Space rocks/comets/meteoroids 'hurtle' at increasing speed and number, from left to right across the screen. Players have to destroy (by tapping) each rock before it disappears out of view (and impacts on Earth).

Points are awarded for each rock destroyed, with more points given for rocks travelling at higher speeds.

Any rock that survives its journey (i.e., manages to go out of view without being destroyed) will be counted as a 'miss'. The player is allowed 5 misses initially. This increases by 1 for each level that the player progresses. The game ends once the player has missed the allowed number of misses.

Take turns with your friends and relatives, and see who can score the highest! Can you hit more rocks than your grandmother?!