Somewhere in the swirling gases of space lies a formerly proud world in utter ruin. It was the aliens. They came in droves, raining bombs, missiles, napalm, and fire. Planet Earth became known as Dust World. Destruction of life and property wasn't enough for the hostile creatures; they wanted complete control. They took the remaining human beings as their captors, enslaving them in a life of misery and humiliation. Only two men can change the fate of humanity. Raised as warriors from the time of birth, these men are the Nameless Ones.

Forgotten Worlds features two characters known as The Nameless Ones, who both look like Arnold Schwarzenegger, one even has a mohawk. It's their job to rid the planet of the attacking aliens.

As a Nameless One you must fly through three worlds (which equal seven levels) of alien-shooting chaos. Most of the action moves from left to right; within those confines, your character can shoot and fly in all directions.

Using weapons such as a balcan cannon, a burner, and a homing laser, you'll blow away a wide variety of alien creatures before you make it to the Tower of Dread. This level has you ascend a tower to the game's final boss, the mighty War Tyrant. As you progress through the game, you'll need to pick up money (called Zenny) whenever you see it. You can use it to buy weapons, armor, health, power-ups, and resurrection potion, which revives your life if you die.

A two-player mode features simultaneous cooperative action.