Army Fighting (3.5e Feat)
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Army Fighting [Combat]
You are adept at fending off a horde of enemies.
Prerequisite: BaB +3, Combat Reflexes
Benefit: Enemies do not count as flanking you for the purposes of attack bonuses or abilities that affect flanking (such as sneak attack); In addition enemies do not automatically hit you with an attack roll of a natural 20 with melee or ranged attacks. Instead, they must compare their attack result to your armor class normally.
Normal: Enemies gain a flanking bonuses against you and automatically hit on a natural 20.