Demoneye-X

Demoneye-X is a fixed-screen arcade shooter released by Irem in November 1981 on the company's M-27 hardware. The player's spaceship moves only left and right along the foot of the screen, firing missiles at space demons that mutate into a new form each time they are hit, passing from Demoneye-Jr to Octoplus to the Octobomb, which then tries to ram the ship. A stage ends only once the small demons are cleared and a hole opens beneath the Super-Demon, exposing a heart that must be shot, and a player who succeeds across two games in a row meets a three-eyed Demoneye-King whose heart takes three hits.