Ilgishin (イルギシン, Irugishin) is a Horror that emerged from an old horror film that is able to send people into illusionary worlds, possessing characteristics of various Horror movie characters. Ilgishin possesses the body of Harima, a Horror film buff projectionist who allows the Horror to enter him so he can enact revenge on his manager for intending to close the movie theater down. Acting on Harima's passion, instead of feeding, Ilgishin places his victims in films to watch them get killed off by the film's monstrous antagonists. When Raiga refuses to play by his rules, Ilgishin personally battles the Makai Knight before being destroyed when Raiga uses his Madō Flame to burn him and his film away.
- Ilgishin plays homage to several American horror movies, from his design incorporating the elements of Freddy Kruger's face and glove, Jason's hockey mask, Leatherface's chainsaw, and Pinhead's skull, to his host's knowledge of movies that include the works of George Romero, World War Z, Scream, and Silence of the Lambs.
- Harima is portrayed by Kitaro (きたろう Kitarō) who played Tamasaburo Kazari (Oyassan) in Kamen Rider Kuuga.