STRIKE = ROLL 1D20 + BONUSES
The act of disarming is simply getting rid of the opponent's weapon; it does no damage. The move should be declared before the 1D20 roll. It can be used as a defensive move in place of a Dodge or Parry, or can be done as a Strike attack.
The disarm move is a Strike, Hold or grappling manoeuver that causes an opponent to drop their weapon or whatever they are holding. It counts as 1 melee attack/action. Disarm does not give the weapon to the character making the disarm move. Although the item is forced out of the victim's grasp, it is either knocked away, or falls to the ground.
Typically an opponent is disarmed on a roll of a natural 19 or 20 when used as a defensive move. Roll a disarming Strike to attack as usual. High roll wins. A failed disarming attack does no damage and means one's opponent remains armed, is probably furious, and ready to strike.