strength modifier or your Dexterity modifier, your proficiency bonus with rapiers, and any other modifiers to your d20 roll. When rolling damage, you roll the weapon’s damage dice, then add your Strength modifier and any other additional damage.
Ranged Strikes apply your Dexterity modifier to your attack, but not to damage.
Reflex saves are rolled to avoid damage from effects like fireballs, dragon’s breath, and explosions. Characters with high Reflex Save modifiers are more likely to reduce or avoid such damage.