The Super Game Boy launched in June 1994 at $59.99 / £49.99.
The Super Game Boy 2 launched on January 30, 1998 only ever in Japan.
Super Game Boy is a special cartridge produced by Nintendo for the Super Nintendo Entertainment System that allows users to play Game Boy titles on a television screen through an SNES. The device features a slot into which Game Boy games can be inserted. All original Game Boy cartridges can be played through Super Game Boy, which contains several default four-color palettes that can be selected to "colorize" the Game Boy's originally-monochrome software titles. Many Game Boy games also utilized Super Game Boy for special effects or upgrades such as enhanced music, voice clips, extra multiplayer functionality, custom frame borders or color palettes, or even new control schemes. Player-created custom borders can be drawn with a cursor, either by using the SNES controller's directional pad or the SNES Mouse.
While the device's internals are functionally identical to the hardware used in an original Game Boy, a game's programming and audio play approximately 2.4% faster on Super Game Boy due to a timing issue caused by the Super Nintendo's internal clock speed. Most Game Boy Color games are not compatible with Super Game Boy; however, certain GBC titles such as Pokémon Gold/Silver were designed to support backwards-compatibility with original Game Boy hardware, which allows these specific games to function normally on Super Game Boy.
Although most Super Game Boy-compatible titles featured only minor enhancements, Taito's 1994 release of Space Invaders for Game Boy (itself an update to the 1990 Japan-only Game Boy release of Space Invaders) contains a unique "Arcade Mode" only accessible on Super Game Boy. When this mode is selected, the game reboots into a special remake of two of the original arcade versions of Space Invaders, complete with 16-bit color graphics and transparency effects. This mode also uses the SNES's full screen resolution as opposed to the bordered presentation of all other Super Game Boy-compatible titles, essentially lending Space Invaders' Arcade Mode the appearance of a game programmed specifically for the SNES.
A revised version of the device called "Super Game Boy 2" was released exclusively in Japan in 1998. This updated hardware included a Game Link Cable port to support link cable-based multiplayer functionality such as the monster-trading mechanic used in Pokémon titles. Two colored LED indicators for power and link cable activity were also added, as well as eight new default borders. Super Game Boy 2 also corrects the slight timing issue that affected the original Super Game Boy.
In 1994, around the release of the Super Game Boy, Nintendo released a companion book entitled Super Game Boy Player's Guide. The book was part of a promotion from Nintendo where they sent it to subscribers of Nintendo Power. The book chronicles the features of Super Game Boy, including game-specific enhancements.