Magic Weapon Basics
Weapon Bonus
All magic weapons have a Weapon Bonus that ranges from +1 to +10. This can take the form of an enhancement bonus on attack and damage rolls when used in combat or the form of special abilities added to the weapon.
A magic weapon’s price to buy (and cost to create) is based on its total weapon bonus. In general, the market price of a weapon is equal to its weapon bonus squared × 2,000 gp + the value of the base weapon.
Spells and effects that temporarily add an enhancement bonus or special ability (such as magic weapon) do not affect a weapon’s total weapon bonus.
Enhancement Bonus
This bonus applies directly to any attack and damage roll made with the weapon when used in the normal way. Each point of enhancement bonus counts as one point of its total weapon bonus. A magic weapon may not have an enhancement bonus higher than +5.
Weapons with a +1 enhancement bonus or higher overcome DR/magic.
Hardness and Hit Points
Each +1 of enhancement bonus adds 2 to a weapon’s or shield’s hardness and +10 to its hit points.
Ranged Weapons and Ammunition
The enhancement bonus from a ranged weapon does not stack with the enhancement bonus from ammunition. Only the higher of the two enhancement bonuses applies.
Ammunition fired from a projectile weapon with an enhancement bonus of +1 or higher is treated as a magic weapon for the purpose of overcoming damage reduction. Similarly, ammunition fired from a projectile weapon with an alignment gains the alignment of that projectile weapon (in addition to any alignment it may already have).
When a magic arrow, crossbow bolt, shuriken, sling bullet, or other piece of ammunition misses its target, there is a 50% chance it breaks or otherwise is rendered useless.Ammunition that hits its target is destroyed.
Special Abilities
Special abilities have a variable point cost which counts towards its total weapon bonus. A weapon need not possess an enhancement bonus to have special abilities added to it.
Additional Damage Dice
Some special abilities add additional dice of damage. Unlike other modifiers to damage, additional dice of damage are not multiplied when the attacker scores a critical hit.
Activation
Usually a character benefits from a magic weapon in the same way a character benefits from a mundane weapon—by attacking with it. A weapon’s enhancement bonus is always active and cannot normally be deactivated.
If a weapon has a special ability that the user needs to activate then the user usually needs to utter a command word (a standard action), after which the ability remains active until the character repeats the command word to deactivate it. Some special abilities have alternative activation methods, which are described with that ability.
Light Generation
Fully 30% of magic weapons shed light equivalent to a light spell (bright light in a 20-foot radius, shadowy light in a 40-foot radius). These glowing weapons are quite obviously magical. Such a weapon can’t be concealed when drawn, nor can its light be shut off. Some of the specific weapons detailed below always or never glow, as defined in their descriptions.
Magic Weapons and Critical Hits
The enhancement bonus to damage adds to the weapon’s base damage and is multiplied as normal on a critical hit.
Some weapon qualities and some specific weapons have an extra effect on a critical hit. These special effects function against creatures not subject to critical hits, such as undead, elementals, and constructs. When fighting against such creatures, roll for critical hits as you would against humanoids or any other creature subject to critical hits. On a successful critical roll, apply the special effect, but do not multiply the weapon’s regular damage.