How many movies have Iginio Straffi and Perla Liberatori collaborated on?

They have worked on 3 movies together! Their first movie together was Winx Club: The Secret of the Lost Kingdom (2007) while their highest rated movie together was Winx Club: The Mystery of the Abyss (2014). They have not worked together since Winx Club: The Mystery of the Abyss (2014). They are most known for their animation films together.