You can stop foes that try to move past you.
When a foe provokes an attack of opportunity due to moving through your adjacent squares, you can make a combat maneuver check as your attack of opportunity. If successful, the enemy cannot move for the rest of his turn. An enemy can still take the rest of his action, but cannot move. This feat also applies to any creature that attempts to move from a square that is adjacent to you if such movement provokes an attack of opportunity.
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SECTION 15