Grubba is a character similar to Tubba Blubba. He is in charge of the Glitz Pit, an arena for fighters. He built a machine, powered by a Crystal Star, to sap the energy from fighters and transfer it into his own body to make him stay strong, healthy and youthful. He used it to make the former Glitzville champion, Prince Mush, disappear when he finds out about Grubba's machine. He hires Mario to be a new fighter, naming him "The Great Gonzales." Jolene, Grubba's assistant, comes to Glitzville to find out what happened to her brother, Mush, and he hires her without suspecting she was spying on him. While working up the ranks, he sends hate mail to Mario as he gets closer to discovering his secret. Mario finds out about Grubba's use of the Crystal Star and faced him. Grubba uses the machine to become a supercharged monster, calling himself "Macho Grubba" and fights Mario. Despite his supercharged strength, he is defeated and reverts back to his normal self. Jolene confronts the defeated Grubba, demanding to know what happened to Mush. He reveals how he made him disappear using the machine, and Mush is returned with the power of the Crystal Star. Jolene takes Grubba's place as promoter. No one knows what happened to him afterwards.