Lone Caveman

The Lone Caveman is an Easter Egg located on the Campaign level SIerra 117. Unlike the Caveman Family, the Lone Caveman is outside of the map, and can only be seen through a glitch.

Tutorial
To get to the Lone Caveman Easter Egg, just use the Sierra 117 Vacation to get out of the map, and the Caveman is in the far bushes by the first Hall of Mirrors Effect outside this map.

Other Stuff

 * Just like the Caveman Family, this Caveman can be shot, and can bleed, and has the face of a Marcus Lehto, the character designer. The Lone Caveman lacks animations, so will only bleed no matter what you do to it.
 * The Caveman Family was definitely an Easter Egg, but the Lone Caveman might have been put outside of the level for testing purposes, and they might have forgotten to delete it.