Gauntlet III: The Final Quest is a home computer game by U.S. Gold and Tengen it was released in 1991. A land called Capra was having many wars  among its kingdoms; peace would come but then another war would start. Then one day a wizard named Magnus came and brought peace, but to make sure there would never be another war he created a door to the dark dimensions from which evil things would come, if there was ever another war: "This be the Final Peace for if it is broken, all Capra will be at the mercy of the devourers". Then the Velcrons came to these kingdoms. They were servants of the things behind the door. They took over the magic kingdom and their king, Capricorn, held the wizard as his captive. Evil slowly came from this magic kingdom, bringing plagues, and even poisoning the food. The people of these lands begin to hate, and the peace was threatened. Eight champions have come to try and put an end to the darkness covering their land.

Three disk set.

Reference: Wikipedia