Billy Cranston is the former Blue Mighty Morphin Ranger and also a well known scientist and high school science teacher. He is a survivor and veteran of the First Malastarian War and also one of the retired rangers who later returns in his role to aid the new rangers in the Second Malastarian War. Like all the other rangers, he refused to be part of the Global Army since the Power Rangers only fight for the preservation of Earth and all life, not for flag, country or government. After Fyrus' destruction, he also passes on the rules of Zordon.