sentences:  It is revealed in "Makai Senki", that Sigma Fudō had stolen Gyanon as he intends to utilize the Horror in powering up his Magōryū Idea while reviving the fiend with large numbers of human sacrifices.To achieve this goal, Sigma obtains the pelt of a Spirit Beast to ensure the revived Gyanon is under his complete control while infusing Kouga's body and soul into the Horror to complete his resurrection.Though Kouga is freed, Gyanon awakens after Idea's creation in response to Sigma's darkness, devouring him and assimilating the ultimate Gōryū while assuming his androgynous human-like form.