Balloon Kid is a platform game (more of a flying game, really) produced by Gunpei Yokoi, creator of Metroid and the Game Boy. It is a sequel to the NES game Balloon Fight.
The gameplay is similar to its predecessor's, but instead of a single-screen, Joust-like game; the player explores several automatically scrolling levels. This game is one of few side scrolling games which scroll exclusively to the left (Balloon Fight's Balloon Trip mode is another).
There have been two ports made of this game, one for the Japanese Family Computer and one for the Game Boy Color. The Famicom game stars Hello Kitty and has a larger play area, while the Game Boy Color game is mostly unchanged other than the addition of color and a save feature. These were only published in Japan, while the original Balloon Kid was only released in the US and Europe.