Mr Dig is based on the arcade game Mr. Do! where you have to collect all the cherries over various single screen levels to move to the next level. As you move through the tunnels or dig through the dirt there are various nasties chasing you, but they can only move through tunnels and can't dig. To stop them you can either throw a bouncing ball where only one can be thrown at a time, or remove the dirt below an apple and make it fall on top of them. If you are touched by a nasty then you lose one of five lives and when all are gone it's game over. Before you play you can select a skill level from 1 to 9.