Assault City is a light gun, rail shooter released for Sega Master System in the year 1990. The player controls the role of Joe. He is the one of the last humans remaining that can overturn the robot regime. Nothing can stop him from destroying the control system which forces the robots to kill.
In the latter half of the 21st century, robots have been engaged in labor in dangerous places, housework, etc. Then suddenly, the control system used to function these robots plotted a revolt against the human race, and ordered every robot to annihilate all of the people. The robots robbed them of their weapons, and occupied various military bases and factories. The war robots that were manufactured there murdered men one after another, and the survivors organized a resistance and went into a full-scale offensive against the enemy's army.
Source: Wikipedia, "Assault City", available under the CC-BY-SA License.