Dig Dug is a 1-2 player arcade game where you use your shovel to dig through the earth. Pooka and Fygar monsters are chasing you, trying to stop you from digging. Your only weapon is an air pump, which you can use to inflate them until they explode. You can also use rocks scattered throughout the earth to squash them. If the monsters aren't found for a few seconds, they turn into ghosts that can walk through the earth and are invincible.
The gameplay involves digging tunnels and avoiding the monsters while using your air pump and rocks to defeat them. As you dig, vegetables will appear in the center of each level, and collecting these will give you points. Your goal is to clear the levels without getting caught by the monsters or running out of oxygen.