Transformers: Prime - Chaos Bringer
As Megatron’s brutality escalates, Optimus abandons diplomacy and prepares for a final reckoning. But the awakening of Unicron, the ancient Chaos-Bringer within Earth’s core, unleashes global devastation. Forced into an uneasy alliance, Autobots and Decepticons descend into the planet to stop him, facing impossible odds to prevent total annihilation.