Sera is the homeworld of the Locust and humans. It's a planet with a 26 hour cycle. Sera's surface consists of a few large continents and small island chains. Deep underground there exists a luminescent-like liquid substance known as Imulsion, which is used as fuel. beneath the surface of Sera exists The Hollow, which was unknown to the humans of Sera up until Emergence Day. The Hollow is the home of the Locust Horde and recently the Lambent.