Megatron causes his fellow Decepticons to be infected with the deadly Cosmic Rust. Perceptor is captured to find a cure and he does, learning that element X will do the job. The Decepticons are cured, but then they use Perceptor to spread the Cosmic Rust to the Autobots and element X is in short supply.

An alien is discovered to have a powerful weapon that fires crystals, which are taken from a creature Kup knows of, Chaos. Galvatron plans to construct his own powerful weapon on Chaos' home and several Autobots race to prevent him from using it on Cybertron.

Grimlock becomes a genius after trying to stop anti-electrons (released by Scukzoid and Slizardo) from causing disruptions in the new power generator. This proves very useful to the Autobots, especially when Grimlock learns Unicron is the source of the anti-electrons. The Autobots journey to Unicron to prevent more anti-electrons from being obtained, but Galvatron and his forces are also heading that way.