Answer:
Virtual Console and WiiWare games available for download on the Wii Shop Channel are published by many different companies. Because each console and game can have their own unique controller needs, it is important to understand what the controller requirements are before downloading a game.
When browsing games on the Wii Shop Channel, the game being browsed will show which controllers are compatible. Please make sure to have at least one of the controllers that are shown when clicking "View Compatible Controllers" on the game's page of the Wii Shop Channel, as a compatible controller type must be used to play Virtual Console and WiiWare games.
The following controller icons can appear in the Wii Shop:
Wii-Remote: When held horizontally, the Wii Remote is a great way to play NES and other compatible games.
Classic Controller (sold separately): The Classic Controller and Classic Controller Pro attach to the Wii Remote and can enable play for many different game types.
Nintendo GameCube Controller (sold separately): Inserting a Nintendo GameCube Controller or Wave Bird wireless controller into the available controller slots on the system will enable game play for many types of games.
Note: Only Wii consoles with model number RVL-001 are compatible with Nintendo GameCube controllers. (learn more)
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