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Pack Flanking (Teamwork)
You and your companion creature are adept at fighting together against foes.
Prerequisites: Int 13, Combat Expertise, ability to acquire an animal companion.
Benefit: When you and your companion creature have this feat, your companion creature is adjacent to you or sharing your square, and you both threaten the same opponent, you are both considered to be flanking that opponent, regardless of your actual positioning.
Normal: You must be positioned opposite an ally to flank an opponent.