The protagonist in Galactix is a bipedal alien of the green, stalk-eyed variety. This being has just crash-landed on a planet and, to his considerable dismay, discovered that his spaceship won't power on again. Your task is to guide the distraught xenomorph past the dangers of this inhospitable world, locate the five items required to repair the ship, and hopefully make it back out of this hellhole (in one piece).

Your makeshift prison is a flip-screen maze of interconnected rooms, inhabited by hostile locals who stand ready to dissuade you from your quest in person - being shot (or even touched) by them will deplete your life energy, and they respawn even after death when a room is re-entered. Although Galactix is basically a platform action game, the controls are somewhat atypical: walking, shooting and jumping have their own keys, but inventory-related actions must be selected from a menu, as in an adventure game. These include picking up, dropping, examining, using, and eating/drinking items, the player can carry up to five objects at a time. Appropriately, a scrolling message area gives descriptive verbal reports of your actions and their results. As a visual clue for your overall progress, your score is displayed as a percentage on a bar.