From the Super Mario Wiki, the Mario encyclopedia
The objective of the game is to blow into the mic of the Famicom controller to clear the game on screen. Unlike in Button Masher (a similar microgame), the Famicom controller was not replaced by a NES controller in localizations, since no NES controllers with built-in microphones were produced. Occasionally, Fronks appear to cross the screen on a tightrope, and the player should not blow.
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