The Land Before Time VI: The Secret of Saurus Rock (1998)
Legends claim that Saurus Rock keeps bad luck out of the Great Valley. Is it really true? Could the mysterious Longneck named Doc be the famous Lone Dinosaur, who can defeat a Sharptooth with his lasso-like tail? To find out, Littlefoot and company must cross the great Valley and face a dangerous Sharptooth themselves!