If you wield a second weapon in your off hand, you can get one extra attack per round with that weapon. You suffer a -6 penalty with your regular attack or attacks with your primary hand and a -10 penalty to the attack with your off hand when you fight this way.
You can reduce these penalties in two ways:
If your off-hand weapon is light, the penalties are reduced by 2 each. (An unarmed strike is always considered light.)
The Two-Weapon Fighting feat lessens the primary hand penalty by 2, and the off-hand penalty by 6.
The following table summarizes the interaction of all these factors.
Circumstances
Primary Hand
Off Hand
Normal penalties
-6
-10
Off-hand weapon is light
-4
-8
Two-Weapon Fighting feat
-4
-4
Off-hand weapon is light and Two-Weapon Fighting feat
-2
-2
Double Weapons: You can use a double weapon to make an extra attack with the off-hand end of the weapon as if you were fighting with two weapons. The penalties apply as if the off-hand end of the weapon were a light weapon.
Thrown Weapons: The same rules apply when you throw a weapon from each hand. Treat a dart or shuriken as a light weapon when used in this manner, and treat a bolas, javelin, net, or sling as a one-handed weapon.
