Attack Roles
An attack roll determines whether an attack hits a target. An attack roll hits if the roll equals or exceeds the target’s Armor Class. Attack rolls usually occur in battle, described in “Combat” later in this chapter, but the DM might also ask for an attack roll in other situations, such as an archery competition.
Ability Modifier
The Attack Roll Abilities table shows which ability modifier to use for different types of attack rolls.
Attack Roll Abilities
| Ability | Attack Type |
|---|---|
| Strength | Melee attack with a weapon or an Unarmed Strike (see the Rules Glossary) |
| Dexterity | Ranged attack with a weapon |
| Varies | Spell attack (the ability used is determined by the spellcaster’s spellcasting feature, as explained in chapter 7) |
Some features let you use different ability modifiers from those listed. For example, the Finesse property (see “Equipment”) lets you use Strength or Dexterity with a weapon that has that property.
Proficiency
You add your Proficiency Bonus to your attack roll when you attack using a weapon you have proficiency with, as well as when you attack with a spell. See “Proficiency” later in this chapter for more information about weapon proficiencies.
Armor Class
A creature’s Armor Class represents how well the creature avoids being wounded in combat. The AC of a character is determined at character creation, whereas the AC of a monster appears in its stat block.
Calculating AC. All creatures start with the same base AC calculation:
Base AC = 10 + the creature’s Dexterity modifier
A creature’s AC can then be modified by armor, magic items, spells, and more.
Only One Base AC. Some spells and class features give characters a different way to calculate their AC. A character with multiple features that give different ways to calculate AC must choose which one to use; only one base calculation can be in effect for a creature.
Rolling 20 or 1
If you roll a 20 on the d20 (called a “natural 20”) for an attack roll, the attack hits regardless of any modifiers or the target’s AC. This is called a Critical Hit.
If you roll a 1 on the d20 (a “natural 1”) for an attack roll, the attack misses regardless of any modifiers or the target’s AC.