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Crippling Critical (Combat, Critical)
You are able to maim a target and hinder its movement.
Prerequisites: Critical Focus, base attack bonus +13.
Benefit: Whenever you score a critical hit against an opponent, its speed is halved for 1 minute. A successful Fortitude save reduces this duration to 1d4 rounds. The DC of this save is equal to 10 + your base attack bonus. Against creatures with multiple types of movement, you must choose which movement type to affect. A flying creature hit by this attack must make a DC 10 Fly check to remain airborne, and has its maneuverability reduced by one step.
Special: You can only apply the effects of one critical feat to a given critical hit unless you possess Critical Mastery.