The Transformers Season 2 Episode 45 Cosmic Rust ( Air Date 1985-12-25 ) Genre Animation, Kids, Action & Adventure, Sci-Fi & Fantasy category. Overview "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.".