Mario is the older brother of Luigi and formaly one of the most acclaimed heroes the land had ever seen. While he did switch to Ganon's side ever since then he was not the same person, he had no drive no reason to keep fighting to his fullest anymore. He spend most of his days day dreaming about the past. But one day a spark was awakened in his heart and he found something to fight for. if you're auditioning for this role you need to be able to sound completely pissed at the world as well as filled with confidence and determination as this character makes a total personality change mid way through the movie. Again no typical Mario voice as he needs to sound serious if you'd like refference take a listen to how he sounds in Tigura21's "Smash King" on Youtube