How many movies have Eitoku and Seiji Takaiwa collaborated on?

They have worked on 13 movies together! Their first movie together was Kamen Rider Kabuto: God Speed Love (2006) while their highest rated movie together was Kamen Rider Den-O & Kiva: Climax Deka (2008). They have not worked together since Kamen Rider Heisei Generations FINAL: Build & Ex-Aid with Legend Riders (2017). They are most known for their science fiction films together.