Bonecrusher

Bonecrusher, also known as The Claw of Megatron, is a Transformer that can be described with one word: Hate. While other Decepticons get by on greed, ambition, or just their fondness for dispensing chaos, Bonecrusher is fueled by sheer, unrelenting hate. He hates everyone and everything, be they Autobot, Decepticon, or anything in-between—he even hates himself, revolted by his misshapen, hunchbacked robot mode, which he considers a reflection of all the ugliness and malice inside himself. The full force of this vicious cycle of hatred finds release in explosive frenzied bursts of psychotic brutality, as Bonecrusher takes out the full force of his bitterness and self-loathing on anyone who looks at him sideways. He hates that. He also hates Megatron, but would hate being terminated by the Decepticon leader more, so he sticks around.
On Cybertron, Bonecrusher was actually quite a skilled tactician—dedicated to the art of war, a fast thinker who could plough into battle while others were still mapping out strategy, and, most importantly in Megatron's eyes, a masterfully dirty fighter. However, Bonecrusher's skills left him consigned to a supervisory position and kept him off the battlefield, which, of course, he hated. Naturally, this only helped to increase his already epic levels of frustration and misery at his lot in life, until he became what he is today. He's so intensely pent-up that he'll unflinchingly take on opponents of any size—the bigger the better! Bonecrusher wouldn't hesitate to confront Optimus Prime head on, if he could.
He transforms into a Buffalo mine-clearing vehicle used by the military, perhaps because it was the vehicle he hated the least.