History
Sylus was an uninhabitable and minuscule mesoplanet, homeworld of jellyfish-like aliens. The planet was the former home of a race of long-dead war sorcerers, with their burial grounds rich in decomposing enchantments.[1] Sylus was one of five special planets found by the Silver Surfer whose rare and unique energies would give Galactus powers beyond imagination. With the arrival of the Black Winter, the Surfer gave the planets coordinates to Thor, who became Galactus's new herald.[2]
Its population was transported to Asgard by Thor's orders to allow Galactus to feed on and destroy the planet.[1]