- "Get yerselves ready to...BAAAAAATTLE!"
- ― Grubba
Grubba (ガンス?) is a character in Paper Mario: The Thousand-Year Door. He ran a fighting ring in Glitzville, called the Glitz Pit. However, Grubba rigged the Glitz Pit, using the Crystal Star to fuel a machine that he used to boost his own strength. When he does so, he becomes Macho Grubba. He is also the original referee of this arena before Jolene took over his duties.
Grubba is a blue Clubba that wears a black and green vest with a black hat. He also wears shades, has orange hair, and his shell is purple.
Grubba creates a good-natured facade to mask and distract his concealed motivations that benefit himself at the expense of others. While on public and promoting the Glitz Pit, Grubba shows his public image: friendly and passionate about his life's work. Paper Mario: The Thousand-Year Door hints that Grubba's obsession with his image develops as a result of his fame. Originally, he has not cared about glitz and glamor, though later in life, Grubba feels nostalgic about what he once was and wants to relive those days, despite the costs. Despite this emotional transformation, Grubba retains an air of good sportsmanship throughout his life. Grubba encourages his fighters and did not mask his excitement for rising stars such as Mario. Even as he lay defeated, he commends Mario for a good fight. Due to the unethical use of the power-draining machine, this causes Grubba to keep the usage a secret and he uses the machine to his advantage to continue keeping it concealed. As Goombella realizes as soon as she met Grubba, he is a "super-greasy smooth talker" and not necessarily trustworthy, even while he maintains his facade. The text in the dialogue box hints at his possessing a heavy southern accent.
Grubba is first seen hosting a match between Rawk Hawk and The Koopinator. Rawk Hawk wins the match and Grubba awards Rawk Hawk with the Champ's Belt. Sooner or later, Mario enters his room and is happy to see another new challenger. He dubs Mario "The Great Gonzales" and sends him to the minor league room. After some time later, Grubba realizes that Mario is searching for the Crystal Star and sends a threatening mail to him. Grubba even suspects his assistant Jolene may be plotting against him as well. After Mario finds his blueprints in his drawer, he makes for the ring where he reveals that he sucked up all of the energy from the other fighters to keep himself younger and stronger. Using the Crystal Star, he then transforms into Macho Grubba and fights Mario. Mario defeats him and, after turning back to normal, Grubba reveals that he was also responsible for the disappearance of the last champ of the Glitz Pit: Prince Mush. However, Prince Mush suddenly emerges from the machine and Grubba is left there on the ground. It is unknown what became of Grubba after those events.
- There is a similarity between Tubba Blubba and Grubba. Both of them look similar to each other, have blue skin color, and are Chapter 3 bosses. Also, the names "Blubba" and "Grubba" sound similar to each other and they both belong to the Clubba family. Both have spikes on their shells, although regular Clubbas don't have spikes. Lastly, they both have a well-guarded secret to their "invincibility". Tubba Blubba got his by siding with Bowser while Grubba got his through the Power-draining machine. However while Tubba Blubba was motivated by the fact that he was bullied by the Boos, Grubba was motivated so he could stay young.
- The Stone Spikes in New Super Mario Bros. Wii also resemble Grubba.
- Grubba is one of the darkest villains in the Paper Mario series, due to him using a machine to drain the life force of other characters just to make himself look young.
- Aside from Cortez, Grubba is the only chapter villain to work independently of the X-Nauts or Shadow Queen, as well as not even being known to associate with them however unlike Cortez, he doesn't reform after his defeat.
- As such, Grubba is the first villain to be a solo threat in a Chapter.
- Grubba is the only chapter villain who used his Crystal Star the way it's supposed to be used, which would be the Power Lift special. All other chapter villains either possess a Crystal Star, but never use it, or simply obstruct the path to it.
- Grubba's power-draining methods could be a reference to real life celebrities who have abused their positions.