Attacks and DefenseRule

7.12.2021

To perform an attack, you roll an attack roll against an armor class, named AC.

Making an Attack

To perform an attack, roll a d20, and add your attack modifier. This is your attack roll; compare it to your target's Armor Class. If the roll is equal to or greater than the AC, the attack hits.

Roll for damage: roll the base die, and add any modifiers. Your target takes that much damage, i.e., it loses that amount of Hit Points.

 Calculating Attack and Damage

All attack modifiers and damage values are specific to a weapon. Your character sheet lists "attack" and "damage" values for your weapons.

The attack modifier is calculated by adding the relevant ability modifier to your proficiency bonus. Melee weapons by default use Strength, ranged ones use Dexterity. Special modifiers, such as class features, may also apply.

A weapon's base damage is the sum of its damage dice + the relevant ability modifier. You do not add proficiency. There are many ways to increase damage, including class features.

Find more detailed rules on melee and ranged attacks here. Find a list of weapons here.

Critical Hits. If you roll a natural 20 on your attack roll, you score a critical hit. You hit automatically no matter the target's AC, and you roll all damage dice twice.

Calculating Armor Class

Armor Class, or AC, is the number an attacker needs to roll to hit you. You can have two kinds of armor: dAC, meaning your fencing skills and ability to step outside a blow, and hAC, your rigid defense such as plate armor or shields. Note both types on your character sheet.

Your dAC consists of 8 + your Dexterity modifier + the defense value of your weapon. It changes depending on which weapons you're wielding. If you are wielding two weapons, the second weapon can at most give you a +1.

hAC, meanwhile, is given by your armor and shield. These are usually given by your class, and listed here.

Choosing ACs

Whenever you are targeted by an attack, you can choose which AC to use. Commonly, you can just rely on your better score and ignore the other.