Triceratops

The Triceratops (a.k.a. Trike) is a dinosaur in Warped. Much like the Giant Bear in Cortex Strikes Back, it was a replacement for the traditional Boulders seen in Crash 1 and 2. It is mostly seen in Prehistoric levels, such as Bone Yard. When Crash Bandicoot wanders too far, the Triceratops erupts from its cave [barred up by bones] and chases after you. Obstacles include lava pits, logs and pterosaurs that sometimes rest on these logs. The pterosaurs will fly away, but they may carry Crash away if he gets too close.. It is unknown why the Triceratops chases you, but it's possibly because it believes you trespassed in its territory. When you fall into another 'floor' he stops chasing you. This replaces what a 'gate' or a 'door' blocks him, like the boulder in Crash 1.

Trivia

 * A prehistoric Lab Assistant, as seen in a drawing at the official Naughty Dog website, was originally supposed to be riding the Triceratops, but the idea was later scrapped due to technical reasons. On a side note, the Trike also had an additional nasal horn in the same drawing, which is not seen on the real animal.
 * Trike, Rusty Walrus, and the Giant Bear are all related in the way that they are in chase levels and they are immune to nitro crates and other dangers.