Even in defeat, however, Zeta Prime had put one over on the Decepticons, as they took from him not the Omega Key, but the device that activated it.

Soundwave's interest in the clones caused Breakdown to deride him as a total nerdlinger, but he didn't have any words of mockery when Soundwave discerned the machine's weakness: a core that rapidly overheated and so had to open up to cool off. He was utilizing a vast machine that rendered him unassailable, allowed him to control portions of the ceiling so they dropped to crush anyone in the room, and generated an arbitrary number of energon clones bearing his likeness that battled savagely in melee combat. After utilizing Dark Energon bombers to blast their way into the Vaults, the squad came up against Zeta Prime himself. However, when Megatron told him in a paternalistic voice to 'try not to get crushed by the trains', Breakdown was confused, wondering aloud if his leader had made a joke. Breakdown seemed most comfortable during their time in the train tunnels, even challenging Soundwave to a race. When it turned out Zeta Prime had moved it, Megatron lead them on a run-and-gun mission through the city to the Vaults itself. Later, Breakdown joined Megatron and Soundwave in the invasion of Iacon, attacking the Stellar Galleries behind the Autobot's front lines in order to acquire the Omega Key. Breakdown was eventually defeated, and, true to his word, he joined the Decepticons.

Breakdown declared if Megatron could prove to be tougher than he was, then he'd join the Decepticons. When Megatron and his Decepticons destroyed a dam they had been using, Breakdown confronted them.

Transformers fall of cybertron weapons