Barons of the Stonelands
A Parry is a special manoeuvre you can perform in combat in response to a successful hit by an opponent.
After a melee attack roll to hit has bee rolled, but before damage is assigned, you may attempt to parry the blow. You may only attempt to parry an attack against a weapon up to two size categories larger than the one you wield. Natural attacks are considered to be weapons two size categories smaller than the creature’s size. You cannot parry an attack when unarmed or when denied your Dexterity bonus to AC. Attempting a parry uses up one of your attacks of opportunity for the round, and you may parry as many times per round as you have attacks of opportunity, but only against the attacks of one opponent.
To parry, you make a roll as though performing a Combat Manoeuvre (using your Combat Manoeuvre Bonus), but the target number is your opponent’s attack roll result. You may apply your shield bonus, weapon enhancement bonus, special weapon bonus (see below), and any insight, luck, or dodge bonuses to defence against that opponent that you may have. A ranger adds his favoured enemy bonus to this roll as well, if appropriate. Armour check penalties also apply. If you succeed, the attack fails and deals no damage. If you fail, the attack deal damage as normal. In either case, the opponent gets a free attempt to disarm you, which neither provokes an attack of opportunity, nor provides you with an attempt to disarm then upon failure.
Improved Parry [Combat]
You have trained at fencing, and can more easily deflect a foe’s attacks with your weapon.
Prerequisites: Combat Expertise.
Benefit: When parrying an attack, you no longer provoke a free disarm attempt. You may also parry attacks form multiple foes, so long as you have attacks of opportunity remaining. In addition, you receive a +4 bonus to your parry attempts.
These rules are adapted from the Campaign Components: Swashbucklers article that appeared in Dragon Magazine Issue 301.