ZEM is a reoccurring name used in Zeroids/Robo Force lore. It was first used as the name of the original Ideal Zeroids toyline's flying saucer: ZEM XXI Zeroid Explorer Module. The name was brought back during the Ideal STAR Team toyline as the name of the team leader: ZEM-21. With the re-launch of Robo Force by Toyfinity the name has been given to the strange new partner Maxx Zero meets upon returning to Zeton: ZEM the Engima.
ZEM-21 is an expert at analyzing data and recording and made the plans for the small team. He displays curiosity, but shows no particular skill for fighting. This dangerous vigil of theirs is the job of Earth's STAR Team Scouts, such as ZEM-21 and his two Zeroid companions, the heroic crew of the saucer-ship Star Hawk! Zeroid Blue is programmed to be a mechanic and engineer as well as the pilot of the Star Hawk. It can quickly cross circuitry to cause an explosive overload. Zeroid Red is programmed to be the pilot and gunner while also armed with shock blasters. Together they use their small but nimble spaceship, Star Hawk, to patrol the system keeping the Knight of Darkness at bay.