A defense roll represents a character’s attempts to avoid a strike from an opponent on the opponent’s turn in a round. When a character makes a defense roll, she rolls 1d20 and adds her Deflection Bonus or Dodge Bonus. If the result equals or beats the opponent’s Attack Roll, the character avoids the strike. Many modifiers can affect the defense roll.
When making a Defense Roll, the character can choose to use either her Deflection Bonus or Dodge Bonus. The bonus used depends on the type of Defense she is attempting.
Deflection: Deflecting an attack involves blocking it with a weapon, shield or other defense to avoid taking damage. When deflecting, the character’s Deflection Bonus is added to her Defense Roll. Deflecting is an immediate standard action. Some feats allow the character to deflect as an immediate free action. A character cannot make a Deflection defense roll against firearms and energy attacks.
Dodge: Dodging an attack involves moving out of the of an attack altogether to avoid taking damage. When dodging, the character’s Dodge Bonus is added to her Defense Roll. Deflecting is an immediate standard action. A character can make a Dodge defense roll against ranged attacks but she does so without a Dodge bonus and with an additional -4 penalty.
Combat Maneuver: A Combat Maneuver defense bonus is applied when performing certain actions, like disarm, as a defense.
A character cannot make a defense roll if she is flat-footed or flanked.