Heiankyo Alien

The player controls a Heian period police officer who must defend the capital city from an alien invasion by digging holes in the ground and filling them back up after an alien falls inside. The player scores points for every alien trapped, and the quicker the hole is filled up after the alien falls in, the higher the number of points are scored. The aliens increase in number as the levels progress, and they can escape from holes after a certain period of time elapses or if a