Megg Achievement in Halo: The Master Chief Collection

This Easter Egg can be found in the mission, The Pillar of Autumn.

The hidden “sign” in this mission is a bloody heart made of bullet holes in the shape of an “M” that can only be discovered under a series of nearly impossible feats. This Egg was created by the original lead designer of the game as a gift for his girlfriend whose name was Meg. Be sure to follow the guidelines listed below in order to reach this hidden Egg.

• Start The Pillar of Autumn on the Legendary difficulty (you must be playing alone)
• After you gain control of the Master Chief, walk toward the canisters behind you
• Crouch jump on top the yellow canister and then jump off
• Move through the level as normal until you get to the bridge of the Autumn
• Trigger the cinematic by walking towards Captain Keyes
• Once he hands you the Magnum, go through the exit and kill the three Grunts
• Head back into the bridge and kill Captain Keyes
• This will trigger a squad of "Invincible Marines" out of the previously locked door that was on the right side of the bridge’s exit
• As Cortana finishes saying, "John-117 has gone rampant," a second door (right behind the first locked door) unlocks
• Wait until the marines crowd one side of the bridge
• Run past them and into the previously locked door

Once you enter this second room, walk through the entire hallway. At the end of the room, look up towards the ceiling and shine your flashlight in Classic Mode. You will see the “M” shot into the ceiling and the achievement will then unlock.