Megg

Summary
Jaime Griesemer, lead designer on Halo: Combat Evolved, gave his then girlfriend Meg (aka Pallor of Subnova) a gift in the form of an easter egg. The egg, affectionally called the Megg, was hidden in Pillar of Autumn (Level) under a series of bizarre triggers (almost impossible feats) to ensure that no one could find it accidentally. The Megg itself is a heart made from human blood, with an M made from bullet holes in the center.

Directions

 * 1) Start the level on Legendary, single player.
 * 2) After you come out of the cryo-tube, turn and jump onto the top of it.
 * 3) Jump onto the shield-charger.
 * 4) Jump onto the walkway.
 * 5) Walk toward the wall with the exit.
 * 6) Walk the other way, to the other side.
 * 7) Jump onto the yellow canister.
 * 8) Wait ten seconds, and then jump back to the walkway.
 * 9) Walk toward the far wall.
 * 10) Step off, and then move through the level as normal until you reach the second battle.
 * 11) Run past the Marine who asks you to follow him.
 * 12) When you get to the bridge, run to the other side without triggering the cinematic and jump down into the small pit.
 * 13) Wait for the message about how to climb ladders to appear, and then climb up and trigger the cinematic.
 * 14) After Keyes gives you his Pistol, go through the exit and kill the three Grunts.
 * 15) Get the Assault Rifle and go back to the bridge.
 * 16) Kill a crewman with a headshot or melee.
 * 17) Run towards the exit.
 * 18) Invincible Marines will pour out of a previously locked door; use the AR to keep them at bay.
 * 19) As Cortana finishes saying "The Master Chief has gone Rampant," a door in the corridor the Marines came from unlocks.
 * 20) Go through the door and enter a hallway. At the end of the hall, you will find the Megg on the ceiling.