Hippo

Hippos are animals that first appeared in Crash Bandicoot 2: Cortex Strikes Back.

Crash Bandicoot 2: Cortex Strikes Back
Hippos appear in Hang Eight, Air Crash, and Plant Food, where they act as platforms. Once Crash lands on them, the hippos will sink into the water for a few moments.

Crash Bandicoot: The Wrath of Cortex
A hippo was originally meant to appear in Crash Bandicoot: The Wrath of Cortex in Jungle Rumble in the stampede of Rhinos that would pursue Crash in that level. Its model is still present in the game, so it can be enabled in Jungle Rumble via hacking.