You have five lives in which to survive the bombing attacks of four separate flocks of Phoenix war birds who protect the alien spaceship. Your challenge is to eliminate the birds, get to the spaceship that follows the fourth wave of birds, and shoot the alien pilot. To eliminate the large, menacing Phoenixes of the third and fourth waves, you have to hit them in the center. If you only wing a Phoenix, like its ancient ancestor, it will soon regenerate the missing part and become a whole bird to attack you some more.
To destroy the alien pilot, you have to erode the multi-colored hull of the spaceship directly beneath the cockpit to create a clear shot at him. But one of the hull layers - the blue layer - rotates the length of the spaceship. So, you not only have to chip away at the blue layer, but you also have to time your shot at the alien to coincide with the hole passing directly under him.