A new peripheral, known as the Gamecube Controller Adapter has been revealed, which unsurprisingly allows you to connect Gamecube controllers to the Wii U. The first game which has been confirmed to work with this device will of course be Super Smash Bros. for Wii U. The device even features four ports so no one will claim unfair advantage!
No other game’s have yet been revealed to be compatible but it would be wise to expect more to be confirmed at a later date. Nintendo have also yet to confirm release date or pricing information although we do know that Super Smash Bros. for Wii U is launching in Q4 2014. Nintendo will most likely launch the Gamecube Controller Adapter either before or alongside the game.