Zax only loves one thing, money. On one particular planet, he believes plenty of ore is available to dig up and sell, making him plenty of cash. However, while coming in to land, he is shot down. Zax soon discovers that two races populate the planet: The Korbos, a peaceful alien race and mechanical beasts led by their God, Om.
Using the high artificial intellegence on his ship Zelon, Zax must help the Korbos from total destruction, collect as much ore as possible, plus parts to fix his ship.
Zax: The Alien Hunter plays somewhat like the Crusader series. The player controls Zax's movement with the keyboard and his aim with the mouse. The aim movement is completely free, and Zax can shoot to a direction while moving to another different one. To use items, Zax needs only to touch them, and to collect items he needs only to step over them.
The ore collected can be used at Zax's ship for creating new items such as weapons, shields and batteries. The better the item, the more ore needed to create it. Each weapon and shield has its own energy bar, which is depleted as Zax shoots his weapons or gets hit. Energy orbs will be available as he kills enemies (orange orbs for shield energy, blue orbs for weapon energy). Besides the hand guns, Zax will also find auto turrets and companion drones.
Zax can also use portals to teleport himself to different locations on the map. Specific portals will lead him directly back to his ship.
This game can also be played by up to 16 people in three multiplayer modes: capture the flag, death match and "salvage king" (where the players must gather as much ore as they can).