Billy Cranston (Rebirth)

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.

He is also the teacher of Kevin Raymond and Lucy Mason, and serves as a father figure and mentor to both of them. Once he learns Kevin is a Blue Ranger, he is surprised to see it as well. Along with the retired rangers, he decides to prepare the new team for what is about to come.

Despite having very little powers left, he joins the rangers of old and new in the second coming of the Malastarians. Along with the rangers of old he fights against Onox and is triumphant, but in the process of overusing his powers like all the rest, he loses them.

After Fyrus' destruction, he also passes on the rules of Zordon.