I managed to get a GameBoy cartridge labelled "Pro Action Replay" today and was wondering how to use it. It's a grey cartridge that has a slot on it as well as a red button and a black slider switch. Here are some pics: The red button and black switch, the button resets the console I ve searched on Google and via GBAtemp's forums but haven't found any instruction manuals for it. It was tested on several consoles: Original GameBoy DMG - Boots GameBoy Pocket MGB - Boots GameBoy Color CGB - Boots to GameBoy logo, fails to progress any further Gameboy Advance AGB - Boots to GameBoy logo, fails to progress any further GameBoy Advance SP AGS001 - Boots to GameBoy logo, fails to progress any further Code entry screen? On the occasions that it does successfully boot, I can enter some kind of code entry screen and pressing Start will bring up a screen prompt for me to "slide poke switch". Tested using Action Replay codes with Pokémon Yellow, the game either boots without the cheat codes causing any effect, it boots to a corrupted title screen and freezes, or it enters the title screen only for a message to say that the save data has been destroyed and the game then runs like normal without any save data. Has anyone here used one before and knows how it works? Thanks.