System: Arcadia

One of the original five worlds settled by the Exodus fleet in 2786, Arcadia superficially resembles its namesake. Though water covers only 50% of its surface, the planet supports considerable dense vegetation and a fully developed ecosystem. Many analogues to Terran flora exist on Arcadia, including the Arcadian mammoth, a large hairy herbivorous mammal with huge tusks and an extended snout, and the Arcadian russet, a mahogany-like hardwood. The world's colonists also introduced a number of Terran species, modified to survive Arcadia's environmental conditions. Most notable of these is the cloud cobra, which soon carved out a niche for itself in the misty equatorial jungles. The colonists also attempted to introduce the cobra to the temperate grasslands, but the native steel viper decimated the cobra nests within months of the cobras' release.

The presence of a harmful virus in the atmosphere caused many deaths among early colonists before the development of counter-agents. Some areas of the planet suffered earthquakes and intense volcanic activity; these were a source of many valuable minerals, prompting the establishment of extensive mining camps. Some particularly beautiful areas, such as the southern islands, became vacation resorts, while the rich soils of the Aeschal Plateau were ideal for growing genetically modified foodstuffs. Arcadia's relative abundance of resources had its downside, however. Considerable fighting took place on Arcadia in the Exodus Civil War, devastating most of the planet's cities and industrial centers. As farmers and workers were drafted into the armies of the petty warlords, the planetary economy collapsed, causing widespread famine and death.

Reconstruction took many years. As with Inner Sphere worlds devastated in the Succession Wars, the use of nuclear, chemical and biological weapons rendered many cities uninhabitable for centuries. The ruins of cities and military enclosures dot the Arcadian countryside. The planetary capital of Rivera was spared such destruction, and today serves as neutral ground for the three Clans present on Arcadia. A forth Clan, the Blood Spirits, withdrew to their colony world of York in 3059. Administrative and mercantile facilities occupy most of Rivera, along with the Hall of Arcadia. Made of local iron-rich granite, it serves as a meeting hall and houses the command mechanisms for the planetary SDS system. Aerospace bases on the world's single moon provided additional protection against attack.