The Decepticons are one of the the primary factions in the Transfomers film series. They are typically concerned with galaxy domination, defeating the Autobots, developing new weapons, amassing large amounts of Energon, and basically beating people up. Not in that order. Unlike the Autobots, whose leader is a Prime bearing a Matrix, the Decepticons are led by the most powerful of their ranks. This tends to conflict, given how everyone thinks they're the most powerful. Also, the Decepticons are not excatly the most compassinate beings in the universe, but not all fight for greed. More than a few have a sense of honor, while others beleive that Cybertron would better be protected by agressive expansion. Ultimately, the Decepticons desire to protect their homeworld. In the film series, the Decepticons are Transformers who joined Lord High Protector Megatron to seize control of the AllSpark. Their numbers raised from Starscream to Blackout to Brawl to Frenzy to Bonecrusher. The Decepticons overwhelmed with the peace-loving Autobots, and Optimus Prime yet made the decision to launch the AllSpark into deep space. Megatron obsessively followed after it, and dissapeared. Starscream took over leadership, and began a search for Megatron and the AllSpark. After a while, Starscream began to focuse more on the AllSpark, hoping that Megatron would stay lost, something that the other Decepticons began to suspect. It was later revealed that The Fallen manipulated Megatron into forming the Decepticons. The Decepticons, in general, are less human in appearance than the Autobots in the movie, resembling carnivorous mammals, birds, insects, or the Decepticon symbol itself. What is also most noticable is that the Decepticons in the movie franchise are designed to resemble the Decepticon insignia itself, such as Blackout, Barricade, and Megatron.