Game Genie (Mega Drive)

Accessory Program
Game Genie
Made for: Sega Mega Drive
Manufacturer: Codemasters
Distributor: Galoob (US), Camerica (CA), Hornby (UK)
Release Date RRP Code

The Sega Mega Drive version of the Game Genie is a specialised "cheat cartridge" (or "video game enhancers") developed by Codemasters for the which allows the user to manipulate video games.

Though developed by Codemasters, distribution was handled by Camerica in Canada and Galoob in the United States (and Europe, with the help of third-party distributors). Following the controversy of a Nintendo Entertainment System version of the device - of which Nintendo unsuccessfully tried to block, the Mega Drive (and Game Gear enhancer) were adopted by Sega as officially licensed products.

The Game Genie brand has since been discontinued, however the idea lived on through Action Replay and GameShark hacking devices on newer consoles in the years which followed. Game Genie codes have since become a supported feature in most emulators.

Operation

The Game Genie attaches to the end of a cartridge and is then inserted into the cartridge port of the console for which it was designed.

Upon starting the console, the player may enter a series of characters referred to as a "code" or several such series 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 cannot manipulate RAM, though it can make the console read different values from SRAM.

Because they patch the program code of a game, Game Genie codes are sometimes referred to as patch codes. These codes can have a variety of effects. The most popular codes give the player some form of invulnerability, infinite ammunition, level skipping, or other modifications that allow the player to be more powerful than intended by the developers. In rare cases, codes even unlock hidden game features that developers had scrapped and rendered unreachable in normal play (an example of this is the final Hidden Palace Zone in Sonic 2).

The Game Genie was usually sold with a small booklet of discovered codes for use with the system. However, these booklets would eventually become inadequate as new codes were discovered and new games were released that were not covered. To address this, an update system was implemented, where subscribers would receive quarterly booklet updates for a fee. In addition Galoob also ran ads in certain gaming publications (such as GamePro) that featured codes for newer games. Today, these codes and many others discovered by players can be found for free online.

On the Sega Mega Drive, the Game Genie can function as a country converter and bypass the TMSS (TradeMark Security System) since most of these games are only "locked" to their respective regions by the shape of the cartridges and a set of a few bytes in the header of the ROM. In other cases Game Genie codes can be entered to allow a game to be played on any region console.

Scrapped Successor

A new set of Game Genies called "Game Genie 2" were in the works in 1993 which would store codes and not require codes to be entered each time booting up the system. It was also going to have code searching features similar to the Pro Action Replay. This means it could probably alter RAM as searching for codes that affect ROM would have been more difficult. Due to some Game Genies recently being released it was decided to hold off the release of the new version till at least the following year but wound up being scrapped instead.

Official Code Books

In the US, Galoob offered a subscription service in which "code updates" would be sent to Game Genie owners quarterly over the course of a year. Generally these books were released to cover new games, i.e. software released after the Game Genie's launch. This service was not unique to Sega console owners. Later Game Genie releases incorporated the codes from these books into the codebook which shipped with the cartridge.

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  Volume 1, No. 1

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  Volume 1, No. 2

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  Volume 1, No. 3

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  Volume 1, No. 4

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  Volume 2, No. 1

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  Volume 2, No. 2

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  Volume 2, No. 3

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  Volume 2, No. 4

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  Volume 3, No. 1

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  Volume 3, No. 2

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  Volume 3, No. 3

Magazine articles

Main article: Game Genie (Mega Drive)/Magazine articles.

Promotional material

• GameGenie MD UK PrintAd.jpg

  UK print advert

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  BR print advert

Print advert in Electronic Gaming Monthly (US) #39: "October 1992" (1992-xx-xx)
also published in:

• Sega Visions (US) #10: "November/December 1992" (1992-xx-xx)

Print advert in GamePro (US) #57: "April 1994" (1994-xx-xx)

Print advert in Mega Force (FR) #12: "Décembre 1992" (1992-1x-xx)
also published in:

• Mega Force (FR) #13: "Janvier 1993" (199x-xx-xx)

Print advert in Mega Force (FR) #14: "Février 1993" (1993-0x-xx)
also published in:

• Mega Force (FR) #15: "Mars 1993" (1993-0x-xx)
• Mega Force (FR) #21: "Octobre 1993" (1993-10-08)

Print advert in Sega Force (SE) #1992-02: "2/92" (1992-11-19)

Physical scans

Mega Drive, US (older)
Cart

Mega Drive, US (version 2)
Cover
Cart

Mega Drive, US (version 3)
Cover
Cart

Mega Drive, UK
Cart

Mega Drive, UK (Extra Power)
Cover
Cart

Mega Drive, FR
Cart

Mega Drive, BR
Cover
Cart

Mega Drive, CA
Cart