How many movies have Kris Zimmerman and Robert Alvarez collaborated on?

They have worked on 3 movies together! Their first movie together was Yogi the Easter Bear (1994) while their highest rated movie together was Scooby-Doo on Zombie Island (1998). They have not worked together since Billy & Mandy's Big Boogey Adventure (2007). They are most known for their animation films together.