The topographical map for the Startide IV game's primary planet "Elandra IV", which has been given such nicknames as "Eden" and "New Terra" but retains it's official classification for now. The planet is roughly the same size as Earth, but is in the process of moving from a methane/ silicon biosphere to an oxygen/ carbon biosphere, meaning that there are valleys and areas where the atmosphere has more methane then oxygen and is hazardous for colonists to tread without extra gear, and in some cases flammable or explosive.