Cable | Nintendo GameCube | Game Boy Advance Connection Cable
Nintendo Game Cube
GameCube to Game Boy Advance link cable
The GameCube – Game Boy Advance link cable is a cable used to connect the Game Boy Advance (GBA) to the GameCube. The cable serves different functions with different games. These functions include unlocking additional content, turning the GBA into a second screen, turning the GBA into a separate controller, or transferring in-game items between related games. When used with the Game Boy Player accessory, the GBA can be used to control any Game Boy game played through the GameCube.
The cable has one end that plugs into a GameCube controller slot and another end that plugs into the GBA's extension port. The cable is compatible with the GameCube and the original Wii on the console side, and the Game Boy Advance, Game Boy Advance SP, Game Boy Player, and e-Reader on the portable side. Because the Game Boy Micro has a differently-shaped link port, the official cable does not work with it.
Read more about each game compatibility here