Keen Critical (3.5e Feat)
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Keen Critical [Fighter]
You become even more adept at striking vital points of your enemies.
Prerequisite: Improved Critical, BAB +12
Benefit: Choose one type of weapon for which you have Improved Critical. When using this weapon your threat range is doubled.
Special: You can gain Keen Critical multiple times. The effects do not stack. Each time you take the feat, it applies to a new type of weapon. Unlike Improved Critical, this effect does stack with any other effect that expands the threat range of a weapon: in this case you apply the Keen Critical bonus after the other effects. A fighter may select Keen Critical as one of his fighter bonus feats