Dig Dug is a 1-2 player arcade game in which you have to use your shovel to
dig your way through the earth. Stopping you from doing this are two monsters,
called Pooka and Fygar, who will continually chase you around. The only weapon
that you carry is an air pump, which you can use to inflate the monsters to
the point where they explode. (if you start to inflate them but stop doing so,
the monsters will get turned back to their normal selves). Furthermore, rocks
are scattered throughout the earth, and you can use these rocks to squash
them. If the monsters do not find you for several seconds, they will
eventually get turned into ghosts, which are able to walk through the earth.
They are invincible and cannot be killed. From time to time, vegetables will
appear in the center, and you can get these for points.

DIG DUG