As a melee attack, a character may attempt to disarm his or her opponent. If the character does so with a weapon, he or she knocks the opponent’s weapon out of his or her hands and to the ground. If the character attempts the disarm while unarmed, the character ends up with the weapon in his or her hand.
If a character is attempting to disarm the wielder of a melee weapon, follow the steps outlined here. Disarming the wielder of a ranged weapon is slightly different; see below.
Step One: The character provokes an attack of opportunity from the target he or she is trying to disarm.
Step Two: The character and the target make opposed attack rolls with their respective weapons. If the weapons are different sizes, the combatant with the larger weapon gets a bonus on the attack roll of +4 per difference in size category. If the target is using a weapon in two hands, he or she gets an additional +4 bonus. Also, if the combatants are different sizes, the larger combatant gets a bonus on the attack roll of +4 per difference in size category.
Step Three: If the character beats the target’s attack roll, the target is disarmed. If the character attempted the disarm action unarmed, he or she now has the weapon. If the character was armed, the target’s weapon is on the ground at the target’s feet.
If the character fails the disarm attempt, the target may immediately react and attempt to disarm the character with the same sort of opposed melee attack roll. The opponent’s attempt does not provoke an attack of opportunity from the character. If the opponent fails to disarm, the character does not get a free disarm attempt against the opponent.
To disarm an opponent wielding a ranged weapon, the character makes a melee attack or unarmed attack to strike the weapon in the opponent’s hand (see Attack an Object). If the weapon is held in two hands, it gets a +2 bonus to its Defense. If the character’s attack succeeds, the ranged weapon falls to the ground or winds up in the character’s hands (if the character made the attack unarmed). This kind of disarm attempt provokes an attack of opportunity, but if the character fails, the target does not get to make a disarm attempt against him or her.