A neologism used as a metaphor for human demand on the Earth's ecosystems. Galactus, a being from the Marvel Comics Universe, specifically the Fantastic Four books, consumes planets for their energy in order to sustain himself. He is often aided in this process by one of his heralds, the most famous among them being the Silver Surfer. The name of this Planet Killer is given to Galactus Syndrome; the exponential hunger for energy.