Starscream

Starcream is the treacherous Decepticon (Destron in Japanese version) Air Commander and the deadliest of the Seekers (Jetrons in Japanese version). The self-proclaimed pride of the Cybertron War Academy, he's famous not only for his incredible skill, but also for his limitless (and troublesome) ambition. Starscream believes that he is more suited for command than Decepticon leader Megatron. Thankfully for Megatron, Starscream's mutinous, power-grabbing plots are almost always transparent, and he can never muster up enough patience to complete a grandiose power play. Even on the few times he has taken control of the Decepticons, he quickly loses control of a situation, but is too arrogant to realize when he's in over his head. He never learns from his mistakes, but then again, Megatron doesn't either, seeing as how he's never turned Starscream into slag. Despite his constant failures, Starscream believes it is only a matter of time before he prevails—his destiny is inevitable.

(Source: Transformers Wikia)