Pleasant Goat and Big Big Wolf: Movie 04 - Mission Incredible: Adventures on the Dragon's Trail

Sinopsis

It is said that there is a thousands years old treasure that must be found before it fall into the wrong hands, and the Dragon flute which only the real descendant of the dragon can open the door of the treasure. It's a race against time and full onslaught of enemies to stop the heroes from there quest. (Source: AniDB)