How many movies have Yuen Wo-Ping and Yuen Yat-Choh collaborated on?

They have worked on 16 movies together! Their first movie together was The Boxer from Shantung (1972) while their highest rated movie together was The Miracle Fighters (1982). They have not worked together since In the Line of Duty 4 (1989). They are most known for their action films together.