How many movies have Lee Young-jun and Um Sang-hyun collaborated on?

They have worked on 4 movies together! Their first movie together was Miniforce: New Heroes Rise (2016) while their highest rated movie together was Miniforce: Raid of Hamburger Monsters (2020). They have not worked together since Miniforce: Raid of Hamburger Monsters (2020). They are most known for their animation films together.