The blorbs is a mysterious disease that appears in the events of Mario & Luigi: Bowser's Inside Story. In the game, the disease spreads all over the Mushroom Kingdom and infects the Toads, causing them to grow large and round and rendering them mostly immobile, though they apparently can roll uncontrollably. It is caused by Blorb Mushrooms that Fawful sold to several Toads, similar to how he sells the Vacuum Shroom to Bowser. The entire case of the blorbs is wiped out by the Miracle Cure, which is created after Mario and Luigi find and merge all three Star Cures.
Before the Miracle Cure eliminated the disease, blorbed Toads block several areas in Toad Town. Once the disease is cured, these areas are opened up to the player. A large percent of the infected Toads, including the one seen in the cutscene at the beginning of the game, are kept in one of the rooms of Toadley Clinic. After they are cured, one of the Toads still appears to have the blorbs, though speaking with him reveals that this is how he normally looks. This was likely done due to the "blorbed" Toad being one of the hiding places used by the Toad kid during the hide-and-seek side quest.
In Mario & Luigi: Bowser's Inside Story + Bowser Jr.'s Journey, some Goombas are also infected with the blorbs. It was also implied in the original game that Bowser's part of the kingdom may have been affected to some degree, as Bowser claimed that he "had every right" to participate in the meeting instead of being excluded from it. Thus, his intrusion was originally for the good of his followers instead of his single-minded desire for Peach. A cure is presented by the Best Fitness Friends via a chemical compound known as Skeletone Formula:D. Bowser Jr. sets off to find the ingredients for this compound after the last one has been used in a demonstration to cure a "blorbed" Goomba. Toward the end of the game, Bowser Jr. acquires enough Skeletone Formula:D to rescue his minions, as well as Bowser. Bowser however, despite the warning from his son to not drink too much, ingests too much of the formula and loses most of his body mass.
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