|“||What in the animal kingdom was that?!||„|
|~ Sid after outrunning Maelstrom.|
They were first seen in the movie thawing out in a melting pack of ice. Their first victim is Fast Tony's Glyptodon sidekick Stu.
They made one scene in the film when they tried to eat Manny, Sid, Diego, Ellie, Crash, and Eddie when they were crossing a frozen area of water. Cretaceous wanted to eat Manny because he was the biggest animal in the whole herd, while Maelstrom attacks Sid and Diego when they got separated from the others. Despite almost loosing their lives, the heroes managed to escape.
They appear later in the film when Ellie is trapped in a cave from the rising flood. When Manny and his friends went to rescue Ellie, Cretaceous and Maelstrom tried to eat them, starting with Manny who was in the water trying to save Ellie. However, Manny tricks them into hitting a log wedged between a large rock, causing the rock to fall and crush the two vicious reptiles.
- Despite being the main antagonists, their role in the movie is small.
- They both appeared in the Ice Age 2: The Meltdown Wii and DS games as bosses. One of the levels involves Scrat finding a way out of Maelstrom's digestive system.
- A species resembling Cretaceous can be seen in the app game, Ice Age Village called Metri. It is unknown if Maelstrom will be appearing as well.
- In the app game Ice Age Adventure, the player can battle Cretaceous to help Buck get to the other side to meet Granny.
- Cretaceous is the only of the two who can walk on dry land.