Cavemen



There is an Easter Egg on the Halo 3 level, "Sierra 117", you can find a family of four cavemen (or possibly monkeys) with Marcus Lehto's face. They all vary in size, with the largest holding what appears to be a teddy bear, the smallest being half the size of the teddy bear.

Guide
To find the cavemen family (or monkeys/apes as some people call them), go past the point where Sergeant Major Avery Johnson says his Pelican got shot down. Then, enter the jungle and stick to the left wall. You will have to climb over some rocks and then there's a giant rock in the way and you crouch under a tight ledge to find them. You can shoot them but not kill them, although blood will still spurt out, which shows that the respawn cycle is not set up, so they won't die.

Lone Monkey Man
 Recently found, there is a monkey man sitting on a cliff outside the level, in the area where you rescue Sergeant Major Johnson. He is accessible by means of a glitch, but he is still visible by using a scoped weapon, such as a sniper or the binoculars. To get where the Caveman is, you must play in at least two players cooperative play. It is much easier by using a Gravity Hammer, this may be the reason why the chieftain was put there. When you are there, you can keep running and get out of the level.

Trivia

 * When you shoot any caveman, it will bleed, but if you do anything that would normally kill anything (i.e. grenade, getting "headshots"), nothing will happen, no matter how many times you do this, because they have no death animation. Similarly, if you shoot the teddy bear, blood will come out, too.
 * All of the Cavemen are identical, scaled down versions of each other (except for the biggest one, because that one has a teddy bear).
 * If viewed with a sniper, there seems to be a stick figure cave drawing drawn by the cavemen in the dark corner behind them.
 * In Halo 3: ODST, A Caveman is seen next to Edward Buck in the Epilogue cutscene as an easter egg.