How many movies have Shotaro Ishinomori and Tôru Hirayama collaborated on?

They have worked on 6 movies together! Their first movie together was Inazuman Flash (1974) while their highest rated movie together was Kamen Rider: Eight Riders vs. Galaxy King (1980). They have not worked together since Birth of the 10th! Kamen Riders All Together!! (1984). They are most known for their science fiction films together.