Game Genie

The Game Genie is a line of cheat systems originally designed by Codemasters and sold by Camerica and Galoob. The first device in the series was released in 1990 for the Nintendo Entertainment System, with subsequent devices released for the Super NES, Game Boy, Genesis, and Game Gear. All the devices temporarily modify game data, allowing the player to cheat, manipulate various aspects of games, and sometimes access unused assets and functions. Five million units of the original Game Genie products were sold worldwide, and most video game console emulators feature Game Genie code support. Emulators that have Game Genie support also allow a near-unlimited number of codes to be entered whereas the actual products have a much smaller limit that usually tops between three and six codes.

In mid-1993 Codemasters began development on a "Game Genie 2", with Galoob again due to market and distribute the device in North America, but ultimately no Game Genie devices were released by Codemasters for the fifth generation of consoles. However, other companies have produced similar hacking devices such as the Code Breaker and GameShark. The Game Genie brand was later revived by the company Hyperkin, who released cheat systems for newer consoles.

The original Game Genie systems were pass-through devices that attached between a cartridge and the console. Upon starting the console, the player is presented with a menu that they can use to enter a series of characters referred to as a "code", that reference addresses in the ROM of the cartridge. Each code contains an integer value that is read by the system in place of the data actually present on the cartridge. The Game Genie is covered by US Patent #5112051, "Interfacing device for a computer games system", filed May 30, 1990. This patent expired on May 30, 2010, according to current US patent law.

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