The player controls a pair of disembodied lips, similar to a Chattery Teeth toy, named Mighty Mouth.
Various fast food menu items fly across the screen and the mouth earns points by catching them. The player must avoid eating the purple pickles. After eating 6 purple pickles, the screen is replaced by large text reading "BURP!", followed by "CLOSED". As the player acquires more points, the speed of the game increases. The transitions between speeds are indicated by the text "YOU'RE GETTING FATTER".