Disarm
AP Cost: 4
Disarming an opponent removes his weapon.
When making a Disarm action, the attacker and defender make opposing Strength or Agility checks, whichever is higher, adding in their BAB. If the attacker fails, the defender may immediately make an opposed check to disarm his opponent. If this fails the two disengage. Obviously one may not attempt to disarm an unarmed attacker.
Disarm attempts made with two weapons get a +2 bonus on the check, with no additional AP cost.
If the attacker is successful, the defender is disarmed and, by default, the weapon lands on the ground. The attacker may also for 2 AP make either a strength check to throw the weapon in any direction, or a dexterity check to have the weapon land in an open hand, if any. For a throw, the distance thrown is equal to 5 feet for every 5 points by which your check exceeds a DC of 10. This cannot be used to attack people with the weapon, even crudely. An Agility check of 20 or higher ends with the weapon in your open hand, if any.
Unarmed:
Unarmed characters take a -4 penalty on their opposed Strength or Agility check unless they have Grabbed the defender previously. Additionally, unarmed characters must make an unarmed Touch Attack to initiate a disarm, Presenting an Opening (unless they have already Grabbed the opponent).
A successful unarmed disarm ends with the opponent's weapon in your hand - you may of course drop it as a free action.