Casilis was a barren, desolate planet. It contained little water and little vegetation, making it rather unsuitable for life. It contained rare resources, however, the main one being ores. During the Cruentusian War, the Srav Federation found the ores, and set up a base on the planet to collect them. However, the Necasian Military found the Srav base and, along with the Savi Alliance, destroyed the base. The Necasians then set up a base of their own on the planet.