The game involved the player flying a small fighter spaceship called a "Novaray Hyperfighter" and attacking a much larger and heavily armed vessels, the Dreadnaughts. Each Dreadnaught approached the "Galactic Unstable Energy Field," which acted as a defensive line. The goal of the player was to disable or destroy each Dreadnaught before it could reach the Energy Field and launch its missile silos on the planets the player is entrusted with defending.
As the game progressed, the player could make repeated passes over the Dreadnaught, one fighter at a time, attempting to weaken its defenses, slow its progress, and finally destroy it. Each Dreadnaught could be destroyed by bombing all of its energy vents, which would cause the Dreadnaught to overheat and be destroyed. Destroying its engines would slow its progress to the Field, and destroying its bridges would result in a diminished ability of the Dreadnaught to return fire.
To defend itself against the player's fighter, the Dreadnaught could fire various types of cannon and missile launchers; these could be destroyed to prevent them from firing on future passes. If all of a Dreadnaught's silos are destroyed, then even if it reaches the Field, it does not pose a threat, but still must be destroyed before the player runs out of fighters. As soon as a Dreadnaught was destroyed, another Dreadnaught of a different design would show up and need to be attacked. There were several different dreadnaught designs, and in later waves, multiple dreadnaughts would need to be attacked.