Starscream

Starscream is the toadying lacky of Megatron, who is either his most loyal servant or his mortal enemy. Starscream will often lead the Decepticons into battle in the name of Megatron, but is constantly plotting his downfall. Megatron often sees right through Starscream's feeble plans but lets him get away with most of them because they amuse him so much.

Starscream is a reasonably  powerful foe for the Autobots, (apart, of course, from Optimus Prime). However, even some of the weaker Autobots cn still take him on in one-to-one combat and emerge victorious. Starscream is a coward at heart and will often flee battles even if he only takes minor damage.