- Complete Monster:
- Unicron is a powerful and ancient Transformer who feeds upon worlds and the negative emotions of others. Disguising himself as one of Cybertron's moons, Unicron created the Mini-Cons to escalate the war between the Autobots and the Decepticons. Hoping to consume both sides once he regained enough power from their conflict, Unicron's plans were foiled when the Mini-Cons gained free will and abandoned Cybertron. Once fully awakened, Unicron attacked Cybertron, killed Starscream, and briefly stripped the Mini-Cons of their free will. After being defeated, Unicron returned by devouring the home world of Alpha Q and all of its inhabitants. When Megatron revived him, in hopes of turning him into a weapon, Unicron possessed Megatron and went off to destroy several planets that Alpha Q had managed to restore.
- The aforementioned Megatron, later known as Galvatron, is the brutal commander of the Decepticons. Desiring to destroy the Autobots and conquer the universe, Megatron enslaves Mini-Cons, tries to kill the Autobots' human allies, and tries destroy Earth with the Hydra Cannon. Upon his resurrection, Megatron leads his forces in destructive raids for Energon. Megatron plans to use the element to revive Unicron and use him as a weapon. Megatron uses Unicron's power to subvert the wills of his followers, notably enslaving Scorponok and Starscream. Developing a god complex, Megatron seeks to use the Cyber Planet Keys to accelerate the Unicron Singularity's expansion to end reality and reconstruct it in his own image.
YMMV / Unicron Trilogy