A boy named Hiro Taikai randomly finds a tiny golden lighter in Zippo-style. The lighter transforms into the giant robot Golden Warrior Gold Lightan, who can just as easily return to the form of the lighter in order to be transported within Hiro's pockets. The Golden Warrior is a sentient robot who has been tasked with defending the planet Earth from an ongoing alien invasion. It challenges alien robots in single combat duels, and can disable them by pulling out and smashing their heart-box energy device. The Golden Warrior is allied with other transforming robots, such as Scope Lightan (who can locate an enemy's weak focal points) and Time Lightan (who can briefly freeze time).