Iris

Iris was Gamera's final foe in the Heisei trilogy, and shares some sort of genetic connection to his arch-enemy Gyaos. A legendary demon referred to as the "Ryuseicho" by residents of Asuka in Nara, Japan, Iris was sealed away long ago inside a small shrine outside of a village. Iris remained inside a stone egg within the shrine for countless generations until it was discovered by a young woman named Ayana Hirasaka, who held an intense hatred of Gamera because she believed he killed her parents. Ayana's hatred caused her to form a bond with Iris, which hatched from its egg and began growing rapidly until it reached the size of Gamera himself. Iris followed Ayana to Kyoto and attempted to kill Gamera for her, then tried to forcibly merge itself with her. Gamera rescued Ayana from the beast, then destroyed Iris by plunging his flaming arm into a wound on its chest.