Balloon Kid is a flying platform game developed by Pax Softnica and published by Nintendo for the Game Boy on October 5, 1990 in North America and on January 31, 1991 in Europe. It is the sequel to Balloon Fight. It was never released in Japan for the original Game Boy; however, two years after its original release, a licensed Family Computer port titled Hello Kitty World (??? ??? ????) was reprogrammed and released by Sanrio's subsidiary Character Soft exclusively in Japan on March 27, 1992. A Game Boy Color edition with a few new features titled Balloon Fight GB (??????????) was released in Japan on July 31, 2000.