The Autobots are the heroes in the Transformers toyline and related spin-off comics and cartoons. Their main leader is Optimus Prime, but other "Primes" have also commanded the Autobots such as Rodimus Prime. They are constantly at war with the Decepticons. In the U.S. cartoon line, the Autobots were the descendants of a line of robots created as consumer goods by the Quintessons; the Decepticons, are descended instead from robots designed as military hardware. Other terms for the Autobots are Autorobots, Autoboterna, Kibery, and Robotrikim.
The Decepticons are the enemies of the Autobots, and the villains in the fictional universe of the movie and cartoTransformers toyline and related spin-off comics and cartoons. Their best own leader is Megatron. Other terms for the Decepticons are Décepticans, Destructors, Bedragarna, Bedragoner, Shakranikim and Álca.
Nebulans are aliens from the planet Nebulos who co-operate with the Transformers. Some Nebulans have allied with the Autobots, others with the Decepticons. The Nebulans' first and last appearance was in the three-part episode The Rebirth, which was intended as the pilot episode of the fourth season, but ended up being the season's only episode and the last episode in the entire series.
Headmasters
The Nebulans who co-operate with the Headmasters transform into the Transformers' heads.
Targetmasters
The Nebulans who co-operate with the Targetmasters transform into the Transformers' weapons.
Other characters
City-bots components
Mini-Cassettes
Cassette warriors are tiny Transformers; they are no taller than the humans. Their alternate mode is that of a microcassette. According to The Transformers' version, in the days of Megatron, Decepticons developed the art of espionage using cassette technology. Their first cassette, Laserbeak, could fly undetected into any Autobot stronghold, record information and then return to base. Then the Decepticons decided to increase their spyingabilities with Ratbat. As a bat, Ratbat can hide in crevices that Laserbeak cannot reach, and is especially effective in tunnels, caves or in the darkness of space. Ratbat records from the Autobots' most carefully guarded secrets. The Autobots had no choice but to strike back with these Decepticon techniques of stealth, building their own force of cassette Transformers, with Blaster as their guardian. They constructed Ramhorn, the rhino, who can use animalistic force if cornered, and Steeljaw, the lion, who can crawl through the foliage of any alien world, to sneak up on Decepticons. They also bolstered their cassette force with Rewind and Eject, who can transform to robot mode and use more conventional fighting force techniques. The alternate version of the Cassette warriors' origin is stated in the animated series. According to this version, they were once created by the divine inventor Primacron.
