Pulsar © 1981 Sega.
Pulsar is a multi-directional shooter where the player must use a four-way joystick to direct a small white tank around changing mazes with a single button to make it fire shots at enemies. The yellow enemies move along the edges of the walls, while the green enemies move randomly and the red enemies bounce off the edges of the walls - and they all move faster, fire faster, and increase in point value, with every round. You should also watch out for "force-field" walls - they will kill your tank if it gets caught in one. If you shoot the Pulsar, it will explode into six enemies.
You will also have to collect the colored keys to open the numbered locks at the bottom of the maze - you will receive a double-points bonus if you do it in numerical order, but regardless of whether you opened those locks in numerical order or not, you will always receive a bonus for how much fuel you have left at this point. You will receive extra fuel when you kill enemies and open locks; running out will kill you.