Breakdown is kind of a nervous wreck. Ever since the other Stunticons were put in stasis after a pitched battle with Defensor, his standing in the Decepticon army has plummeted. He's afraid that without Menasor, he's nothing, and that the only reason Galvatron hasn't destroyed him yet is because the Decepticon leader can't remember who he is. He's journeyed to Earth hoping to track down and eliminate Streetwise, the last functioning Protectobot. If he can get revenge, he'll have proven his worth. Clench made Breakdown a Forestonite test subject because he was considered completely disposable. The mutation enchanced Breakdown's sonic vibration ability, enabling him to focus and project powerful sonic booms from his robot-mode arms.