How many movies have Katsuya Yamamoto and Ryusei Nakao collaborated on?

They have worked on 4 movies together! Their first movie together was Go! Anpanman: The Shining Star's Tear (1989) while their highest rated movie together was Go! Anpanman: Baikinman's Counterattack (1990). They have not worked together since Go! Anpanman: The Flying Picture Book and the Glass Shoes (1996). They are most known for their animation films together.