Rule(s): Rules specify the effects of the execution of an action. They modify the objects attributes that participated in the action. Each rule identifies the time of its execution, which can be: trigger, destroyer, or continuous. Trigger rules will be executed at the time the action is triggered. Destroyer rules will be executed when the action is destroyed. Continuous rules, on the other hand, will be fired every clock tick, representing continuous behaviors of the model. Rules also specify the order they will be executed through the “priority” parameter.