Optimus Prime, heroic leader of the benevolent Autobots, describes in a voice-over the collapse of the Transformers’ home world, Cybertron. It was destroyed by the malevolent Decepticon leader Megatron in his quest to get hold of the All Spark. The Autobots want to find the All Spark so they can use it to rebuild Cybertron and end the war between the Autobots and the Decepticons
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