"You're going down!"
Leader-1 is the partner Mini-Con of the Decepticon
leader, Megatron. Leader-1 changes into a piece of self-propelled
artillery, capable of inflicting great damage on the Autobots. When
Leader-1 combines with Megatron, he becomes an extremely powerful
cannon, firing mega-powered blasts.
Bio and stats taken from the Transformers Armada Official Guidebook.