Unicron is a mechanical planet that devours entire worlds. He appeared in the 1986 film and has remained the biggest threat in almost every universe of the franchise ever since.
Primus's opposite
In most versions Unicron is a primal force of destruction, Primus's eternal brother and enemy. If Primus creates life, Unicron destroys it. According to the mythology, the Thirteen Primes were created precisely to fight him.
A villain beyond negotiation
Megatron can be understood, and a truce with him is possible. Not with Unicron. He doesn't want power or revenge; he's simply hungry. That's why in many stories Autobots and Decepticons are forced to unite against him, as in Armada or Prime.
A legendary voice
In the 1986 film Unicron was voiced by Orson Welles — the great director and actor's final role. His thunderous voice forever cemented Unicron as cosmic horror.
Modern appearances
In Prime Unicron sleeps at Earth's core and Dark Energon is his blood. In Rise of the Beasts he hunts the Transwarp Key to reach new worlds. And The Last Knight hints that Earth itself may be Unicron. More in his dossier in the Characters section.
