Feylen was a member of the Cike who, not long before Rin joined, was immured in the Chuluu Korikh. He channeled a god of wind, and the god began to take over Feylen’s mind and body. Altan breaks Feylen out of the Chuluu Korikh, believing himself able to help Feylen the person dominate the god trapped in his mortal body—but he’s ultimately unsuccessful. The god has fully taken control, and it escapes into Nikan in Feylen’s body.