- The baby Tyrannosaurs rampaging among the young mammals quickly became rather distressing, culminating with one baby violently pushing an aardvark so he'll fall right into his sibling's waiting, hungry mouth.
- Later when Sid is forcing the same baby to spit the aardvark out, he ends up spitting out a different mammal. How many other innocent animals did the babies eat?
- The looming threat that Rudy poses for the entirety of Dawn of the Dinosaurs, who makes even Mama cower in terror. When his shadow appears over the cave that Mama, the babies, and Sid are bedding down in, no less than a minute after they've taken shelter there.
- The gas cavern. Sure, it's funny with the gas making Manny, Diego, Crash. Eddie and Buck's voice high-pitched and it makes them laugh silly, but then Buck points to the skeletons of laughing dinosaurs. In other words, the gas is essentially a helium version of the Joker Toxin!
- The fact that Buck got one of his eyes clawed by Rudy in his backstory told to the gang. Does that remind you of anything?
- As the Herd are trekking through the Jungle of Misery, some pitcher plants surround Ellie and watch her with their eyestalks. She understandably starts feeling disturbed.
- Then Manny misinterprets her alarm as hunger and attempts to pick a fruit that's lying around in plain sight...which turns out to be a trap laid by a carnivorous flower that grabs Manny and Diego with its vines and traps them inside its petals. According to Buck, they'll be digested in minutes if they don't get out.
Nightmare Fuel / Ice Age 3: Dawn of the Dinosaurs