The Land Before Time IV (1996)

Littlefoot notices a longneck herd entering Great Valley, and informs his grandparents. They tell him that the longnecks are their cousins, and that they must go and greet them. As the Old One, the leader of the herd, tells the residents of the great valley that her herd has been migratory since a heavy rain period turned their old home into a marshland called "The Land of Mists", and became the home of many dangerous creatures, Littlefoot meets a longneck girl named Ali, and invites her to play. He introduces her to his friends, but as she is not used to associating with diverse species, she is afraid of them.

Meanwhile, Grandpa falls ill, and the Old One notes that the illness is lethal unless the victim eats the petals of the "Night Flower", a flower which can only be found in the Land of Mists. Though Littlefoot is warned that the journey is too dangerous, he feels determined to save his grandfather, and asks Ali to take him there. She agrees, on the condition that the other children do not come; they will slow them down. As the two of them make their way, they pass through a cave, and sudden earthshake (earthquake) causes stalagmites and stalactites to crash down, separating them. Ali decides the others will have to help her free Littlefoot, and runs off to get them. Littlefoot, in the meantime, tries to find a way out, and meets an old Archelon named Archie, who offers to help him dig through the rocks. They are interrupted by a (blind) belly dragger (Deinosuchus) and a sharp beak (Ichthyornis) named Dil and Ichy, who have their minds set to eat them....