Action Replay (Mega Drive)

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ActionReplay MD.jpg

ActionReplay MD title.png

Action Replay
Made for: Sega Mega Drive
Manufacturer: Datel
Type: Cheat tool
Release Date RRP Code
Sega Mega Drive
Sega Mega Drive
Sega Mega Drive
DM 149.00149.00[7]
Sega Mega Drive
Sega Mega Drive
Sega Mega Drive

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Action Replay is a cheat device created for the Sega Mega Drive. It was originally released by Datel in the United Kingdom in late 1991, and was the latest in a line of cheat devices which continue to this day.

The Mega Drive Action Replay was the first cheat device to be released for the console, pre-dating the Game Genie by the best part of a year. Unlike the Game Genie, however, no Action Replay cartridges were ever licensed or endorsed by Sega, though unlike rivals Nintendo, the company did not actively seek to prevent such devices from being sold.


All Mega Drive Action Replays are cheat cartridges that act as a passthrough between the Mega Drive console and game cartridge, and when activated, can permanently set memory addresses to specified values, thus potentially altering gameplay. As a side-effect of this design, Action Replays also act as region converters, allowing Japanese games to be played on Western systems (likely a key part of its success in Europe).

Unlike the Game Genie which converts memory addresses and values into more human-readable codes, Action Replay codes are just memory addresses (represented in hexadecimal) followed by a value, albeit formatted in such a way to make it less obvious. For example, the Action Replay code FFFFE 00001 (which enables the level select in Sonic the Hedgehog) sets the value at memory address 00FFFFE0 to 1. Some emulators which support Action Replay codes expect a format that more easily reflects this, e.g. FFFFE0:0001 or even just FFFFE0:1.

Unlike its Game Gear and Master System counterparts the Mega Drive Action Replay was released in North America, though was unable to find the same level of success as the Game Genie.


A few different models of the Action Replay were released during the early 1990s:

Action Replay

The original Action Replay cartridge was released in late 1991, and allowed for up to four codes to be enabled at a time.

Pro Version Action Replay/Pro Action Replay

Early 1992 saw an enhanced version of the cartridge be released, which ups the code limit to twenty and includes a "trainer", which can be used monitor changes in RAM and to "find" compatible Action Replay codes. This change means the switch on the side now has three positions; codes on (top), codes off (middle) and trainer (bottom).

Datel also also provided a cheat book containing game codes with this version.

Pro Action Replay 2

The last revision in 1994 sets the code limit to 100, and has a selection of cheat codes built-in to the cartridge, negating the need to input them every time. It is also able to trick the game into thinking it is running on a specific region of Mega Drive console, thus acting as a fully-fledged region converter (though only for those with PAL consoles, as the device was only sold in Europe).

Code list scans

Magazine articles

Main article: Action Replay (Mega Drive)/Magazine articles.

Promotional material

Main article: Action Replay (Mega Drive)/Promotional material.

Photo gallery

Physical scans

Sega Retro Average 
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Sega Retro Average 
Publication Version Score
MegaTech (UK)
Sega Power (UK)
Sega Mega Drive
Based on
2 reviews

Action Replay (Mega Drive)

Mega Drive, US
ActionReplay MD US Box.jpg
Mega Drive, US (Pro Version)
ProVersionActionReplay MD US Box.jpg
Mega Drive, UK
ActionReplay MD Box MegaDrive.jpg
Mega Drive, UK (alt?)
ActionReplay EU MD box.jpg
Mega Drive, UK (Pro Version)
ProVersionActionReplay MD Box MegaDrive.jpg
Mega Drive, UK (Pro Version; alt)
ProVersionActionReplayPro MD EU Box.jpg
Mega Drive, UK (Pro Version; alt 2)
ProVersionActionReplay MD UK Box Alt.jpg
Mega Drive, UK (Pro)
ProActionReplay MD UK Box.jpg
Mega Drive, UK (Pro; alt)
ProActionReplay MD UK Box Alt.jpg
ProActionReplay MD Cart.jpg
Pro Action Replay MD EU Manual.jpg
Pro Action Replay MD UK Code Book.jpg
Code Book
Mega Drive, UK (Pro 2)
ProActionReplay2 MD EU boxfront.jpg
Mega Drive, DE (Pro)
ProActionReplay MD DE Box Black.jpg
Mega Drive, DE (Pro; alt)
ProActionReplay MD DE Box.jpg
Mega Drive, DE (Pro 2)
ProActionReplay2 MD DE Box.jpg
Mega Drive, ES (Pro)
ProActionReplay MD ES Box.jpg
Mega Drive, EU (Pro)
ProActionReplay MD EU Box.jpg


Sega Mega Drive cheat code devices
(Pro) Action Replay | Game Genie | Game Wizard | Genipak | Magicard | Vzlomshchik Kodov
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