Chronicles of Kyrvaast
Kyrath (the Emerald Moon)
Kyrath is one of Athalas' three moons. The other two are Sangral the Blood Moon, and Siluen the Silvery Moon. All three moons emit nocturnal light (instead of merely reflecting the light of Thanos) and affect magic on Athalas in strange ways.
Greenborn, children born with green skin, who are supposedly the Chosen of Kyr, are also strangely affected by the phases of Kyrath, and the Emerald Moon is also linked with Greenfire, a magical power which a rare few are born with.