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Improved Critical (Combat)
Attacks made with your chosen weapon are quite deadly.
Prerequisite: Proficient with weapon, base attack bonus +8.
Benefit: When using the weapon you selected, your threat range is doubled.
Special: You can gain Improved Critical multiple times. The effects do not stack. Each time you take the feat, it applies to a new type of weapon.
This effect doesn't stack with any other effect that expands the threat range of a weapon.