How many movies have Ken Ootsuka and Shinichi Iimura collaborated on?

They have worked on 4 movies together! Their first movie together was The Prince of Tennis: Two Samurais, The First Game (2005) while their highest rated movie together was Fate/stay night: Unlimited Blade Works (2010). They have not worked together since Eureka: Eureka Seven Hi-Evolution (2021). They are most known for their animation films together.