Action Replay is the brand name of a series of cheating devices created by Datel, primarily used for changing the behavior of video games and hacks. Currently, Action Replay is available for a number of consoles including the Nintendo 64 and Nintendo GameCube which feature games in the Super Smash Bros. series; a version for the Wii has been released as well.
 Nintendo 64 version
The version of Action Replay for the Nintendo 64 is inserted into the console's cartridge port. This version of Action Replay can be used to hack several features in Super Smash Bros., such as the debug menu.
 Nintendo GameCube version
The version of Action Replay for the Nintendo GameCube attaches to the console's memory card slot, which, along with a separate disc, enables the player to access a debug menu, among other things. This version of Action Replay can be used to hack several features in Super Smash Bros. Melee, including the debug mode, unlocking characters, infinite jumps, strange attacks variations, moveswapping (known for being very glitchy), and "super" codes which make attacks very fast. It can also be used to play with unplayable characters or on unplayable stages. The GameCube debug menu has been used for TAS videos.
Initially compatible with the Wii, current system updates of the Wii do not allow Action Replay for the GameCube to work; as a result, most TAS videos are now operated on either an original GameCube, or through the use of an emulator such as Dolphin.
 Wii version
While a version of Action Replay for Wii was officially released on August 15th of 2009, later system updates for the Wii have since caused it to become completely inoperable on the system; no official patch of any sort has been released by Datel to change this, and as a result, USB Gecko has now become the primary method to hack Brawl.