A Conditional Action is an action that occurs only when a predetermined set of conditions are true. In game terms, this means that Conditional Actions allow characters to move and act when it's not their turn.
In order to have a conditional action, a character must declare it. This is an action that costs 2 AP and occupies one of the character's Combat Threads. This declaration must spell out what will trigger the action and what action or actions the character will perform once that trigger has occurred. A typical declaration would be: "If the mage starts casting a spell, I will shoot him with my bow." Or: "If the dragon breaths fire, I will run to safety."
Once the trigger for the Conditional Action has been met, the character who declared the action can complete the actions he specified. The character must spend the AP for those actions as per the actions' off-turn costs. If the character is unable to complete these actions, the Conditional Action is still considered used.
Once a Conditional Action has been triggered, the character must re-declair that Conditional Action if he wishes for it to continue existing.
If completing a declared action would cause the character harm, or if the character simply wishes to not act, the character may make a DC: 20 Awareness check and not complete the action. For example, if a character declared that if his opponent attacked him he would step back five feet and that character has his back to a ledge, the character would be allowed to make the Awareness check to not complete that action. The Conditional Action is still considered to be triggered.
Vagueness and GM Discretion
The triggers and character actions of a Conditional Action must be very precisely defined. Saying "If I am attacked" or "If he attacks me" is not good enough. More acceptable triggers include: "If he attacks me with his sword" or "If he tries to grapple me."
Likewise, saying that a character will "attack the person attacking me" isn't good enough. Instead, use "throw a dagger at him" or something equally specific.
As always, the GM reserves the right to overrule any declarations of Conditional Actions if he feels that they are too vague or if they are exploiting the game.