Kythirea occupies the third orbit in the heavens and is commonly referred to as "the Green Planet" for its coloration. The name is also apt for another reason largely unknown to any but sages learned about other worlds, for Kythirea is covered in lush jungles and other similarly plant-filled environments. In this respect, it is the mirror image of dying Areon, for Kythirea teems with life of all sorts.
In the past, travel to Kythirea by means of magical portals was far more common than it is today. Indeed, it is surmised that many plants and animals found elsewhere were originally native to the Green Planet, transplanted by sorcerers and scholars who found them useful. And of course the Eld also journeyed to Kythirea, though, lacking large supplies of azoth, it proved a less useful than originally hoped. The Red Elves did, however, warp some of Kythirea's native life to their own purposes, the most widespread example of which are the lizard men, which can now be found on many worlds.
At present, Kythirea is mostly cut off from the wider cosmos, as it has far less to offer the greedy and acquisitive than does Areon. Even so, there are tales of hidden wealth on the Green Planet -- ruined cities built by the Ancients or by reptilian inhabitants who rose to power eons before the Eld ever step foot here. Likewise, Kythirea's plants are reputed to have magical and medicinal uses, including, some say, the extension of Men's lives beyond their usual allotment. There is no proof of any of these legends and likely won't be for some time, since functioning portals to Kythirea are rare and, unlike Areon, there is, at present anyway, no pressing need to visit it.