As Nintendo announced a couple of weeks ago, you'll be able to play the Wii U Smash Bros. game with GameCube controllers using a new adapter peripheral they've created for their newest console.
The Wii U GameCube controller adapter will be out on the same day as Super Smash Bros., and it'll cost $20. There's also a special GameCube controller (that you can see above) for $30, and a bundle including the adapter, the controller, and Smash for $100.
Press release below:
Nintendo GameCube controller for Super Smash Bros.: Many Super Smash Bros. fans grew up playing Super Smash Bros. Melee for the Nintendo GameCube system, and some will always prefer that system's controller. The Nintendo GameCube controller also could be used in Super Smash Bros. Brawl for Wii. To honor that devoted loyalty to a classic way to play, Nintendo is introducing an adapter that lets up to four original Nintendo GameCube or WaveBird controllers work with Wii U. The adapter will be available at a suggested retail price of $19.99. Nintendo is also launching a retro Nintendo GameCube controller with Super Smash Bros. markings at a suggested retail price of $29.99. Additionally, Nintendo is offering a special bundle that includes Super Smash Bros. for Wii U, one special Nintendo GameCube controller and one adapter at a suggested retail price of $99.99. All of these items are scheduled to launch the same day as Super Smash Bros. for Wii U this holiday season.