3e SRD:Psionic Weapon
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Psionic Weapon [Psionic]
Prerequisite: Str 13+, Power Attack.
Benefit: The characters melee weapon deals +1d4 points of damage (slashing, piercing, or bludgeoning, as appropriate to the weapon) when the character pays the cost of 1 power point. The character must decide whether or not to pay the cost prior to making the melee attack. The weapon remains for a maximum number of rounds equal to the characters Strength modifier +1, or until he or she makes his or her next attack, whichever occurs first. If the attack misses, the power point expenditure is wasted.