Dig Dug

Dig Dug is single screen action game in which the 
player must dig horizontal and vertical tunnels to 
reach and eliminate the underground-dwelling monsters
living there. This is achieved by either inflating 
them with an air pump until they explode, or by 
dropping rocks onto them.

There are two kinds of enemies in the game; 'Pookas'
(red monsters) and 'Fygars' (green dragons). Monsters
are initially trapped in caves and can escape in one
of two ways: Dig Dug can dig them out, after which 
they will immediately start chasing the player, but 
after the set time monsters can also escape a cave 
by turning into ghosts.

Developed by Namco