Nimbus

Nimbus is tropical moon in Io's East Orbit whose skies are blanketed with massive clouds. Most life on the moon is infected with a bacteria called Helioschosis which turns their skin to stone when in contact with sunlight--an adaptation to solar flares that often occur on the moon.
The native population of Nimbus are the Moku, a deeply religious island society who eschew the use of technology because of their belief that Helioschosis was a curse inflicted upon them by their Goddess for hubris. The Moku were briefly occupied by the Homyn Kingdom, but rebelled and declared independence when the Homyn attempted to exterminate their religion.
Nimbus is home to many beautiful tropical environments. The native Ahano fruit that grows there is a delicacy among Homyn and possesses sight-enhancing properties. Powerful and ancient artifacts can be found in the various abandoned Moku settlements that dot the island, including entire villages turned to stone after being caught unaware by a sudden shift in cloud patterns.
The moon does hold several dangers, including a group of pirates known as the Salamanders who inhabit a chain of volcanic islands from which they take their name. A legnedary leviathan named Keli-Ki the Kraken also sits imprisoned deep beneath the moon, using its powerful psychich abilities to influence and enslave a cult of followers who do its bidding.

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