The excluder has three power settings - low power (2D), normal power (4D), and high power (6D). Each setting forms a protective "sphere" with a diameter of 10 72meters, 20 meters and 40 meters, respectively. Every round that a creature possessing senses in the affected range attempts to approach, it must make a willpower or Strength roll (whichever is higher) against the excluder's power setting to remain within the device's range. Failure means the creature retreats as far as it can until it is out of range; success means it can advance but suffers -2D to all actions due to irritation and distraction. Attempting to corner a creature, however, is not a wise move, as full flight-or-fight instincts remain in affected creatures.