From the Super Mario Wiki
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There is a woman with a long strand of mucus hanging out of her nose. The player must repeatedly mash the button to make the woman sniff the mucus back into her nose. If the player waits too long, the strand will get longer and eventually break off, causing the game to be lost.
WarioWare Gold replaces the woman with an older man for the second stage of the game. The third stage features both characters.
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