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[edit] Challenge mode

To unlock this mode, get past the 3000 meter mark in Marathon mode.

[edit] Time Attack mode

To unlock this mode, get more than 300 points in Score Attack mode.

[edit] Balloon-popping mini-game

To unlock the Balloon Popping mini-game, just get the top score on each single player mode. To start the minigame, tap one of the floating balloons that appear in the background of the title screen.

How to play: simply try to pop as many balloons as possible within the time limit. Continuously popping balloons of similar color yield more points.